U.S. patent application number 13/608976 was filed with the patent office on 2013-03-14 for compounds having semiconducting properties and related compositions and devices.
The applicant listed for this patent is Damien Boudinet, Antonio Facchetti, Jordan Quinn, Hakan Usta. Invention is credited to Damien Boudinet, Antonio Facchetti, Jordan Quinn, Hakan Usta.
Application Number | 20130062598 13/608976 |
Document ID | / |
Family ID | 47116279 |
Filed Date | 2013-03-14 |
United States Patent
Application |
20130062598 |
Kind Code |
A1 |
Usta; Hakan ; et
al. |
March 14, 2013 |
Compounds Having Semiconducting Properties and Related Compositions
and Devices
Abstract
Disclosed are new compounds having semiconducting properties.
Such compounds can be processed in solution-phase at a temperature
of less than about 50.degree. C. into thin film semiconductors that
exhibit high carrier mobility and/or good current modulation
characteristics.
Inventors: |
Usta; Hakan; (Evanston,
IL) ; Boudinet; Damien; (Chicago, IL) ; Quinn;
Jordan; (Mundelein, IL) ; Facchetti; Antonio;
(Chicago, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Usta; Hakan
Boudinet; Damien
Quinn; Jordan
Facchetti; Antonio |
Evanston
Chicago
Mundelein
Chicago |
IL
IL
IL
IL |
US
US
US
US |
|
|
Family ID: |
47116279 |
Appl. No.: |
13/608976 |
Filed: |
September 10, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61533785 |
Sep 12, 2011 |
|
|
|
Current U.S.
Class: |
257/40 ;
257/E51.025; 257/E51.026; 549/41; 549/456; 549/457; 570/128;
570/129; 570/183; 585/26 |
Current CPC
Class: |
C07D 495/04 20130101;
H01L 51/052 20130101; H01L 51/0545 20130101; H01L 51/0558 20130101;
C07D 493/04 20130101; H01L 51/0074 20130101; H01L 51/5296 20130101;
H01L 51/0541 20130101; H01L 51/0562 20130101; H01L 51/0525
20130101; H01L 51/0516 20130101 |
Class at
Publication: |
257/40 ; 549/41;
549/456; 549/457; 570/183; 570/129; 570/128; 585/26; 257/E51.025;
257/E51.026 |
International
Class: |
C07D 495/04 20060101
C07D495/04; H01L 51/54 20060101 H01L051/54; C07C 13/62 20060101
C07C013/62; H01L 51/30 20060101 H01L051/30; C07D 493/04 20060101
C07D493/04; C07C 22/04 20060101 C07C022/04 |
Claims
1-24. (canceled)
25. A compound having formula I: ##STR00021## wherein: X is
selected from S, O, and CH.dbd.CH; Y is selected from S, O, and
CH.dbd.CH; Z is H or CHR.sup.1R.sup.1'; R', R.sup.1', R.sup.2, and
R.sup.2' independently are selected from a linear C.sub.1-40 alkyl
group, a linear C.sub.2-40 alkenyl group, and a linear C.sub.1-40
haloalkyl group; and m, at each occurrence, independently is
selected from 0, 1, 2, 3, and 4.
26. The compound of claim 25, wherein the compound has the formula
II: ##STR00022## wherein Z, R.sup.2, R.sup.2', and m are as defined
in claim 25.
27. The compound of claim 25, wherein the compound has the formula
III: ##STR00023## wherein Z, R.sup.2, R.sup.2', and m are as
defined in claim 25.
28. The compound of claim 25, wherein the compound has the formula
IV: ##STR00024## wherein Z, R.sup.2, R.sup.2', and m are as defined
in claim 25.
29. The compound of claim 25, wherein Z is CHR.sup.1R.sup.1', and
each m independently is selected from 1, 2, and 3.
30. The compound of claim 29, wherein R.sup.1 and R.sup.2
independently are selected from a linear C.sub.3-40 alkyl group, a
linear C.sub.3-40 alkenyl group, and a linear C.sub.3-40 haloalkyl
group; and R.sup.1' and R.sup.2' independently are selected from
CH.sub.3, CF.sub.3, C.sub.2H.sub.5, CH.sub.2CF.sub.3,
CF.sub.2CH.sub.3, and C.sub.2F.sub.5.
31. The compound of claim 25, wherein the compound has the formula
IIa, IIIa, or IVa: ##STR00025## wherein R.sup.1 and R.sup.2
independently are selected from C.sub.2H.sub.5, n-C.sub.3H.sub.7,
n-C.sub.4H.sub.9, n-C.sub.5H.sub.11, n-C.sub.6H.sub.13,
n-C.sub.7H.sub.15, n-C.sub.8H.sub.17, n-C.sub.9H.sub.19,
n-C.sub.10H.sub.21, n-C.sub.11H.sub.23, and n-C.sub.12H.sub.25; and
m.sup.1 and m.sup.2 independently are selected from 0, 1, and
2.
32. The compound of claim 25, wherein the compound has the formula
IIb, IIIb, IVb, IIc, IIIc, or IVc: ##STR00026## wherein R.sup.1 and
R.sup.2 independently are selected from C.sub.2H.sub.5,
n-C.sub.3H.sub.7, n-C.sub.4H.sub.9, n-C.sub.5H.sub.11,
n-C.sub.6H.sub.13, n-C.sub.7H.sub.15, n-C.sub.8H.sub.17,
n-C.sub.9H.sub.19, n-C.sub.10H.sub.21, n-C.sub.11H.sub.23, and
n-C.sub.12H.sub.25; and m.sup.1 and m.sup.2 independently are
selected from 0, 1, and 2.
33. The compound of claim 25, wherein the compound has the formula
V, VI, or VII: ##STR00027## wherein R.sup.2 is selected from a
linear C.sub.3-40 alkyl group, a linear C.sub.3-40 alkenyl group,
and a linear C.sub.3-40 haloalkyl group; R.sup.2' is selected from
CH.sub.3, CF.sub.3, C.sub.2H.sub.5, CH.sub.2CF.sub.3,
CF.sub.2CH.sub.3, and C.sub.2F.sub.5; and m.sup.1 and m.sup.2
independently are selected from 0, 1, and 2.
34. The compound of claim 25, wherein the compound has the formula
Va, VIa, VIIa, Vb, VIb, or VIIb: ##STR00028## wherein R.sup.2 is
selected from a linear C.sub.3-40 alkyl group, a linear C.sub.3-40
alkenyl group, and a linear C.sub.3-40 haloalkyl group; R.sup.2' is
selected from CH.sub.3, CF.sub.3, C.sub.2H.sub.5, CH.sub.2CF.sub.3,
CF.sub.2CH.sub.3, and C.sub.2F.sub.5; and m.sup.1 and m.sup.2
independently are selected from 0, 1, and 2.
35. A thin film semiconductor comprising a compound of claim
25.
36. An electronic device, an optical device, or an optoelectronic
device comprising the thin film semiconductor of claim 35.
37. A field effect transistor device comprising a source electrode,
a drain electrode, a gate electrode, and the thin film
semiconductor of claim 35 in contact with a dielectric
material.
38. The field effect transistor device of claim 37, wherein the
field effect transistor has a structure selected from top-gate
bottom-contact structure, bottom-gate top-contact structure,
top-gate top-contact structure, and bottom-gate bottom-contact
structure.
39. The field effect transistor device of claim 37, wherein the
dielectric material comprises an organic dielectric material.
40. The field effect transistor device of claim 37, wherein the
dielectric material comprises an inorganic dielectric material or a
hybrid organic/inorganic dielectric material.
41. A light emitting transistor device comprising a source
electrode, a drain electrode, a gate electrode, a dielectric
material, and a photoactive component comprising a compound of
claim 25, wherein the photoactive component is in contact with the
dielectric material.
42. The light emitting transistor device of claim 41, wherein the
photoactive component comprises a laminate of two or more
layers.
43. The light emitting transistor device of claim 42, wherein the
laminate comprises a light emitting layer and one or more organic
charge transport layers.
44. The light emitting transistor device of claim 41, wherein the
compound of claim 25 is present in a blend material.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and the benefit of U.S.
Provisional Patent Application Ser. No. 61/533,785, filed on Sep.
12, 2011, the disclosure of which is incorporated by reference
herein in its entirety.
BACKGROUND
[0002] Organic optoelectronic devices such as organic thin film
transistors (OTFTs), organic light emitting diodes (OLEDs), organic
light emitting transistors (OLETs), printable circuits, organic
photovoltaic devices, capacitors and sensors are fabricated using
small molecule or polymeric semiconductors as their active
components. To achieve high speed performance and efficient
operation, it is desirable that both the p-type and n-type
semiconductor materials in these organic semiconductor-based
devices exhibit high charge carrier mobility (.mu.) and stability
under ambient conditions, and can be processed in a cost-effective
manner.
[0003] Accordingly, the art continues to desire new organic
semiconductors, particularly those having good stability,
processing properties, and/or charge transport characteristics in
ambient conditions.
SUMMARY
[0004] In light of the foregoing, the present teachings relate to
new semiconducting compounds that can exhibit properties such as
good charge transport characteristics under ambient conditions,
chemical stability, low-temperature processability, large
solubility in common solvents, and processing versatility. As a
result, semiconductor devices such as thin film transistors and
light emitting transistors that incorporate the present compounds
as the semiconductor layer can have high performance under ambient
conditions, for example, demonstrating one or more of large
electron mobilities, low threshold voltages, and high current
on-off ratios.
[0005] In various embodiments, the present teachings provide
compounds of formula I:
##STR00001##
wherein: [0006] X is selected from S, O, and CH.dbd.CH; [0007] Y is
selected from S, O, and CH.dbd.CH; [0008] Z is H or
CHR.sup.1R.sup.1'; [0009] R.sup.1, R.sup.140 , R.sup.2, and
R.sup.2' independently are selected from a linear C.sub.1-40 alkyl
group, a linear C.sub.2-40 alkenyl group, and a linear C.sub.1-40
haloalkyl group; and [0010] m, at each occurrence, independently is
selected from 0, 1, 2, 3, and 4.
[0011] The present teachings also provide methods of preparing
semiconductor materials, as well as various compositions,
composites, and devices that incorporate the compounds and
semiconductor materials disclosed herein.
[0012] The foregoing as well as other features and advantages of
the present teachings will be more fully understood from the
following figures, description, examples, and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] It should be understood that the drawings described below
are for illustration purpose only. The drawings are not necessarily
to scale, with emphasis generally being placed upon illustrating
the principles of the present teachings. The drawings are not
intended to limit the scope of the present teachings in any
way.
[0014] FIG. 1 illustrates four different configurations of thin
film transistors: bottom-gate top contact (a), bottom-gate
bottom-contact (b), top-gate bottom-contact (c), and top-gate
top-contact (d); each of which can be used to incorporate compounds
of the present teachings.
[0015] FIG. 2 shows representative transfer plots of
2,9-1MP-DNTT-based OTFT devices (top-gate bottom-contact) at
different channel lengths (L).
[0016] FIG. 3 shows a representative transfer plot of a
2,9-1MP-DNTT-based OTFT device (bottom-gate bottom-contact, L=10
.mu.m).
DETAILED DESCRIPTION
[0017] Throughout the description, where compositions are described
as having, including, or comprising specific components, or where
processes are described as having, including, or comprising
specific process steps, it is contemplated that compositions of the
present teachings also consist essentially of, or consist of, the
recited components, and that the processes of the present teachings
also consist essentially of, or consist of, the recited process
steps.
[0018] In the application, where an element or component is said to
be included in and/or selected from a list of recited elements or
components, it should be understood that the element or component
can be any one of the recited elements or components, or can be
selected from a group consisting of two or more of the recited
elements or components. Further, it should be understood that
elements and/or features of a composition, an apparatus, or a
method described herein can be combined in a variety of ways
without departing from the spirit and scope of the present
teachings, whether explicit or implicit herein.
[0019] The use of the terms "include," "includes," "including,"
"have," "has," or "having" should be generally understood as
open-ended and non-limiting unless specifically stated
otherwise.
[0020] The use of the singular herein includes the plural (and vice
versa) unless specifically stated otherwise. In addition, where the
use of the term "about" is before a quantitative value, the present
teachings also include the specific quantitative value itself,
unless specifically stated otherwise. As used herein, the term
"about" refers to a .+-.10% variation from the nominal value.
[0021] It should be understood that the order of steps or order for
performing certain actions is immaterial so long as the present
teachings remain operable. Moreover, two or more steps or actions
may be conducted simultaneously.
[0022] As used herein, "halo" or "halogen" refers to fluoro,
chloro, bromo, and iodo.
[0023] As used herein, "alkyl" refers to a straight-chain or
branched saturated hydrocarbon group. Examples of alkyl groups
include methyl (Me), ethyl (Et), propyl (e.g., n-propyl and
iso-propyl), butyl (e.g., n-butyl, iso-butyl, sec-butyl,
tert-butyl), pentyl groups (e.g., n-pentyl, iso-pentyl, neopentyl),
hexyl groups, and the like. In various embodiments, an alkyl group
can have 1 to 40 carbon atoms (i.e., C.sub.1-40 alkyl group), for
example, 1-20 carbon atoms (i.e., C.sub.1-20 alkyl group). In some
embodiments, an alkyl group can have 1 to 6 carbon atoms, and can
be referred to as a "lower alkyl group." Examples of lower alkyl
groups include methyl, ethyl, propyl (e.g., n-propyl and
iso-propyl), and butyl groups (e.g., n-butyl, iso-butyl, sec-butyl,
tert-butyl).
[0024] As used herein, "haloalkyl" refers to an alkyl group having
one or more halogen substituents. At various embodiments, a
haloalkyl group can have 1 to 40 carbon atoms (i.e., C.sub.1-40
haloalkyl group), for example, 1 to 20 carbon atoms (i.e.,
C.sub.1-20 haloalkyl group). Examples of haloalkyl groups include
CF.sub.3, C.sub.2F.sub.5, CHF.sub.2, CH.sub.2F, CCl.sub.3,
CHCl.sub.2, CH.sub.2Cl, C.sub.2Cl.sub.5, and the like. Perhaloalkyl
groups, i.e., alkyl groups where all of the hydrogen atoms are
replaced with halogen atoms (e.g., CF.sub.3 and C.sub.2F.sub.5),
are included within the definition of "haloalkyl." For example, a
C.sub.1-40 haloalkyl group can have the formula
--C.sub.sH.sub.2s+1-tX.sup.0.sub.t, where X.sup.0, at each
occurrence, is F, Cl, Br or I, s is an integer in the range of 1 to
40, and t is an integer in the range of 1 to 81, provided that t is
less than or equal to 2s+1. Haloalkyl groups that are not
perhaloalkyl groups can be substituted as described herein.
[0025] As used herein, "alkenyl" refers to a straight-chain or
branched alkyl group having one or more carbon-carbon double bonds.
Examples of alkenyl groups include ethenyl, propenyl, butenyl,
pentenyl, hexenyl, butadienyl, pentadienyl, hexadienyl groups, and
the like. The one or more carbon-carbon double bonds can be
internal (such as in 2-butene) or terminal (such as in 1-butene).
In various embodiments, an alkenyl group can have 2 to 40 carbon
atoms (i.e., C.sub.2-40 alkenyl group), for example, 2 to 20 carbon
atoms (i.e., C.sub.2-20 alkenyl group).
[0026] At various places in the present specification, substituents
are disclosed in groups or in ranges. It is specifically intended
that the description include each and every individual
subcombination of the members of such groups and ranges. For
example, the term "C.sub.1-6 alkyl" is specifically intended to
individually disclose C.sub.1, C.sub.2, C.sub.3, C.sub.4, C.sub.5,
C.sub.6,
[0027] C.sub.1-C.sub.6, C.sub.1-C.sub.5, C.sub.1-C.sub.4,
C.sub.1-C.sub.3, C.sub.1-C.sub.2, C.sub.2-C.sub.6, C.sub.2-C.sub.5,
C.sub.2-C.sub.4, C.sub.2-C.sub.3, C.sub.3-C.sub.6, C.sub.3-C.sub.5,
C.sub.3-C.sub.4, C.sub.4-C.sub.6, C.sub.4-C.sub.5, and
C.sub.5-C.sub.6 alkyl. By way of other examples, an integer in the
range of 0 to 40 is specifically intended to individually disclose
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
36, 37, 38, 39, and 40, and an integer in the range of 1 to 20 is
specifically intended to individually disclose 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20. Additional
examples include that the phrase "optionally substituted with 1-5
substituents" is specifically intended to individually disclose a
chemical group that can include 0, 1, 2, 3, 4, 5, 0-5, 0-4, 0-3,
0-2, 0-1, 1-5, 1-4, 1-3, 1-2, 2-5, 2-4, 2-3, 3-5, 3-4, and 4-5
substituents.
[0028] Compounds described herein can contain an asymmetric atom
(also referred as a chiral center) and some of the compounds can
contain two or more asymmetric atoms or centers, which can thus
give rise to optical isomers (enantiomers) and diastereomers
(geometric isomers). The present teachings include such optical
isomers and diastereomers, including their respective resolved
enantiomerically or diastereomerically pure isomers (e.g., (+) or
(-) stereoisomer) and their racemic mixtures, as well as other
mixtures of the enantiomers and diastereomers. In some embodiments,
optical isomers can be obtained in enantiomerically enriched or
pure form by standard procedures known to those skilled in the art,
which include, for example, chiral separation, diastereomeric salt
formation, kinetic resolution, and asymmetric synthesis. The
present teachings also encompass cis- and trans-isomers of
compounds containing alkenyl moieties (e.g., alkenes, azo, and
imines). It also should be understood that the compounds of the
present teachings encompass all possible regioisomers in pure form
and mixtures thereof. In some embodiments, the preparation of the
present compounds can include separating such isomers using
standard separation procedures known to those skilled in the art,
for example, by using one or more of column chromatography,
thin-layer chromatography, simulated moving-bed chromatography, and
high-performance liquid chromatography. However, mixtures of
regioisomers can be used similarly to the uses of each individual
regioisomer of the present teachings as described herein and/or
known by a skilled artisan.
[0029] It is specifically contemplated that the depiction of one
stereoisomer includes any other stereoisomer and any stereoisomeric
mixtures unless specifically stated otherwise.
[0030] As used herein, a "p-type semiconductor material" or a
"p-type semiconductor" refers to a semiconductor material having
holes as the majority current carriers. In some embodiments, when a
p-type semiconductor material is deposited on a substrate, it can
provide a hole mobility in excess of about 10.sup.-5 cm.sup.2/Vs.
In the case of field-effect devices, a p-type semiconductor can
also exhibit a current on/off ratio of greater than about 10.
[0031] As used herein, an "n-type semiconductor material" or an
"n-type semiconductor" refers to a semiconductor material having
electrons as the majority current carriers. In some embodiments,
when an n-type semiconductor material is deposited on a substrate,
it can provide an electron mobility in excess of about 10.sup.-5
cm.sup.2/Vs. In the case of field-effect devices, an n-type
semiconductor can also exhibit a current on/off ratio of greater
than about 10.
[0032] As used herein, "mobility" refers to a measure of the
velocity with which charge carriers, for example, holes (or units
of positive charge) in the case of a p-type semiconductor material
and electrons in the case of an n-type semiconductor material, move
through the material under the influence of an electric field. This
parameter, which depends on the device architecture, can be
measured using a field-effect device or space-charge limited
current measurements.
[0033] Throughout the specification, structures may or may not be
presented with chemical names. Where any question arises as to
nomenclature, the structure prevails.
[0034] The present teachings provide various semiconducting small
molecule compounds (small molecule semiconductors) as well as
compositions and organic semiconductor materials prepared from such
compounds and compositions. The organic semiconductor materials
disclosed herein can exhibit useful electrical properties and can
be solution-processable, e.g., spin-coatable and printable. The
semiconductor materials disclosed herein can be used to fabricate
various organic electronic articles, structures and devices,
including field-effect transistors, light emitting transistors,
unipolar circuitries, complementary circuitries, and photovoltaic
devices.
[0035] More specifically, the present teachings relate to compounds
having formula I:
##STR00002##
wherein: [0036] X is selected from S, O, and CH.dbd.CH; [0037] Y is
selected from S, O, and CH.dbd.CH; [0038] Z is H or
CHR.sup.1R.sup.1'; [0039] R.sup.1, R.sup.1', R.sup.2, and R.sup.2'
independently are selected from a linear C.sub.1-40 alkyl group, a
linear C.sub.2-40 alkenyl group, and a linear C.sub.1-40 haloalkyl
group; and [0040] m, at each occurrence, independently is selected
from 0, 1, 2, 3, and 4.
[0041] In some embodiments, the present compounds can be
represented by formula II-IV:
##STR00003##
wherein Z, R.sup.2, R.sup.2', and m are as described herein. In
certain embodiments, Z can be H. In other embodiments, Z can be
CHR.sup.1R.sup.1' , in which case, R.sup.1 can be the same or
different from R.sup.1'. Likewise, in some embodiments, R.sup.2 can
be different from R.sup.2'. For example, R.sup.1' and R.sup.2' can
be selected from a linear C.sub.1-6 alkyl group, a linear C.sub.2-6
alkenyl group, and a linear C.sub.1-6 haloalkyl group; whereas
R.sup.1 and R.sup.2 can be selected from a linear C.sub.3-40 alkyl
group, a linear C.sub.3-40 alkenyl group, and a linear C.sub.3-40
haloalkyl group; preferably selected from a linear C.sub.6-40 alkyl
group, a linear C.sub.6-40 alkenyl group, and a linear C.sub.6-40
haloalkyl group; more preferably selected from a linear C.sub.8-40
alkyl group, a linear C.sub.8-40 alkenyl group, and a linear
C.sub.8-40 haloalkyl group. In particular embodiments, R.sup.1' and
R.sup.2' can be selected from CH.sub.3, CF.sub.3, C.sub.2H.sub.5,
CH.sub.2CF.sub.3, CF.sub.2CH.sub.3, and C.sub.2F.sub.5; whereas
R.sup.1 and R.sup.2 can be selected from a linear C.sub.3-20 alkyl
group, a linear C.sub.3-20 alkenyl group, and a linear C.sub.3-20
haloalkyl group.
[0042] In certain embodiments, the present compounds can be
represented by formula IIa, IIIa, or IVa:
##STR00004##
wherein R.sup.1 and R.sup.2 independently are selected from
C.sub.2H.sub.5, n-C.sub.3H.sub.7, n-C.sub.4H.sub.9,
n-C.sub.5H.sub.11, n-C.sub.6H.sub.13, n-C.sub.7H.sub.15,
n-C.sub.8H.sub.17, n-C.sub.9H.sub.19, n-C.sub.10H.sub.21,
n-C.sub.11H.sub.23, and n-C.sub.12H.sub.25; and m.sup.1 and m.sup.2
independently are selected from 0, 1, and 2. In particular
embodiments, the present compounds can be optically pure
stereoisomers. For example, certain compounds of formula II-IV can
be stereospecific and can be represented by formula IIb, IIIb, IVb,
IIc, IIIc, or IVc:
##STR00005##
wherein R.sup.1 and R.sup.2 independently are selected from
C.sub.2H.sub.5, n-C.sub.3H.sub.7, n-C.sub.4H.sub.9,
n-C.sub.5H.sub.11, n-C.sub.6H.sub.13, n-C.sub.7H.sub.15,
n-C.sub.8H.sub.17, n-C.sub.9H.sub.19, n-C.sub.10H.sub.21,
n-C.sub.11H.sub.23, and n-C.sub.12H.sub.25; and m.sup.1 and m.sup.2
independently are selected from 0, 1, and 2.
[0043] In some embodiments, the present compounds can be
represented by formula V, VI, or VII:
##STR00006##
wherein R.sup.2 is selected from a linear C.sub.3-40 alkyl group, a
linear C.sub.3-40 alkenyl group, and a linear C.sub.3-40 haloalkyl
group; R.sup.2' is selected from CH.sub.3, CF.sub.3,
C.sub.2H.sub.5, CH.sub.2CF.sub.3, CF.sub.2CH.sub.3, and
C.sub.2F.sub.5; and m.sup.1 and m.sup.2 independently are selected
from 0, 1, and 2. In particular embodiments, the present compounds
can be optically pure stereoisomers. For example, certain compounds
of formula V-VII can be stereospecific and can be represented by
formula Va, VIa, oVIIa, Vb, VIb, or VIIb:
##STR00007##
wherein R.sup.2 is selected from a linear C.sub.3-40 alkyl group, a
linear C.sub.3-40 alkenyl group, and a linear C.sub.3-40 haloalkyl
group; R.sup.2' is selected from CH.sub.3, CF.sub.3,
C.sub.2H.sub.5, CH.sub.2CF.sub.3, CF.sub.2CH.sub.3, and
C.sub.2F.sub.5; and m.sup.1 and m.sup.2 independently are selected
from 0, 1, and 2.
[0044] In various embodiments of compounds of formula I, each m can
be the same or different. For example, certain embodiments of the
present compounds can be represented by formula:
##STR00008##
[0045] wherein R.sup.1 and R.sup.2 independently are selected from
a linear C.sub.3-40 alkyl group, a linear C.sub.3-40 alkenyl group,
and a linear C.sub.3-40 haloalkyl group.
[0046] In certain embodiments of compounds of formula I, X and Y
can be different. For example, certain compounds of formula I can
be represented by formula:
##STR00009##
wherein R.sup.1 and R.sup.2 independently are selected from a
linear C.sub.3-40 alkyl group, a linear C.sub.3-40 alkenyl group,
and a linear C.sub.3-40 haloalkyl group.
[0047] To further illustrate, certain compounds of formula I can be
represented by formula:
##STR00010## ##STR00011## ##STR00012##
wherein R.sup.2 is selected from a linear C.sub.3-40 alkyl group, a
linear C.sub.3-40 alkenyl group, and a linear C.sub.3-40 haloalkyl
group.
[0048] Compounds of the present teachings can be prepared according
to procedures described in Examples 1-5. Alternatively, the present
compounds can be prepared from commercially available starting
materials, compounds known in the literature, or via other readily
prepared intermediates, by employing standard synthetic methods and
procedures known to those skilled in the art. Standard synthetic
methods and procedures for the preparation of organic molecules and
functional group transformations and manipulations can be readily
obtained from the relevant scientific literature or from standard
textbooks in the field. It will be appreciated that where typical
or preferred process conditions (i.e., reaction temperatures,
times, mole ratios of reactants, solvents, pressures, etc.) are
given, other process conditions can also be used unless otherwise
stated. Optimum reaction conditions can vary with the particular
reactants or solvent used, but such conditions can be determined by
one skilled in the art by routine optimization procedures. Those
skilled in the art of organic synthesis will recognize that the
nature and order of the synthetic steps presented can be varied for
the purpose of optimizing the formation of the polymers described
herein.
[0049] The processes described herein can be monitored according to
any suitable method known in the art. For example, product
formation can be monitored by spectroscopic means, such as nuclear
magnetic resonance spectroscopy (NMR, e.g., .sup.1H or .sup.13C),
infrared spectroscopy (IR), spectrophotometry (e.g., UV-visible),
mass spectrometry (MS), or by chromatography such as high pressure
liquid chromatography (HPLC), gas chromatography (GC),
gel-permeation chromatography (GPC), or thin layer chromatography
(TLC).
[0050] The reactions or the processes described herein can be
carried out in suitable solvents which can be readily selected by
one skilled in the art of organic synthesis. Suitable solvents
typically are substantially nonreactive with the reactants,
intermediates, and/or products at the temperatures at which the
reactions are carried out, i.e., temperatures that can range from
the solvent's freezing temperature to the solvent's boiling
temperature. A given reaction can be carried out in one solvent or
a mixture of more than one solvent. Depending on the particular
reaction step, suitable solvents for a particular reaction step can
be selected.
[0051] Various compounds according to the present teachings can
have good charge transport properties and can be stable under
ambient conditions ("ambient stable"), soluble in common solvents,
and in turn solution-processable into various articles, structures,
or devices. In particular, compared to other compounds that may
have a conjugated core similar to the present compounds, the
substituent(s) CHR.sup.1R.sup.1' and/or CHR.sup.2R.sup.2' was found
to confer greatly improved processability, specifically, in
solution-phase at or near room temperature. For example, while
prior art compounds may require hot solution processing (e.g.,
temperature at about 100.degree. C.) with aggressive (e.g.,
chlorinated) solvents, the present compounds can be processed at a
temperature less than about 50.degree. C. using non-halogenated
(e.g., non-chlorinated solvents).
[0052] Accordingly, the present teachings provide organic
semiconductor devices that include one or more compounds described
herein as semiconductors. Examples of such organic semiconductor
devices include various electronic devices, optical devices, and
optoelectronic devices such as thin film transistors (e.g., field
effect transistors), photovoltaics, photodetectors, organic light
emitting devices such as organic light emitting diodes (OLEDs) and
organic light emitting transistors (OLETs), complementary metal
oxide semiconductors (CMOSs), complementary inverters, diodes,
capacitors, sensors, D flip-flops, rectifiers, ring oscillators,
integrated circuits (ICs), radiofrequency identification (RFID)
tags, electroluminescent displays, and organic memory devices. In
some embodiments, the present teachings provide for a thin film
semiconductor including one or more compounds described herein and
a field effect transistor device including the thin film
semiconductor. In particular, the field effect transistor device
has a structure selected from top-gate bottom-contact structure,
bottom-gate top-contact structure, top-gate top-contact structure,
and bottom-gate bottom-contact structure. In certain embodiments,
the field effect transistor device includes a dielectric material,
wherein the dielectric material includes an organic dielectric
material, an inorganic dielectric material, or a hybrid
organic/inorganic dielectric material. In other embodiments, the
present teachings provide for photovoltaic devices and organic
light emitting devices incorporating a thin film semiconductor that
includes one or more compounds described herein.
[0053] As described above, compounds of the present teachings
generally have good solubility in a variety of common solvents.
Thus, various embodiments of the present compounds can be processed
via inexpensive solution-phase techniques into electronic devices,
optical devices, or optoelectronic devices. As used herein, a
compound can be considered soluble in a solvent when at least 1 mg
of the compound can be dissolved in 1 mL of the solvent. Examples
of common non-chlorinated organic solvents include petroleum
ethers; acetonitrile; aromatic hydrocarbons such as benzene,
toluene, xylene, and mesitylene; ketones such as acetone and methyl
ethyl ketone; ethers such as tetrahydrofuran, dioxane,
bis(2-methoxyethyl) ether, diethyl ether, di-isopropyl ether, and
t-butyl methyl ether; alcohols such as methanol, ethanol, butanol,
and isopropyl alcohol; aliphatic hydrocarbons such as hexanes;
acetates such as methyl acetate, ethyl acetate, methyl formate,
ethyl formate, isopropyl acetate, and butyl acetate; amides such as
dimethylformamide and dimethylacetamide; sulfoxides such as
dimethylsulfoxide; and cyclic solvents such as cyclopentanone,
cyclohexanone, and 2-methypyrrolidone.
[0054] Accordingly, the present teachings further provide
compositions that include one or more compounds disclosed herein
dissolved or dispersed in a fluid medium, for example, an organic
solvent. In some embodiments, the composition can further include
one or more additives independently selected from detergents,
dispersants, binding agents, compatiblizing agents, curing agents,
initiators, humectants, antifoaming agents, wetting agents, pH
modifiers, biocides, and bactereriostats. For example, surfactants
and/or other polymers (e.g., polystyrene, polyethylene,
poly-alpha-methylstyrene, polyisobutene, polypropylene,
polymethylmethacrylate, and the like) can be included as a
dispersant, a binding agent, a compatiblizing agent, and/or an
antifoaming agent.
[0055] Various deposition techniques, including various
solution-processing techniques, have been used with organic
electronics. For example, much of the printed electronics
technology has focused on inkjet printing, primarily because this
technique offers greater control over feature position and
multilayer registration. Inkjet printing is a noncontact process,
which offers the benefits of not requiring a preformed master
(compared to contact printing techniques), as well as digital
control of ink ejection, thereby providing drop-on-demand printing.
However, contact printing techniques have the key advantage of
being well-suited for very fast roll-to-roll processing. Exemplary
contact printing techniques include screen-printing, gravure,
offset, flexo, and microcontact printing. Other solution processing
techniques include, for example, spin coating, drop-casting, zone
casting, dip coating, and blade coating.
[0056] The present compounds can exhibit versatility in their
processing. Formulations including the present compounds can be
printable via different types of printing techniques including
gravure printing, flexographic printing, and inkjet printing,
providing smooth and uniform films that allow, for example, the
formation of a pinhole-free dielectric film thereon, and
consequently, the fabrication of all-printed devices.
[0057] The present teachings, therefore, further provide methods of
preparing a semiconductor material. The methods can include
preparing a composition that includes one or more compounds
disclosed herein dissolved or dispersed in a fluid medium such as a
solvent or a mixture of solvents, depositing the composition on a
substrate to provide a semiconductor material precursor, and
processing (e.g., heating) the semiconductor precursor to provide a
semiconductor material (e.g., a thin film semiconductor) that
includes one or more compounds disclosed herein. In some
embodiments, the depositing step can be carried out by printing,
including inkjet printing and various contact printing techniques
(e.g., screen-printing, gravure printing, offset printing, pad
printing, lithographic printing, flexographic printing, and
microcontact printing). In other embodiments, the depositing step
can be carried out by spin coating, drop-casting, zone casting, dip
coating, blade coating, or spraying. In various embodiments, the
depositing step can be carried out at low temperatures, for
example, a temperature less than about 50.degree. C., less than
about 40.degree. C., or about room temperature. More expensive
processes such as vapor deposition also can be used.
[0058] The present teachings further provide articles of
manufacture, for example, composites that include a thin film
semiconductor of the present teachings and a substrate component
and/or a dielectric component. The substrate component can be
selected from doped silicon, an indium tin oxide (ITO), ITO-coated
glass, ITO-coated polyimide or other plastics, aluminum or other
metals alone or coated on a polymer or other substrate, a doped
polythiophene, and the like. The dielectric component can be
prepared from inorganic dielectric materials such as various oxides
(e.g., SiO.sub.2, Al.sub.2O.sub.3, HfO.sub.2), organic dielectric
materials such as various polymeric materials (e.g., polycarbonate,
polyester, polystyrene, polyhaloethylene, polyacrylate),
self-assembled superlattice/self-assembled nanodielectric
(SAS/SAND) materials (e.g., as described in Yoon, M-H. et al.,
PNAS, 102 (13): 4678-4682 (2005), the entire disclosure of which is
incorporated by reference herein), as well as hybrid
organic/inorganic dielectric materials (e.g., as described in U.S.
Pat. No. 7,678,463, the entire disclosure of which is incorporated
by reference herein). In some embodiments, the dielectric component
can include the crosslinked polymer blends described in U.S. Pat.
No. 7,605,394, the entire disclosure of which is incorporated by
reference herein. The composite also can include one or more
electrical contacts. Suitable materials for the source, drain, and
gate electrodes include metals (e.g., Au, Al, Ni, Cu), transparent
conducting oxides (e.g., ITO, IZO, ZITO, GZO, GIO, GITO), and
conducting polymers (e.g., poly(3,4-ethylenedioxythiophene)
poly(styrenesulfonate) (PEDOT:PSS), polyaniline (PANI), polypyrrole
(PPy)). One or more of the composites described herein can be
embodied within various organic electronic, optical, and
optoelectronic devices such as organic thin film transistors
(OTFTs), specifically, organic field effect transistors (OFETs), as
well as sensors, capacitors, unipolar circuits, complementary
circuits (e.g., inverter circuits), and the like.
[0059] Accordingly, an aspect of the present teachings relates to
methods of fabricating an organic field effect transistor that
incorporates a semiconductor material of the present teachings. The
semiconductor materials of the present teachings can be used to
fabricate various types of organic field effect transistors
including top-gate top-contact structures, top-gate bottom-contact
structures, bottom-gate top-contact structures, and bottom-gate
bottom-contact structures.
[0060] FIG. 1 illustrates the four common types of OFET structures:
(a) bottom-gate top-contact structure, (b) bottom-gate
bottom-contact structure, (c) top-gate bottom-contact structure,
and (d) top-gate top-contact structure. As shown, in each of the
configurations, the semiconductor component is in contact with the
source and drain electrodes, and the gate dielectric component is
in contact with the semiconductor component on one side and the
gate electrode on an opposite side.
[0061] In certain embodiments, OTFT devices can be fabricated with
one or more compounds disclosed herein on doped silicon substrates,
using SiO.sub.2 as the dielectric, in top-contact geometries. In
particular embodiments, the active semiconductor layer which
incorporates one or more compounds disclosed herein can be
deposited at room temperature or at an elevated temperature. In
other embodiments, the active semiconductor layer which
incorporates one or more compounds disclosed herein can be applied
by spin-coating or printing as described herein. For top-contact
devices, metallic contacts can be patterned on top of the films
using shadow masks.
[0062] In certain embodiments, OTFT devices can be fabricated with
one or more compounds disclosed herein on plastic foils, using
polymers as the dielectric, in top-gate bottom-contact geometries.
In particular embodiments, the active semiconducting layer which
incorporates one or more compounds disclosed herein can be
deposited at room temperature or at an elevated temperature. In
other embodiments, the active semiconducting layer which
incorporates one or more compounds disclosed herein can be applied
by spin-coating or printing as described herein. Gate and
source/drain contacts can be made of Au, other metals, or
conducting polymers and deposited by vapor-deposition and/or
printing.
[0063] In various embodiments, a semiconducting component
incorporating one or more compounds disclosed herein can exhibit
p-type semiconducting activity, for example, a hole mobility of
10.sup.-4 cm.sup.2/V-sec or greater and/or a current on/off ratio
(I.sub.on/I.sub.off) of 10.sup.3 or greater.
[0064] Other articles of manufacture in which one or more compounds
disclosed herein can be useful include photovoltaics or solar
cells. The present compounds can exhibit broad optical absorption
and/or a tuned redox properties and bulk carrier mobilities.
Accordingly, the present compounds can be used, for example, as a
p-type semiconductor in a photovoltaic design, which includes an
adjcaent n-type semiconductor to form a p-n junction. The present
compounds can be in the form of a thin film semiconductor, or a
composite including the thin film semiconductor deposited on a
substrate.
[0065] The present teachings further provide light emitting
transistors including a source electrode, a drain electrode, a gate
electrode, a dielectric material and a photoactive component
comprising one or more compounds disclosed herein. In some
embodiments, the compound(s) disclosed herein can be present in a
blend material. In some embodiments, the photoactive component can
be a laminate of two more layers, for example, including a light
emitting layer and one or more organic charge transport layers. In
particular embodiments, the present compound(s) can be present in
one of the organic charge transport layers, particularly a hole
transport layer.
[0066] The following examples are provided to illustrate further
and to facilitate the understanding of the present teachings and
are not in any way intended to limit the invention.
[0067] Unless otherwise noted, all reagents were purchased from
commercial sources and used without further purification. Some
reagents were synthesized according to known procedures Anhydrous
tetrahydrofuran (THF) was distilled from sodium/benzophenone.
Reactions were carried out under nitrogen unless otherwise noted.
UV-Vis spectra were recorded on a Cary Model 1 UV-vis
spectrophotometer. NMR spectra were recorded on a Varian Unity Plus
500 spectrometer (.sup.1H, 500 MHz; .sup.13C, 125 MHz).
Electrospray mass spectrometry was performed on a Thermo Finnegan
model LCQ Advantage mass spectrometer.
EXAMPLE 1
Synthesis of 2,9-1MP-DNTT
##STR00013## ##STR00014##
[0069] 2-methoxy-6-(1-hydroxy-1-methylpentyl)naphthalene (1):
n-BuLi (2.5 M in hexanes, 6.2 mL, 15.5 mmol) was added dropwise to
a solution of 2-methoxy-6-bromonaphthalene (3.5 g, 14.76 mmol) in
THF (120 mL) at -78.degree. C. under nitrogen. After stirring at
-78.degree. C. for 2 h, 2-hexanone (2.19 mL, 17.71 mmol) was added
dropwise, and the solution was warmed to room temperature and
stirred overnight. The reaction mixture was quenched with water and
the organic layer was separated. Next, the organic phase was washed
with water, dried over Na.sub.2SO.sub.4, and concentrated on a
rotary evaporator to give a semi-solid crude compound. The crude
was purified by column chromatography (silica gel,
hexane:dichloromethane (1:4, v/v)) to give 1 as a white solid (3.0
g, 79% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.: 7.84 (d,
1H, J=1.5 Hz), 7.74 (d, 1H, J=8.5 Hz), 7.72 (d, 1H, J=8.5 Hz), 7.50
(dd, 1H, J=8.5 Hz, 1.5 Hz), 7.14 (m, 2H), 3.93 (s, 3H), 1.90 (m,
2H), 1.64 (s, 3H), 1.13-1.28 (m, 4H), 0.84 (t, 3H).
[0070] 2-methoxy-6-(1-methylpentyl)naphthalene (2): To a solution
of 2-methoxy-6-(1-hydroxy-1-methylpentyl)naphthalene (1, 0.50 g,
1.935 mmol) in dichloromethane (15 mL) was added triethylsilane
(0.35 mL, 2.19 mmol), and the solution was cooled to 0.degree. C.
under nitrogen. Then, the solution was treated with trifluoroacetic
acid (1.49 mL, 19.34 mmol) dropwise over 30 min. The solution was
warmed to room temperature and stirred for 3 h. The reaction
mixture was carefully quenched with NaOH (1M, 25 mL) to give a
basic mixture (pH .about.10), which was extracted with
dichloromethane (100 mL). The organic phase was washed with water,
dried over Na.sub.2SO.sub.4, concentrated on a rotary evaporator to
give the crude compound as an oil. The crude product was purified
by column chromatography (silica gel, hexane:dichloromethane (2:1,
v/v)) to give 2 as a colorless oil (0.34 g, 73% yield). .sup.1H NMR
(CDCl.sub.3 500 MHz): .delta.: 7.70 (d, 1H, J=3.0 Hz), 7.68 (m,
1H), 7.54 (d, 1H, J=2.0 Hz), 7.31 (dd, 1H, 8.5 Hz, 2.0 Hz), 7.12
(m, 2H), 3.92 (s, 3H), 2.82 (m, 1H), 1.65 (m, 2H), 1.31 (d, 3H,
J=7.0 Hz), 1.10-1.28 (m, 4H), 0.83 (t, 3H).
[0071] 2-methoxy-3-methylthio-6-(1-methylpentyl)naphthalene (3): To
a solution of 2-methoxy-6-(1-methylpentyl)naphthalene (2, 1.37 g,
5.65 mmol) in THF (25 mL) was added dropwise n-butyllithium (2.5 M
in hexanes, 2.49 mL, 6.22 mmol) at -78.degree. C. under nitrogen.
The solution was stirred at -78.degree. C. for 15 min and at room
temperature for another 1 h. The solution was then cooled to
-78.degree. C., and dimethyldisulfide (0.61 mL, 6.88 mmol) was
added dropwise. The solution was warmed to room temperature and
stirred for 15 h. The reaction mixture was quenched with saturated
aqueous ammonium chloride solution (50 mL) and extracted with
diethyl ether (200 mL). The organic phase was washed with brine,
dried over Na.sub.2SO.sub.4, concentrated on a rotary evaporator to
give the crude compound as a colorless oil. The crude product was
purified by column chromatography (silica gel,
hexane:dichloromethane (2:1, v/v)) to give 3 as a colorless oil
(1.20 g, 74% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.:
7.64 (d, 1H, J=8.0 Hz), 7.49 (s, 1H), 7.43 (s, 1H), 7.25 (m, 1H),
7.07 (s, 1H), 4.00 (s, 3H), 2.80 (m, 1H), 2.55 (s, 3H), 1.63 (m,
2H), 1.31 (d, 3H, J=7.0 Hz), 1.15-1.23 (m, 4H), 0.84 (t, 3H).
[0072] 6-(1-methylpentyl)-3-methylthio-2-naphthol (4): A solution
of BBr.sub.3 in dichloromethane (1.0 M, 3.55 mL, 3.55 mmol) was
added dropwise to a solution of
2-methoxy-3-methylthio-6-(1-methylpentyl)naphthalene (3, 0.50 g,
1.73 mmol) in dichloromethane (5 mL) at -78.degree. C. under
nitrogen. The solution was then warmed to room temperature and
stirred for 19 h. The reaction mixture was next poured into ice and
the product was extracted with dichloromethane (50 mL). The organic
phase was washed with brine, dried over Na.sub.2SO.sub.4,
concentrated on a rotary evaporator to give 4 as a colorless oil,
which was substantially pure and used for the next step without any
further purification (0.44 g, 93% yield). .sup.1H NMR (CDCl.sub.3
500 MHz): .delta.: 7.97 (s, 1H), 7.63 (d, J=8.5 Hz, 1H), 7.49 (brs,
1H), 7.31 (dd, J=8.5 Hz, 2.0 Hz, 1H), 7.30 (s, 1H), 6.59 (s, 1H),
2.81 (m, 1H), 2.43 (s, 3H), 1.65 (m, 2H), 1.31 (d, 3H, J=7.0 Hz),
1.16-1.29 (m, 4H), 0.85 (t, 3H).
[0073] 6-(1-methylpentyl)-3-methylthio-2-naphtyl
trifluoromethanesulfonate (5): To a solution of
6-(1-methylpentyl)-3-methylthio-2-naphthol (4, 0.86 g, 3.13 mmol)
and pyridine (0.81 mL, 10.02 mmol) in dichloromethane (20 mL) was
added trifluoromethanesulfonic anhydride (0.61 mL, 3.63 mmol) at
0.degree. C. under nitrogen. The reaction mixture was stirred at
room temperature for 16 h, and then diluted with water (10 mL) and
HCl (4M HCl, 10 mL). The organic phase was separated, washed with
brine, dried over Na.sub.2SO.sub.4, concentrated on a rotary
evaporator to give a crude oil product. The crude product was
purified by column chromatography (silica gel,
hexane:dichloromethane (9:1, v/v)) to give 5 as a colorless oil
(1.10 g, 87% yield). .sup.1H NMR (CDC1.sub.3 500 MHz): .delta.:
7.75 (d, 1H, J=8.5 Hz), 7.70 (s, 1H), 7.66 (s, 1H), 7.58 (br s,
1H), 7.38 (dd, 1H, J=8.5 Hz, 1.5 hHz), 2.85 (m, 1H), 2.60 (s, 3H),
1.67 (m, 2H), 1.32 (d, 3H, J=7.0 Hz), 1.15-1.28 (m, 4H), 0.85 (t,
3H).
[0074]
trans-1,2-bis(6-(1-methylpentyl)-3-methylthionaphthalen-2-yl)ethene
(6): The reagents 6-(1-methylpentyl)-3-methylthio-2-naphtyl
trifluoromethanesulfonate (5, 0.60 g, 1.48 mmol),
trans-1,2-bis(tributylstannyl)ethene (0.45 g, 0.74 mmol), and
Pd(PPh.sub.3).sub.4 (25.6 mg, 0.022 mmol) were dissolved in dry DMF
(20 mL) under nitrogen, and the reaction mixture was heated at
100.degree. C. for 15 hours in dark. After cooling to room
temperature, the reaction mixture was diluted with water and
extracted with chloroform (100 mL). The organic phase was washed
with brine, dried over Na.sub.2SO.sub.4, and concentrated on a
rotary evaporator to give a semi-solid crude product. The crude
product was purified by column chromatography (silica gel,
hexane:dichloromethane (4:1, v/v)) to give 6 as a white solid (0.36
g, 82% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.: 8.07 (s,
2H), 7.79 (d, 2H, J=8.5 Hz), 7.65 (s, 2H), 7.62 (s, 2H), 7.53 (s,
2H), 7.30 (dd, 2H, J=8.5 Hz, 1.5 Hz), 2.84 (m, 2H), 2.60 (s, 6H),
1.68 (m, 4H), 1.33 (d, 6H, J=7.0 Hz), 1.17-1.31 (m, 8H), 0.86 (t,
6H).
[0075]
2,9-Bis(1-methylpentyl)dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophe-
ne (2,9-1MP-DNTT): A mixture of
trans-1,2-bis(6-(1-methylpentyl)-3-methylthionaphthalen-2-yl)ethene
(6, 0.80 g, 1.48 mmol) and iodine (12.01 g, 47.32 mmol) in
chloroform (60 mL) was refluxed for 19 h. After cooling to room
temperature, the reaction mixture was quenched with saturated
aqueous sodium hydrogen sulfite solution (100 mL). The organic
phase was separated, washed with brine, dried over
Na.sub.2SO.sub.4, and concentrated on a rotary evaporator to yield
a yellow crude solid. The crude was purified by column
chromatography (silica gel, hexane:dichloromethane (4:1, v/v))
followed by recrystallization from hexane to yield 2,9-1MP-DNTT as
a yellow crystalline solid (0.31 g, 41% yield). .sup.1H NMR
(CDCl.sub.3 500 MHz): .delta.: 8.36 (s, 2H), 8.32 (s, 2H), 7.97 (d,
2H, J=8.5 Hz), 7.70 (s, 2H), 7.41 (d, 2H, J=8.5 Hz), 2.90 (m, 2H),
1.70 (m, 4H), 1.36 (d, 6H, J=7.0 Hz), 1.12-1.34 (m, 8H), 0.89 (t,
6H). .sup.13C NMR (CDCl.sub.3): .delta.14.12, 22.30, 22.85, 30.05,
37.98, 40.21, 119.75, 121.94, 124.38, 125.87, 128.26, 130.07,
131.67, 131.80, 133.36, 140.77, 145.56 ppm. Anal. calcd. for
(C.sub.34H.sub.36S.sub.2): C, 80.26; H, 7.13. Found: C, 80.33; H,
6.91. m.p. 262-263.degree. C.
EXAMPLE 2
Synthesis of 2,9-1MB-DNTT
##STR00015## ##STR00016##
[0077] 2-methoxy-6-(1-hydroxy-1-methylbutyl)naphthalene (1): n-BuLi
(2.5 M in hexanes, 9.2 mL, 22.9 mmol) was added dropwise to a
solution of 2-methoxy-6-bromonaphthalene (5.2 g, 21.85 mmol) in THF
(100 mL) at -78.degree. C. under nitrogen. After stirring at
-78.degree. C. for 1 h, 2-pentanone (2.79 mL, 26.22 mmol) was added
dropwise, and the solution was warmed to room temperature and
stirred overnight. The reaction mixture was quenched with water and
the organic layer was separated. Next, the organic phase was washed
with water, dried over Na.sub.2SO.sub.4, and concentrated on a
rotary evaporator to give a semi-solid crude compound, which was
used in the next step without any further purification (5.20 g, 97%
yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.: 7.83 (d, 1H,
J=1.5 Hz), 7.75 (d, 1H, J=8.5 Hz), 7.72 (d, 1H, J=8.5 Hz), 7.52
(dd, 1H, J=8.5 Hz, 1.5 Hz), 7.12 (m, 2H), 3.93 (s, 3H), 1.91 (m,
2H), 1.64 (s, 3H), 1.14-1.29 (m, 2H), 0.83 (t, 3H).
[0078] 2-methoxy-6-(1-methylbutyl)naphthalene (2): To a solution of
2-methoxy-6-(1-hydroxy-1-methylbutyl)naphthalene (1, 5.34 g, 21.86
mmol) in dichloromethane (120 mL) was added triethylsilane (3.90
mL, 24.70 mmol), and the solution was cooled to 0.degree. C. under
nitrogen. Then, the solution was treated with trifluoroacetic acid
(16.84 mL, 218.6 mmol) dropwise over 30 min. The solution was
warmed to room temperature and stirred overnight. The reaction
mixture was carefully quenched with NaOH (1M, 25 mL) to give a
basic mixture (pH .about.10), which was extracted with
dichloromethane (100 mL). The organic phase was washed with water,
dried over Na.sub.2SO.sub.4, concentrated on a rotary evaporator to
give the crude compound as an oil. The crude product was purified
by column chromatography (silica gel, hexane:dichloromethane (2:1,
v/v)) to give 2 as a colorless oil (3.20 g, 64% yield). .sup.1H NMR
(CDCl.sub.3 500 MHz): .delta.: 7.71 (d, 1H, J=3.0 Hz), 7.69 (m,
1H), 7.54 (d, 1H, J=2.0 Hz), 7.34 (dd, 1H, 8.5 Hz, 2.0 Hz), 7.14
(m, 2H), 3.93 (s, 3H), 2.83 (m, 1H), 1.63 (m, 2H), 1.31 (d, 3H,
J=7.0 Hz), 1.11-1.29 (m, 2H), 0.82 (t, 3H).
[0079] 2-methoxy-3-methylthio-6-(1-methylbutyl)naphthalene (3): To
a solution of 2-methoxy-6-(1-methylbutyl)naphthalene (2, 3.00 g,
13.14 mmol) in THF (60 mL) was added dropwise n-butyllithium (2.5 M
in hexanes, 5.78 mL, 14.45 mmol) at -78.degree. C. under nitrogen.
The solution was stirred at -78.degree. C. for 15 min and at room
temperature for another 1 h. The solution was then cooled to
-78.degree. C., and dimethyldisulfide (1.40 mL, 15.77 mmol) was
added dropwise. The solution was warmed to room temperature and
stirred overnight. The reaction mixture was quenched with saturated
aqueous ammonium chloride solution (50 mL) and extracted with
diethyl ether (200 mL). The organic phase was washed with brine,
dried over Na.sub.2SO.sub.4, concentrated on a rotary evaporator to
give the crude compound as a colorless oil. The crude product was
purified by column chromatography (silica gel,
hexane:dichloromethane (3:1, v/v)) to give 3 as a colorless oil
(2.60 g, 72% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.:
7.63 (d, 1H, J=8.0 Hz), 7.52 (s, 1H), 7.44 (s, 1H), 7.24 (m, 1H),
7.08 (s, 1H), 4.01 (s, 3H), 2.83 (m, 1H), 2.54 (s, 3H), 1.63 (m,
2H), 1.31 (d, 3H, J=7.0 Hz), 1.16-1.24 (m, 2H), 0.83 (t, 3H).
[0080] 6-(1-methylbutyl)-3-methylthio-2-naphthol (4): A solution of
BBr.sub.3 in dichloromethane (1.0 M, 18.67 mL, 18.67 mmol) was
added dropwise to a solution of
2-methoxy-3-methylthio-6-(1-methylpentyl)naphthalene (3, 2.50 g,
9.11 mmol) in dichloromethane (25 mL) at -78.degree. C. under
nitrogen. The solution was then warmed to room temperature and
stirred for 20 h. The reaction mixture was next poured into ice and
the product was extracted with dichloromethane (50 mL). The organic
phase was washed with brine, dried over Na.sub.2SO.sub.4,
concentrated on a rotary evaporator to give 4 as a colorless oil,
which was substantially pure and used for the next step without any
further purification (2.35 g, 99% yield). .sup.1H NMR (CDCl.sub.3
500 MHz): .delta.: 7.98 (s, 1H), 7.64 (d, J=8.5 Hz, 1H), 7.49 (brs,
1H), 7.33 (dd, J=8.5 Hz, 2.0 Hz, 1H), 7.31 (s, 1H), 6.60 (s, 1H),
2.82 (m, 1H), 2.45 (s, 3H), 1.64 (m, 2H), 1.32 (d, 3H, J=7.0 Hz),
1.17-1.30 (m, 2H), 0.83 (t, 3H).
[0081] 6-(1-methylbutyl)-3-methylthio-2-naphtyl
trifluoromethanesulfonate (5): To a solution of
6-(1-methylbutyl)-3-methylthio-2-naphthol (4, 2.0 g, 7.68 mmol) and
pyridine (1.99 mL, 24.58 mmol) in dichloromethane (50 mL) was added
trifluoromethanesulfonic anhydride (1.48 mL, 8.83 mmol) at
0.degree. C. under nitrogen. The reaction mixture was stirred at
room temperature for 16 h, and then diluted with water (10 mL) and
HCl (4M HCl, 10 mL). The organic phase was separated, washed with
brine, dried over Na.sub.2SO.sub.4, concentrated on a rotary
evaporator to give a crude oil product. The crude product was
purified by column chromatography (silica gel,
hexane:dichloromethane (8:1, v/v)) to give 5 as a colorless oil
(2.40 g, 80% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.:
7.74 (d, 1H, J=8.5 Hz), 7.71 (s, 1H), 7.67 (s, 1H), 7.60 (br s,
1H), 7.39 (dd, 1H, J=8.5 Hz, 1.5 hHz), 2.83 (m, 1H), 2.59 (s, 3H),
1.68 (m, 2H), 1.32 (d, 3H, J=7.0 Hz), 1.15-1.28 (m, 2H), 0.83 (t,
3H).
[0082]
trans-1,2-bis(6-(1-methylbutyl)-3-methylthionaphthalen-2-yl)ethene
(6): The reagents 6-(1-methylbutyl)-3-methylthio-2-naphtyl
trifluoromethanesulfonate (5, 1.50 g, 3.82 mmol),
trans-1,2-bis(tributylstannyl)ethene (1.16 g, 1.91 mmol), and
Pd(PPh.sub.3).sub.4 (66.2 mg, 0.057 mmol) were dissolved in dry DMF
(50 mL) under nitrogen, and the reaction mixture was heated at
100.degree. C. for 18 hours in dark. After cooling to room
temperature, the reaction mixture was diluted with water and
extracted with chloroform (100 mL). The organic phase was washed
with brine, dried over Na.sub.2SO.sub.4, and concentrated on a
rotary evaporator to give a semi-solid crude product. The crude
product was purified by column chromatography (silica gel,
hexane:dichloromethane (4:1, v/v)) to give 6 as a white solid (0.83
g, 85% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.: 8.10 (s,
2H), 7.80 (d, 2H, J=8.5 Hz), 7.67 (s, 2H), 7.63 (s, 2H), 7.54 (s,
2H), 7.31 (dd, 2H, J=8.5 Hz, 1.5 Hz), 2.83 (m, 2H), 2.61 (s, 6H),
1.69 (m, 4H), 1.34 (d, 6H, J=7.0 Hz), 1.18-1.32 (m, 4H), 0.85 (t,
6H).
[0083]
2,9-Bis(1-methylbutyl)dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophen-
e (2,9-1MB-DNTT): A mixture of
trans-1,2-bis(6-(1-methylbutyl)-3-methylthionaphthalen-2-yl)ethene
(6, 0.60 g, 1.17 mmol) and iodine (9.5 g, 37.44 mmol) in chloroform
(40 mL) was refluxed for 19 h. After cooling to room temperature,
the reaction mixture was quenched with saturated aqueous sodium
hydrogen sulfite solution (100 mL). The organic phase was
separated, washed with brine, dried over Na.sub.2SO.sub.4, and
concentrated on a rotary evaporator to yield a yellow crude solid.
The crude was purified by column chromatography (silica gel,
hexane:chloroform (4:1, v/v)) followed by recrystallization from
hexane to yield 2,9-1MB-DNTT as a yellow crystalline solid (0.31 g,
40% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.: 8.35 (s,
2H), 8.32 (s, 2H), 7.97 (d, 2H, J=8.5 Hz), 7.70 (s, 2H), 7.41 (d,
2H, J=8.5 Hz), 2.93 (m, 2H), 1.74 (m, 4H), 1.37 (d, 6H, J=7.0 Hz),
1.13-1.35 (m, 4H), 0.91 (t, 6H). .sup.13C NMR (CDCl.sub.3): .delta.
14.23, 20.93, 22.25, 39.94, 40.50, 119.75, 121.93, 124.38, 125.87,
128.26, 130.06, 131.66, 131.79, 133.36, 140.78, 145.51 ppm. Anal.
calcd. for (C.sub.32H.sub.32S.sub.2): C, 79.95; H, 6.71. Found: C,
80.03; H, 6.77. m.p. 280-281.degree. C.
EXAMPLE 3
Synthesis of 2,9-1MD-DNTT
##STR00017##
[0085] In this example, 2,9-1MD-DNTT (Example X) has longer alkyl
substitutent (R=--CH(CH.sub.3)C.sub.11H.sub.23) compared to those
of Examples 1 (2,9-1MP-DNTT, R=--CH(CH.sub.3)C.sub.4H.sub.9) and 2
(2,9-1MB-DNTT, R=--CH(CH.sub.3)C.sub.3H.sub.7). Longer alkyl chains
are expected to enhance molecular ordering in thin-film phase via
alkyl chain interdigitations, which may result in highly
crystalline, continuous and uniform film morphologies with enhanced
charge transport characteristics. Additionally, longer alkyl chain
also ensures good solubility of the semiconductor in common organic
solvents for efficient solution-processing. The effect of alkyl
chain length on charge transporting characteristics of non-soluble
DNTT semiconductors was demonstrated in Adv. Mater. 2011, 23,
1222-1225, and .about.5-10-fold mobility enhancement was observed
going from -n-C.sub.6H.sub.13 to -n-C.sub.12H.sub.13 for
vapor-deposited OTFTs.
EXAMPLE 4
Synthesis of 2-1MP-DNTT
##STR00018##
[0087] 2-methoxy-3-methylthionaphthalene (1): To a solution of
2-methoxynaphthalene (5.00 g, 31.60 mmol) in THF (30 mL) was added
dropwise n-butyllithium (2.5 M in hexanes, 13.91 mL, 34.77 mmol) at
-78.degree. C. under nitrogen. The solution was stirred at
-78.degree. C. for 15 min and at room temperature for another 1 h.
The solution was then cooled to -78.degree. C., and
dimethyldisulfide (3.36 mL, 37.88 mmol) was added dropwise. The
solution was warmed to room temperature and stirred for 15 h. The
reaction mixture was quenched with saturated aqueous ammonium
chloride solution (50 mL) and extracted with diethyl ether (200
mL). The organic phase was washed with brine, dried over
Na.sub.2SO.sub.4, concentrated on a rotary evaporator to give the
crude compound as a white solid. The crude product was purified by
recrystallization from Hexanes to give 1 as a white solid (4.64 g,
71% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.: 7.71 (d, 2H,
J=9.0 Hz), 7.42 (s, 1H), 7.38 (m, 2H), 7.10 (s, 1H), 4.02 (s, 3H),
2.56 (s, 3H).
[0088] 3-methylthio-2-naphthol (2): A solution of BBr.sub.3 in
dichloromethane (1.0 M, 37.10 mL, 37.10 mmol) was added dropwise to
a solution of 2-methoxy-3-methylthionaphthalene (1, 3.70 g, 18.11
mmol) in dichloromethane (10 mL) at -78.degree. C. under nitrogen.
The solution was then warmed to room temperature and stirred for 16
h. The reaction mixture was next poured into ice and the product
was extracted with dichloromethane (50 mL). The organic phase was
washed with brine, dried over Na.sub.2SO.sub.4, concentrated on a
rotary evaporator to give 2 as a white solid, which was practically
pure and used for the next step without any further purification
(2.70 g, 78% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.:
7.98 (s, 1H), 7.72 (m, 1H), 7.65 (m, 1H), 7.41 (m, 1H), 7.33 (s,
1H), 7.30 (m, 1H), 6.62 (s, 1H), 2.42 (s, 3H).
[0089] 3-methylthio-2-naphtyl trifluoromethanesulfonate (3): To a
solution of 3-methylthio-2-naphthol (2, 3.0 g, 15.77 mmol) and
pyridine (4.08 mL, 50.45 mmol) in dichloromethane (40 mL) was added
trifluoromethanesulfonic anhydride (3.05 mL, 18.16 mmol) at
0.degree. C. under nitrogen. The reaction mixture was stirred at
room temperature for 18 h, and then diluted with water (30 mL) and
HCl (4M HCl, 30 mL). The organic phase was separated, washed with
brine, dried over Na.sub.2SO.sub.4, concentrated on a rotary
evaporator to give a crude oil product. The crude product was
purified by column chromatography (Silica gel,
Hexane:Dichloromethane (5:1, v/v)) to give 3 as a white solid (3.50
g, 69% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.: 7.81 (m,
2H), 7.74 (s, 1H), 7.70 (s, 1H), 7.54 (m, 2H), 2.61 (s, 3H).
[0090]
trans-1-(6-(1-methylpentyl)-3-methylthionaphthalen-2-yl)-2-(3-methy-
lthionaphthalen-2-yl)ethene (4): The reagents
3-methylthio-2-naphtyl trifluoromethanesulfonate (3, 0.265 g,
0.825mmol), 6-(1-methylpentyl)-3-methylthio-2-naphtyl
trifluoromethanesulfonate (0.335 g, 0.825mmol),
trans-1,2-bis(tributylstannyl)ethene (0.500 g, 0.825 mmol), and
Pd(PPh.sub.3).sub.4 (28.6 mg, 0.025 mmol) were dissolved in dry DMF
(20 mL) under nitrogen, and the reaction mixture was heated at
100.degree. C. for 18 hours in dark. After cooling to room
temperature, the reaction mixture was diluted with water and
extracted with chloroform (200 mL). The organic phase was washed
with brine, dried over Na.sub.2SO.sub.4, and concentrated on a
rotary evaporator to give a semi-solid crude product. The crude
product was purified by column chromatography (Silica gel,
Hexane:Dichloromethane (2:1, v/v)) to give 4 as a yellow semisolid
(0.14 g, 37% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.:
8.11 (s, 1H), 8.07 (s, 1H), 7.78 (d, 1H, J=7.0 Hz), 7.79 (d, 1H,
J=8.5 Hz), 7.77 (d, 1H, J=7.5 Hz), 7.66 (m, 3H), 7.62 (s, 1H), 7.53
(s, 1H), 7.45 (m, 2H), 7.31 (dd, 1H, J=8.5 Hz, 1.5 Hz), 2.85 (m,
1H), 2.61 (s, 3H), 2.60 (s, 3H), 1.67 (m, 2H), 1.33 (d, 3H, J=7.0
Hz), 1.17-1.31 (m, 4H), 0.87 (t, 3H).
[0091]
2-(1-methylpentyl)dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene
(2-1MP-DNTT): A mixture of
trans-1-(6-(1-methylpentyl)-3-methylthionaphthalen-2-yl)-2-(3-methylthion-
aphthalen-2-yl)ethene (4, 0.130 g, 0.285 mmol) and iodine (2.31 g,
9.11 mmol) in chloroform (10 mL) was refluxed for 23 h. After
cooling to room temperature, the reaction mixture was quenched with
saturated aqueous sodium hydrogen sulfite solution (30 mL). The
organic phase was separated, washed with brine, dried over
Na.sub.2SO.sub.4, and concentrated on a rotary evaporator to yield
a yellow crude solid. The crude was purified by passing through a
short plug of silica gel (chloroform as the eluent) followed by a
recrystallization from chloroform to yield 2-1MP-DNTT as a yellow
solid (20 mg, 16.5% yield). .sup.1H NMR (CDCl.sub.3 500 MHz):
.delta.: 8.43 (s, 1H), 8.37 (s, 2H), 8.34 (s, 1H), 8.05 (m, 1H),
7.97 (m, 2H), 7.70 (s, 1H), 7.54 (m, 2H), 7.42 (dd, 1H, J=8.5 Hz,
1.5 Hz), 2.91 (m, 1H), 1.71 (m, 2H), 1.37 (d, 3H, J=7.0 Hz),
1.11-1.35 (m, 4H), 0.87 (t, 3H). m.p.>300.degree. C.
EXAMPLE 5
Synthesis of 1MP-NTTB
##STR00019##
[0093] 2-(methylthio)phenyl trifluoromethanesulfonate (1): To a
solution of 2-(methylthio)phenol (5.0 g, 35.6 mmol) and pyridine
(9.22 mL, 114.1 mmol) in dichloromethane (40 mL) was added
trifluoromethanesulfonic anhydride (6.88 mL, 41.0 mmol) at
0.degree. C. under nitrogen. The reaction mixture was stirred at
room temperature for 18 h, and then diluted with water (40 mL) and
HCl (4M HCl, 40 mL). The organic phase was separated, washed with
brine, dried over Na.sub.2SO.sub.4, concentrated on a rotary
evaporator to give a crude oil product. The crude product was
purified by column chromatography (Silica gel,
Hexane:Dichloromethane (4:1, v/v)) to give 1 as a colorless oil
(9.40 g, 96% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.:
7.36 (dd, 2H, J=4.5 Hz, 1.5 Hz), 7.25 (m, 2H), 2.51 (s, 3H).
[0094] trans-
1-(6-(1-methylpentyl)-3-methylthionaphthalen-2-yl)-2-(2-(methylthio)pheny-
l)ethene (2): The reagents 2-(methylthio)phenyl
trifluoromethanesulfonate (1, 1.00 g, 3.69 mmol),
6-(1-methylpentyl)-3-methylthio-2-naphtyl trifluoromethanesulfonate
(1.50 g, 3.69 mmol), trans-1,2-bis(tributylstannyl)ethene (2.24 g,
3.69 mmol), and Pd(PPh.sub.3).sub.4 (128 mg, 0.11 mmol) were
dissolved in dry DMF (90 mL) under nitrogen, and the reaction
mixture was heated at 100.degree. C. for 14 hours in dark. After
cooling to room temperature, the reaction mixture was diluted with
water and extracted with chloroform (300 mL). The organic phase was
washed with brine, dried over Na.sub.2SO.sub.4, and concentrated on
a rotary evaporator to give a semi-solid crude product. The crude
product was purified by column chromatography (Silica gel,
Hexane:Dichloromethane (5:1, v/v)) to give 2 as a yellow semisolid
(0.365 g, 24% yield). .sup.1H NMR (CDCl.sub.3 500 MHz): .delta.:
8.03 (s, 1H), 7.77 (d, 1H, J=8.0 Hz), 7.69 (dd, 1H, J=8.0 Hz, 1.5
Hz), 7.60 (s, 1H), 7.58 (s, 1H), 7.57 (s, 1H), 7.52 (s, 1H), 7.31
(m, 4H), 2.82 (m, 1H), 2.58 (s, 3H), 2.50 (s, 3H), 1.66 (m, 2H),
1.33 (d, 3H, J=7.0 Hz), 1.17-1.31 (m, 4H), 0.85 (t, 3H).
[0095]
2-(1-methylpentyl)naphtho[2,3-b]benzo[1,2-f]thieno[3,2-b]thiophene
(1MP-NTTB): A mixture of
trans-1-(6-(1-methylpentyl)-3-methylthionaphthalen-2-yl)-2-(2-(methylthio-
)phenyl)ethane (2, 0.365 g, 0.90 mmol) and iodine (7.29 g, 28.72
mmol) in chloroform (30 mL) was refluxed for 16 h. After cooling to
room temperature, the reaction mixture was quenched with saturated
aqueous sodium hydrogen sulfite solution (60 mL). The organic phase
was separated, washed with brine, dried over Na.sub.2SO.sub.4, and
concentrated on a rotary evaporator to yield a yellow crude solid.
The crude was purified by passing through a short plug of silica
gel (chloroform as the eluent) followed by a recrystallization from
chloroform to yield 1MP-NTTB as a yellow solid (120 mg, 36% yield).
.sup.1H NMR (CDCl.sub.3 500 MHz): .delta.: 8.34 (s, 1H), 8.33 (s,
1H), 7.97 (m, 2H), 7.89 (d, 1H, J=8.0 Hz), 7.69 (s, 1H), 7.50 (m,
1H), 7.44 (m, 2H), 2.90 (m, 1H), 1.70 (m, 2H), 1.36 (d, 3H, J=7.0
Hz), 1.12-1.37 (m, 4H), 0.85 (t, 3H). MS (MALDI) m/z (M.sup.+.):
calc. for (C.sub.24H.sub.22S.sub.2), 374.56; found, 373.86. Anal.
calcd. for (C.sub.24H.sub.22S.sub.2): C, 76.96; H, 5.92. Found: C,
76.88; H, 5.90. m.p.>210-211.degree. C.
EXAMPLE 6
Solubility Data Comparison Between 2,9-C.sub.n-DNTT (n=6, 8, 10,
12) and 2,9-1MP-DNTT
[0096] The solubility of C.sub.n-DNTTs (C.sub.n=a linear alkyl
chain) are very low in organic solvents (up to .about.80 mg/L in
toluene at 60.degree. C.) (see: Adv. Mater. 2011, 23, 1222-1225).
The solubility of 2,9-1MP-DNTT can be about 50 g/L in toluene at
60.degree. C., which is >500 times higher than those of the
corresponding linear alkyl chain DNTT compounds having the same (or
lower) number of carbon atoms.
EXAMPLE 7
Device Fabrication and Test Procedures
[0097] Device Fabrication Procedure (Bottom Gate Top Contact
(BGTC)): BGTC TFTs were fabricated using compounds of the present
teachings as the semiconductor layer. N-doped silicon wafers (100)
with 3000 .ANG. thermally grown silicon dioxide layer (Addison
Inc.) were used as device substrates. Prior to deposition of the
semiconductor, the Si/SiO.sub.2 surfaces were modified through a
special octadecyltrichlorosilane (OTS) treatment process. Thin
films of semiconductors approximately 0-120 nm in thickness were
prepared through physical vapor deposition (PVD), with the
deposition rate of 0.1-0.5 .ANG./s and the substrate temperature of
30-120.degree. C. The TFTs were completed by vapor deposition of
300 .ANG. gold source/drain electrodes onto the semiconductor layer
through a stencil mask to define the transistor channel. The
channel lengths and widths are about 50-200 .mu.m and about
500-2000 .mu.m, respectively. The silicon dioxide layer served as
the gate insulator. The gate electrode was accessed through an
ohmic contact to the doped silicon.
[0098] Device Fabrication Procedure (Top Gate Bottom Contact
(TGBC)): For TGBC devices, PolyEthyleneNaphthalate (PEN) substrates
(2''.times.2'') were planarized with UV-curable polymeric films
(ActivInk D1400, Polyera Corp., Skokie, Ill.). A silver layer of 30
nm was then deposited by thermal evaporation. Source and drain
contacts were patterned using photolithography process and silver
was etched by a mixture of acids and water. The semiconductor was
spun from a hydrocarbon solution (15 mg-mL) at 2000 rpm. The
semiconductor film thickness depends on the solubility of the
semiconductor. In the case of 2,9-1MP-DNTT, the film had a
thickness of about 60 nm. These films were then baked on a hot
plate at 110.degree. C. for 10 min to remove residual solvent. The
amorphous fluoropolymer CYTOP (CTL-809M, Asahi Glass Corporation)
was spun as the top-gate dielectric at 5000 rpm to a thickness of
about 450 nm, and baked on a hot plate at about 110.degree. C. for
10 minutes. The device structure was completed by the evaporation
of an aligned Ag top-gate stripe.
[0099] Device Fabrication Procedure (Bottom Gate Bottom Contact
(BGBC)): For BGBC devices, a Cr/Au gate stripe was evaporated on
clean PEN substrates. Subsequently, UV-curable polymeric films
(Activink D1450, Polyera Corp., Skokie, Ill.) were spun (thickness
.about.500 nm) and cured to form the bottom-gate dielectric. A
silver layer of 30 nm was then deposited by thermal evaporation.
Source and drain contacts were patterned using photolithography
process and silver was etched by a mixture of acids and water. Thin
films of the semiconductor were prepared according to the same
protocols as for the TGBC devices.
EXAMPLE 8
Transistor Performance Comparison
[0100] The TFT performance of 2,9-1MP-DNTT were compared vis-a-vis
to that of C8-DNTT (synthesized according to the procedure reported
in Org. Lett. 2011, 13, 3430) in several device architectures. The
results are summarized in Table 1.
TABLE-US-00001 TABLE 1 Summary of average hole mobilities
(.mu..sub.mean), on/off ratios (I.sub.ON/I.sub.OFF), and threshold
voltages (V.sub.T) for various OTFTs. ##STR00020## Semiconductor
Device Deposition Channel .mu..sub.mean V.sub.T Compound
Architecture Method.sup.a Length (.mu.m) (cm.sup.2/V s) (V)
I.sub.ON/I.sub.OFF 2,9-1MP-DNTT BGTC PVD 50-200 .sup.b 1-3 ~-0
~10.sup.6 TGBC SC 20 .sup.c 1.50 0 8 .times. 10.sup.6 TGBC SC 10
.sup.c 1.01 +2 2 .times. 10.sup.6 TGBC SC 5 .sup.c 0.56 +5 1
.times. 10.sup.7 TGBC SC 3 .sup.c 0.35 +6 2 .times. 10.sup.7 BGBC
SC 10 .sup.c 0.70 0 7 .times. 10.sup.6 2,9-1MB-DNTT TGBC SC 10
.sup.c 1.80 +4 1 .times. 10.sup.7 C8-DNTT BGTC PVD 50-200 .sup.b
1-3 ~-5 ~10.sup.6 (comparison) TGBC SC 20 .sup.c inactive -- --
BGBC SC 10 .sup.c inactive -- -- 2-1MP-DNTT BGTC PVD 100 .sup.b 2.3
~-60 ~10.sup.6 2-1MP-NTTB BGTC PVD 100 .sup.b 0.3 ~-25 ~10.sup.6
TGBC SC 10 .sup.c 0.14 ~-2 ~10.sup.7 BGBC SC 10 .sup.c 0.10 ~-2
~10.sup.6 .sup.aSC means spin-coating from a solution of the
compound that was maintained at or near room temperature
(<40.degree. C). .sup.b Electrical contacts are Au. .sup.c
Electrical contacts are Ag.
[0101] FIG. 2 shows representative transfer plots of
2,9-1MP-DNTT-based OTFT devices (top-gate bottom-contact) at
different channel lengths (L). FIG. 3 shows a representative
transfer plot of a 2,9-1MP-DNTT-based OTFT device (bottom-gate
bottom-contact, L=10 .mu.m).
[0102] All devices were characterized in a Signatone Probe Station
using a Keithley 4200 Semiconductor Characterization System to
obtain transfer and output characteristics. Device parameters were
extracted from the transfer characteristics according to standard
transistor equations.
[0103] The present teachings encompass embodiments in other
specific forms without departing from the spirit or essential
characteristics thereof. The foregoing embodiments are therefore to
be considered in all respects illustrative rather than limiting on
the present teachings described herein. Scope of the present
invention is thus indicated by the appended claims rather than by
the foregoing description, and all changes that come within the
meaning and range of equivalency of the claims are intended to be
embraced therein.
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