U.S. patent application number 12/613198 was filed with the patent office on 2010-05-06 for rhodium complexes and iridium complexes.
This patent application is currently assigned to Merck Patent GmbH. Invention is credited to Ingrid Bach, Heinrich Becker, Hubert Spreitzer, Philipp Stossel.
Application Number | 20100113779 12/613198 |
Document ID | / |
Family ID | 28458589 |
Filed Date | 2010-05-06 |
United States Patent
Application |
20100113779 |
Kind Code |
A1 |
Stossel; Philipp ; et
al. |
May 6, 2010 |
RHODIUM COMPLEXES AND IRIDIUM COMPLEXES
Abstract
The present invention describes novel organometallic compounds
which are phosphorescence emitters. Such compounds can, as active
constituents (=functional materials), be used in a number of
different applications, which in the broadest sense can be classed
as belonging to the electronics industry. The compounds according
to the invention are described by the formulas (I), (Ia), (II),
(IIa), (III), (IIIa), (IV) and (IVa).
Inventors: |
Stossel; Philipp; (Frankfurt
Am Main, DE) ; Bach; Ingrid; (Hofheim, DE) ;
Spreitzer; Hubert; (Viernheim, DE) ; Becker;
Heinrich; (Hofheim, DE) |
Correspondence
Address: |
CONNOLLY BOVE LODGE & HUTZ, LLP
P O BOX 2207
WILMINGTON
DE
19899
US
|
Assignee: |
Merck Patent GmbH
Darmstadt
DE
|
Family ID: |
28458589 |
Appl. No.: |
12/613198 |
Filed: |
November 5, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10509920 |
May 25, 2005 |
7635526 |
|
|
PCT/EP03/03023 |
Mar 24, 2003 |
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12613198 |
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Current U.S.
Class: |
544/181 ;
544/225; 546/10; 546/2 |
Current CPC
Class: |
H01L 51/0085 20130101;
C07F 15/0033 20130101; Y02P 70/521 20151101; Y02P 70/50 20151101;
Y02E 10/549 20130101; Y10S 428/917 20130101; C07F 15/0073 20130101;
H01L 51/5012 20130101 |
Class at
Publication: |
544/181 ; 546/2;
546/10; 544/225 |
International
Class: |
C07F 15/00 20060101
C07F015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 5, 2002 |
DE |
DE 102 15 010.9 |
Claims
1. Compounds of the formula (I) and (II), ##STR00022## whereby the
symbols and indices have the following meanings: M Rh, Ir; Z is
identical or different with each occurrence of N, CR; Y O, S, Se; R
is identical or different with each occurrence of H, F, Cl,
NO.sub.2, CN, a straight-chain or branched or cyclical alkyl or
alkoxy group with 1 to 20 C atoms, whereby one or more
non-neighbouring CH.sub.2 groups can be replaced by --O--, --S--,
--NR.sup.1--, or --CONR.sup.2-- and whereby one or more H atoms can
be replaced by F, or an aryl or heteroaryl group with 4 to 14 C
atoms, which can be substituted by one or more non-aromatic
radicals R; whereby several substituents R, both on the same ring
as well as on the two different rings together, can in turn set up
a further mono- or poly-cyclical ring system; R.sup.1,R.sup.2 are
identical or different, H or an aliphatic or aromatic hydrocarbon
radical with 1 to 20 C atoms; n is 1, 2 or 3
2. Compounds of the formula (Ia) and (IIa) ##STR00023## whereby the
symbols and indices have the meanings as in claim 1.
3. Compounds of the formula (III) and (IV), ##STR00024## whereby
the symbols M, Y, R, R.sup.1, R.sup.2 and indices n have the
meanings as in claim 1 and a is 0, 1, 2, 3 or 4, preferably 0, 1 or
2, particularly preferably 0 or 1; b is 0, 1, 2 or 3, preferably 0
or 1.
4. Compounds of the formula (IIIa) and (IVa) ##STR00025## whereby
the symbols and indices have the meanings as in claim 1 and 3.
5. The method for the production of the compounds according to
claim 1, by conversion of the compounds (V) and (VI), ##STR00026##
wherein X is Cl, Br or I and wherein M and the radicals and indices
Z, Y and R have the meanings stated in claim 1, with cyanisation
agents.
6. The method for the production of compounds according to claim 3,
by conversion of the compounds (VII) and (VIII), ##STR00027##
wherein X is Cl, Br or I and wherein M and the radicals and indices
Y, R, a, and b have the meanings stated in claims 1 and 3, with
cyanisation agents.
7. The method according to claim 5 and/or 6, characterised in that,
as cyanisation agents, use is made of systems with cyanide sources
which contain the cyanide ion in ionic or coordinatively bound
form.
8. The method according to one or more of claims 5 to 7,
characterised in that copper(I)cyanide or nickel(II)cyanide are
used as cyanisation agents.
9. The method according to one or more of claims 5 to 8,
characterised in that, as the cyanisation agent, use is made of
zinc(II)cyanide in the presence of zinc and in the presence of
nickel or palladium or a nickel or palladium compound and
optionally a phosphorus-containing additive.
10. The method according to one or more of claims 5 to 9,
characterised in that the molar ratio of cyanisation agents (1) and
(2) to compounds (V), (VI), (VII) and (VIII) amounts to 1n:1 to
10n:1, preferably 1.5n:1 to 3n:1.
11. The method according to one more of claims 5, 6, 9 and 10,
characterised in that the molar ratio of zinc(II)cyanide zu zinc in
cyanisation agents (2) amounts to 1:0.1 to 1:0.001, preferably
1:0.05 to 1:0.005.
12. The method according to one or more of claims 5, 6 and 9 to 11,
characterised in that the ratio of nickel, a nickel compound,
palladium or a palladium compound to compounds (V), (VI), (VII) and
(VIII) amounts to 0.1n:1 to 0.00001n:1.
13. The method according to one or more of claims 5, 6 and 9 to 12,
characterised in that the ratio of the phosphorus-containing
additive to nickel, a nickel compound, palladium or a palladium
compound amounts to 0.5:1 to 1000:1.
14. An electronic component containing at least one compound
according to one or more of claims 1 to 4.
15. The electronic component according to claim 14, characterised
in that it concerns organic light diodes (OLEDs), organic
integrated circuits (O-ICs), organic field-effect transistors
(OFETs), organic thin-film transistors (OTFTs), organic solar cells
(O-SCs) or also organic laser diodes (O-lasers).
Description
[0001] Organometallic compounds--especially compounds of the
d.sup.8-Metals--will, as active components (=functional materials),
find use in the near future as functional components in a number of
different applications, which in the broadest sense can be classed
as belonging to the electronics industry.
[0002] Organic electroluminescence devices based on organic
components (see U.S. Pat. No. 4,539,507 and U.S. Pat. No. 5,151,629
for general description of the structure) and their individual
components, organic light-emitting diodes (OLEDs), have already
been introduced onto the market, as is demonstrated by the
available car radios with "organic display" from the firm Pioneer.
Further such products will shortly be introduced. All the same,
considerable improvements are still required here in order to turn
these displays into a genuine competitor to the currently
market-dominant liquid crystal displays (LCD) and to surpass the
latter.
[0003] A development in this regard, which has been emerging over
the past two years, is the use of organometallic complexes which
exhibit phosphorescence instead of fluorescence [M. A. Baldo, S.
Lamansky, P. E. Burrows, M. E. Thompson, S. R. Forrest, Applied
Physics Letters, 1999, 75, 4-6].
[0004] For theoretical spin-statistical reasons, an up to fourfold
energy and power efficiency is made possible by using
organometallic compounds as phosphorescence emitters. Whether this
new development will become established depends very much on
whether suitable device compositions can be found that are also
capable of putting these advantages to effect (triplet
emission=phosphorescence compared with singlet
emission=fluorescence) in OLEDs. As essential conditions for
practical application, particular mention may be made here of long
operational life, high stability against temperature load and a low
duty and operating voltage in order to enable mobile
applications.
[0005] In addition, there must be efficient chemical access to the
corresponding organometallic compounds. Organo-rhodium and -iridium
compounds are of particular interest. In the case of the latter, it
is of decisive importance that efficient access is enabled to
corresponding derivatives, especially in view of the price of
rhodium and iridium.
[0006] Two types of design of OLEDs that have phosphorescence
emitters as chromophore components have hitherto been described in
the literature.
[0007] The first type (type 1) typically has the following layer
structure [M. E. Thompson et. al., Proceedings of SPIE, 31.07--Feb.
8, 2000, San Diego, USA, Volume 4105, page 119-124]:
Carrier plate=substrate (usually glass or plastic films).
Transparent anode (usually indium tin oxide, ITO). Hole transport
layer: usually based on triarylamine derivates. Electron transport
and emission layer: this layer consists of an electron transport
material which is doped with the phosphorescence emitter. Electron
transport layer: usually based on
aluminium-tris-8-hydroxy-chinoxalinate (AlQ.sub.3). Cathode: as a
rule, use is made here of metals, metal combinations or metal
alloys with a low exit function, such as for example Al--Li.
[0008] The second type (type 2) typically has the following layer
structure [T. Tsutsui et al. Jpn. J. Appl. Phys., 1999, 38, L
1502-L 1504]:
1. Carrier plate=substrate (usually glass or plastic films). 2.
Transparent anode (usually indium tin oxide, ITO). 3. Hole
transport layer: usually based on triarylamine derivatives. 4.
Matrix and emission layer: this layer consists of a matrix material
usually based on triarylamine derivates, which is doped with the
phosphorescence emitter. 5. Electron transport/hole blocker layer:
usually based on nitrogen-heterocyclene. 6. Electron transport
layer: usually based on aluminium-tris-8-hydroxy-chinoxalinate
(AlQ.sub.3). 7. Cathode: as a rule, use is made here of metals,
metal combinations or metal alloys with a low exit function, such
as for example Al.
[0009] It is also possible to decouple the light from a thin
transparent cathode. These devices are correspondingly structured
(according to the application), contacted and finally also
hermetically sealed, since the life of such devices is as a rule
drastically reduced in the presence of water and/or oxygen.
[0010] The characteristic data of the OLED's described above
reveals two weak points: on the one hand, the previously described
phosphorescence emitters based on tris-orthometallised iridium
complexes are not suitable for the construction of efficient blue
and in particular deep blue OLED's, since none of the known
phosphorescence emitter emits in the deep blue, i.e. at an emission
wavelength .quadrature..sub.max of less than 465 nm.
[0011] Deep blue phosphorescence emitters, however, are of decisive
importance, in particular for the production of full-colour
displays, for which the primary colours RED-GREEN-BLUE must be
available.
[0012] On the other hand, it emerges from the efficiency-luminosity
curves that the efficiency diminishes markedly with increasing
luminosity. This means that the high luminosities required in
practice can only be achieved through a high power input. Large
power inputs, however, require large battery powers of portable
devices (mobile phones, laptops etc.). Furthermore, large power
inputs, which for the most part are converted into heat, lead to
thermal damage of the display.
[0013] The following problems emerge from the shortcomings in the
prior art. On the one hand, there is a need to create, for example,
blue--in particular deep blue--triplet emitters, and on the other
hand triplet emitters must be made available that exhibit
efficiency-luminosity curves that are as linear as possible even in
the presence of high luminosities.
[0014] 5'-Mono-, 5',5''-di- and
5',5'',5'''-tris-cyano-functionalised tris-orthometallised
organo-rhodium and organo-iridium compounds--according to compounds
(I/Ia), (II/IIa), (III/IIIa) or (IV/IVa)--, which are the
subject-matter of the present invention, are central key building
blocks for the production of highly efficient triplet emitters. By
means of a suitable cyano-functionalisation, it is possible to
adjust important material properties, such as the wavelength of the
phosphorescence emission, i.e. the colour, the phosphorescence
quantum yield and the redox and temperature stability of the
emitter, to name but several properties by way of example.
[0015] The class of the 5'-mono-, 5',5''-di- and
5',5'',5'''-tris-cyano-functionalised tris-orthometallised
organo-rhodium and organo-iridium compounds--according to compounds
(I/Ia), (II/IIa), (III/IIIa) or (IV/IVa)--is novel and has not
hitherto been described in the literature, but their efficient
preparation and availability as pure substances is of great
importance for a number of electro-optical applications.
[0016] Surprisingly, it has been found that the wavelength of the
phosphorescence emission of a triplet emitter, i.e. the "colour" of
the emitted light, experiences a hypsochrome shift with the
introduction of cyano-functions in the 5'-, 5''- and 5'''-position
(see table 1).
TABLE-US-00001 TABLE 1 Influence of the 5-substituents on
absorption and phosphorescence Reference to example 1 Example 1
##STR00001## ##STR00002## .lamda..sub.max,Emission
.lamda..sub.max,Emission 535 nm 515 nm green Deep green Reference
to example 2 Example 2 ##STR00003## ##STR00004##
.lamda..sub.max,Emission .lamda..sub.max,Emission 514 nm 464 nm
Deep green Bright blue Reference to example 3 Example 3
##STR00005## ##STR00006## .lamda..sub.max,Emission
.lamda..sub.max,Emission 470 nm 452 nm cyan Deep blue
.lamda..sub.max, Emission: Maximum of the electroluminescence
bands
[0017] Apart from the direct use of 5'-mono-, 5',5''-di- and
5',5'',5'''-tri-cyanofunctionalised tris-orthometallised
organo-rhodium and organo-iridium compounds (according to compounds
(I/Ia), (II/IIa), (III/IIIa) or (IV/IVa)), which are the
subject-matter of the present invention, in light-emitting devices,
said compounds are also central key building blocks for the
production of highly efficient triplet emitters, since the cyano
function can be converted into a large number of functions by
current methods described in the literature. Proceeding from the
known structures, methods known in the literature open up access to
alcohols, amines, aldehydes and carboxylic acids as well as their
derivatives, but also to heterocyclenes such as azolene, diazolene,
triazolene, oxazolinene, oxazolene, oxadiazolene, thiazolene,
thiodiazolene etc. as well as their benzocondensed derivates.
[0018] 5'-mono-, 5',5''-di- and
5',5'',5'''-tri-cyano-tris-orthometallised organo-rhodium and
organo-iridium compounds as well as methods for their preparation
are novel and have not hitherto been described in the literature.
This applies in particular to the cyanisation of halogenated,
aromatic ligands bound to the metal centre, i.e. cyanisation on the
metal complex by substitution of the halogen function by the cyano
function. The efficient preparation and availability of these cyano
compounds as pure substances, however, is of great importance for
various electro-optical applications.
[0019] Surprisingly, it has been found that the new
cyano-substituted organometallic compounds (I/Ia), (II/IIa),
(III/IIIa) or (IV/IVa)--according to scheme 1 and 2--proceeding
from the 5'-mono-, 5',5''-di- and
5',5'',5'''-tri-halogen-substituted tris-orthometallised
organo-rhodium and organo-iridium compounds (V) and (VI)
[preparation according to unpublished DE 10109027.7], i.e.
proceeding from organometallic arylhalogenides--by stoichiometric
conversion with a transition metal cyanide or by catalytic
conversion with a transition metal cyanide, optionally in the
presence of a transition metal, a transition metal compound and a
phosphorus-containing additive, and with a suitable selection of
the reaction parameters such as reaction temperature, reaction
medium, concentration and reaction times, are obtained reproducibly
in an approx. 90-98% yield, without the use of chromatographic
purification processes, optionally after recrystallisation, in
purities of >99% according to NMR and HPLC (see examples
1-6).
[0020] The method described above is characterised in particular by
three properties:
[0021] In the first place, the selective 5'-mono-, 5',5''-di- and
5',5'',5'''-tri-cyanisation of coordinatively bound
arylhalogenides--i.e. of organometallic arylhalogenides--is
unexpected and unknown in this form.
[0022] In the second place, the achieved high conversion, which is
reflected in the reproducibly very good yields of isolated product,
is unexpected and unique to the cyanisation of coordinatively bound
arylhalogenides.
[0023] In the third place, the obtained compounds occur without
costly chromatographic purification, optionally after
recrystallisation, in very good purities of >99% according to
NMR and HPLC. This is essential for use in opto-electronic
components, or more precisely use as intermediate products for the
preparation of suitable compounds.
[0024] As stated above, the compounds according to the invention
have not been described before and are therefore novel.
[0025] The compounds (I) and (II) according to scheme 1 are
therefore the subject-matter of the present invention,
##STR00007##
whereby the symbols and indices have the following meaning:
M Rh, Ir;
[0026] Z is identical or different with each occurrence of N,
CR;
Y O, S, Se;
[0027] R is identical or different with each occurrence of H, F,
Cl, NO.sub.2, CN, a straight-chain or branched or cyclical alkyl or
alkoxy group with 1 to 20 C atoms, whereby one or more
non-neighbouring CH.sub.2 groups can be replaced by --O--, --S--,
--NR.sup.1--, or --CONR.sup.2-- and whereby one or more H atoms can
be replaced by F, or an aryl or heteroaryl group with 4 to 14 C
atoms, which can be substituted by one or more non-aromatic
radicals R; whereby several substituents R, both on the same ring
as well as on the two different rings together, can in turn set up
a further mono- or poly-cyclical ring system; R.sup.1,R.sup.2 are
identical or different, H or an aliphatic or aromatic hydrocarbon
radical with 1 to 20 C atoms; n is 1, 2 or 3
[0028] A further form of embodiment of the invention is represented
by those Rh and Ir complexes which simultaneously have ligands of
the type as in compounds (I) and those of compounds (II), i.e.
mixed ligand systems. These are described by formulas (Ia) and
(IIa)--according to scheme 2:
##STR00008##
whereby the symbols and indices have the meanings stated under
formulas (I) and (II).
[0029] Preference is given to compounds (I), (Ia), (II) and (IIa)
according to the invention, in which S applies to the symbol
Y.dbd.O.
[0030] Also preferred are compounds according to the invention in
which the cycle bound to the metal M by the nitrogen donor atom is
a pyrazine-, pyridazine-, pyrimidine- or triazine-heterocycle.
[0031] Particularly preferred are compounds of the formula (III),
(IV) according to the invention
##STR00009##
[0032] or the further form of embodiment of the invention, i.e.
those rhodium and iridium complexes that simultaneously have
ligands of the type as in compound (III) and those of compound
(IV), i.e. mixed ligand systems, such as described in formulas
(IIIa) and (IVa).
##STR00010##
whereby the symbols and indices have the meanings stated under
formulas (I) and (II) and a is 0, 1, 2, 3 or 4, preferably 0, 1 or
2, particularly preferably 0 or 1; b is 0, 1, 2 or 3, preferably 0
or 1.
[0033] A further subject-matter of the present invention is a
method for the preparation of compounds (I) and (II) by conversion
of compounds (V) and (VI) respectively,
##STR00011##
wherein:
X is Cl, Br or I,
[0034] and M, Z, radicals R and indices a, and b and n have the
meanings stated under compound (I) and (II) respectively, with a
cyanisation agent.
[0035] The method according to the invention is illustrated by
scheme 2:
##STR00012##
[0036] A further subject-matter of the present invention is a
method for the preparation of compounds (III) and (IV), by
conversion of compounds (VII) and (VIII) respectively with a
cyanisation agent, as illustrated in scheme 3.
##STR00013##
[0037] Cyanide sources according to the invention are compounds
that contain the cyanide ion in ionic or coordinatively bound form,
thus for example sodium-, potassium-, magnesium-,
tetraethylammonium-, tetrabutylammonium-, nickel(II)-, copper(I)-,
silver(I)-, zinc(II)-cyanide or sodium- and
potassium-dicyanocuprate(I), -tetracyano-cuprate(II),
-tetracyanozincate(II), -tetracyanonickelate(II),
-tetracyanopalladate(II)
[0038] Preferred cyanisation agents are on the one hand transition
metal cyanides, such as for example copper(I)cyanide or nickel(II)
cyanide. These cyanisation agents are referred to in the following
as cyanisation agents (1).
[0039] A further preferred cyanisation agent is zinc(II)cyanide in
the presence of zinc, and in the presence of nickel or palladium or
a nickel or palladium compound and optionally a
phosphorus-containing additive. These cyanisation agents are
referred to in the following as cyanisation agents (2).
[0040] Nickel or nickel compounds according to the invention for
cyanisation agents (2) are for example elementary nickel, spongy
nickel, nickel on kieselguhr, nickel on aluminium oxide, nickel on
silica, nickel on carbon, nickel(II)acetate,
nickel(II)acetylacetonate, nickel(II)-chloride, -bromide, -iodide,
addition compounds of the type NiL.sub.2X.sub.2 whereby X
corresponds to chlorine, bromine, iodine and L to a neutral ligand
such as for example ammonia, acetonitrile, propionitrile or
benzonitrile, nickel(II) nitrate, nickel(II)sulphate,
nickel(II)oxalate, bis-cyclooctadiennickel(0).
[0041] Palladium or palladium compounds according to the invention
for cyanisation agents (2) are for example elementary palladium,
palladium sponge, palladium black, palladium on active carbon,
palladium on aluminium oxide, palladium on silica, palladium on
alkali- or earth-alkali carbonates such as sodium-, potassium-,
calcium-, strontium- or barium-carbonate, palladium on strontium-
or barium-sulphate, or palladium compounds such as for example
palladium(II)acetate, palladium(II)trifluoroacetate,
palladium(II)propionate, palladium(II)acetylacetonate,
palladium(II)-chloride, -bromide, -iodide, addition compounds of
the type PdL.sub.2X.sub.2 whereby X corresponds to chlorine,
bromine, iodine and L to a neutral ligand such as for example
ammonia, acetonitrile, propionitrile, benzonitrile or
cyclooctadien, palladium(II)nitrate, palladium(II)sulphate,
palladium(II)tetramine acetate,
palladium(II)tetrakis-(acetonitrile)tetrafluoroborate, sodium- and
potassium-tetracyanopalladate,
tetrakis(triphenyl-phosphino)palladium(0) and tris-(dibenzylidene
acetone)-dipalladium(0).
[0042] According to the invention, a phosphine is used as a
phosphorus-containing additive in the case of the cyanisation
agents (2).
[0043] Phosphine ligands according to the invention for cyanisation
agents (2) are from the group of the tri-aryl-phosphines,
di-aryl-alkyl-phosphines, aryl-dialkyl-phosphines,
trialkyl-phosphines, tri-hetaryl-phosphines,
di-hetaryl-alkyl-phosphines, hetaryl-dialkyl-phosphines, whereby
the substituents on the phosphorus can be identical or different,
chiral or achiral, whereby one or more of the substituents can link
the phosphorus groups of several phosphines and whereby a part of
these linkages can also be one or more metal atoms, thus for
example triphenylphosphine, tri-o-tolylphosphine,
tri-mesitylphosphine, tri-o-anisylphosphine,
tri-(2,4,6-trismethoxyphenyl)phosphine,
tent-butyl-di-o-tolylphosphine, di-tert-butyl-o-tolylphosphine,
dicyclohexyl-2-biphenylphosphine,
di-tert-butyl-2-biphenylphosphine, triethylphosphine,
tri-iso-propyl-phosphine, tri-cyclohexylphosphine,
tri-tert-butylphosphine, tri-tert-pentylphosphine,
bis(di-tert-butylphosphino)methane,
1,1'-bis(di-tert-butylphosphino)ferrocene.
[0044] The molar ratio according to the invention for cyanisation
agents (1) and (2) to compounds (III) and (IV) respectively amounts
to 1n:1 to 10n:1, preferably 1.5n:1 to 3n:1.
[0045] The molar ratio according to the invention for
zinc(II)cyanide to zinc in cyanisation agents (2) amounts to 1:0.1
to 1:0.001, preferably 1:0.05 to 1:0.005.
[0046] The molar ratio according to the invention for nickel, a
nickel compound, palladium or a palladium compound to compounds
(III) and (IV) respectively amounts to 0.1n:1 to 0.00001n:1.
[0047] The molar ratio according to the invention for the
phosphorus-containing additive to nickel, a nickel compound,
palladium or a palladium compound amounts to 0.5:1 to 1000:1.
[0048] The reaction media according to the invention are dipolar
aprotic solvents, thus for example nitriles such as acetonitrile,
propionitrile or benzonitrile or N,N-dialkylamides such as
dimethylformamide, dimethylacetamide or N-methylpyrrolidinone,
sulphoxides such as dimethylsulphoxide, sulphones such as
dimethylsulphone or sulpholane.
[0049] According to the invention, the conversion is carried out in
the temperature range from 60.degree. C. to 200.degree. C.,
preferably at 80.degree. C. to 170.degree. C., particularly
preferably at 100.degree. C. to 160.degree. C.
[0050] According to the invention, the concentration of the
rhodium-containing and iridium-containing educts--compounds (III),
(IV), (V) and compounds (VI)--lies in the range from 0.0005 mol/l
to 2 mol/l, particularly preferably in the range from 0.002 mol/l
to 0.1 mol/l.
[0051] According to the invention, the rhodium-containing and
iridium-containing educts may be present dissolved or suspended in
the reaction medium.
[0052] According to the invention, the reaction is carried out
within a period from 1 hour to 100 hours, preferably within a
period from 1 h to 60 h.
[0053] According to the invention, the reaction can be carried out
with the addition of inert ground bodies, such as for example
ceramic, glass or metal balls or Pall or Raschig rings.
[0054] With the methods of synthesis explained here, the examples
of compounds (I), (II), (III) and (IV) represented in the
following, amongst others, can be produced.
##STR00014## ##STR00015## ##STR00016## ##STR00017## ##STR00018##
##STR00019## ##STR00020##
[0055] The iridium and rhodium compounds according to the invention
can be used in electronic components, such as organic light diodes
(OLEDs), organic integrated circuits (O-ICs), organic field-effect
transistors (OFETs), organic thin-film transistors (OTFTs), organic
solar cells (O-SCs), organic laser diodes (O-lasers), organic
colour filters for liquid-crystal displays or organic
photoreceptors. These are also part of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] FIG. 1 graphically depicts the EL spectrum and the
efficiencies as a function of luminosity of the OLED according to
Example 1.
[0057] FIG. 2 graphically depicts the EL spectrum of the OLED
according to Example 3.
[0058] The present invention will be explained in greater detail
with the following examples, without it being intended to be
restricted thereto. From the explanations, the expert is able,
without inventive activity, to produce further complexes according
to the invention and to use the method according to the
invention.
1. Synthesis of Symmetrically and Asymmetrically Functionalised
Tris-Ortho-Metallised Organo-Rhodium and Organo-Iridium
Compounds:
[0059] The following syntheses were carried out--unless indicated
to the contrary--under a protective gas atmosphere in dried
solvent. The educts were procured from ALDRICH [sodium cyanide,
copper(I)cyanide, zinc(II)cyanide, zinc,
tetrakis-(triphenylphosphino)palladium(0), N-methylpyrrolidinone
(NMP)].
fac-tris[2-(2-pyridinyl-.quadrature.N)(5-bromphenyl)-.quadrature.C]-iridi-
um(III),
fac-tris[2-(2-pyridinyl-.quadrature.N)((4-fluor)-5-(brom)phenyl)--
.quadrature.C]-iridium(III),
fac-tris[2-(2-pyridinyl-.quadrature.N)((4,6-fluor)-5-(brom)phenyl)-.quadr-
ature.C]-iridium(III) and
fac-tris[2-(2-pyridinyl-.quadrature.N)((4-methoxy)-5-(brom)phenyl)-.quadr-
ature.C]-iridium(III) was obtained as described in unpublished
application DE 10109027.7.
[0060] The assignment of the .sup.1H-NMR signals was secured in
part by H--H--COSY spectra, that of the .sup.13C{.sup.1H}-NMR
signals in each case via DEPT-135 spectra.
[0061] Numbering scheme for the assignment of the .sup.1H-NMR
signals [according to: C. Coudret, S. Fraysse, J.-P-Launay, Chem.
Commun., 1998, 663-664]:
##STR00021##
EXAMPLE 1
fac-tris[2-(2-pyridinyl-.quadrature.N)(5-cyanophenyl)-.quadrature.C]-iridi-
um(III)
Method A: Use of a Cyanisation Agent 1
[0062] A suspension of 8.915 g (10 mmol)
fac-tris[2-(2-pyridinyl-.quadrature.N)(5-bromphenyl)-.quadrature.C]-iridi-
um(III) and 5.374 g (60 mmol) copper(I)cyanide in 150 ml NMP was
heated to 145.degree. C. for 60 h. After cooling, the brown
solution was poured all at once into a well-stirred, 50.degree. C.
hot solution of 7.4 g sodium cyanide in a mixture of 500 ml water
and 500 ml ethanol and stirred for 2 h at 50.degree. C. The
microcrystalline deposit was then filtered off (P4). The
microcrystalline yellow deposit was washed three times with, in
each case, 100 ml of a solution of 7.4 g sodium cyanide in a
mixture of 500 ml water and 500 ml ethanol, three times with, in
each case, 100 ml of a mixture of ethanol and water (1:1, v v) and
then twice with 100 ml ethanol and then dried in a vacuum
(60.degree. C., 10.sup.-4 mbar). The yield--with a purity of
>99.0% according to .sup.1H-NMR amounted to 7.094-7.236 g
corresponding to 97.2-99.1%.
Method B: Use of a Cyanisation Agent 2
[0063] A suspension of 8.915 g (10 mmol)
fac-tris[2-(2-pyridinyl-.quadrature.N)(5-bromphenyl)-.quadrature.C]-iridi-
um(III), 4.403 g (37.5 mmol) zinc(II)cyanide and 98 mg (1.5 mmol)
zinc dust in 150 ml NMP was mixed with 347 mg (0.3 mmol) and heated
to 100.degree. C. for 60 h. Preparation analogous to method A. The
yield--with a purity of >99.0% according to
.sup.1H-NMR--amounted to 6.877-6.956 g corresponding to
94.2-95.3%.
[0064] .sup.1H-NMR (DMSO-d6): [ppm]=8.41 (d, 1H, .sup.3J.sub.HH=8.4
Hz, H6), 8.31 (s, 1H, H6'), 7.94 (br. dd, 1H, .sup.3J.sub.HH=8.4
Hz, .sup.3J.sub.HH=6.8 Hz, H5), 7.54 (d, 1H, .sup.3J.sub.HH=5.4 Hz,
H3), 7.30 (br. dd, 1H, .sup.3J.sub.HH=6.8 Hz, .sup.3J.sub.HH=5.4
Hz, H4), 7.11 (d, 1H, .sup.3J.sub.HH=8.0 Hz, H4'), 6.74 (d, 1H,
.sup.3J.sub.HH=8.0 Hz, H3').
[0065] .sup.13C{.sup.1H}NMR (DMSO-d6): [ppm]=168.5 (q), 163.0 (q),
147.3 (t), 145.6 (q), 138.3 (t), 136.7 (t), 131.7 (t), 127.3 (t),
124.6 (t), 120.5 (t), 120.4 (q), 102.8 (q).
EXAMPLE 2
fac-tris[2-pyridinyl-.quadrature.N)(4-fluor-5-cyanophenyl)-.quadrature.C]--
iridium(III)
Method A: Use of a Cyanisation Agent 1
[0066] A suspension of 9.455 g (10 mmol)
fac-tris[2-(2-pyridinyl-.quadrature.N)(4-fluor-5-bromphenyl)-.quadrature.-
C]-iridium(III) and 5.374 g (60 mmol) copper(I)cyanide in 200 ml
NMP was heated to 160.degree. C. for 60 h.
[0067] For preparation, see example 1, method A. The yield--with a
purity of >99.0% according to .sup.1H-NMR--amounted to
7.638-7.710 g corresponding to 97.5-98.4%.
[0068] .sup.1H-NMR (DMSO-d6): [ppm]=8.46 (d, 1H, .sup.4J.sub.HF=6.4
Hz, H6'), 8.40 (br. d, 1H, .sup.3J.sub.HH=8.3 Hz, H6), 8.01 (br.
dd, 1H, .sup.3J.sub.HH=8.3 Hz, .sup.3J.sub.HH=7.5 Hz, H5), 7.48
(br. d, 1H, .sup.3J.sub.HH=5.6 Hz, H3), 7.33 (br. dd, 1H,
.sup.3J.sub.HH=7.5 Hz, .sup.3J.sub.HH=5.6 Hz, H4), 6.37 (d, 1H,
.sup.3J.sub.HF=10.05 Hz, H3').
EXAMPLE 3
fac-tris[2-pyridinyl-.quadrature.N)(4,6-difluor-5-cyanophenyl)-.quadrature-
.C]-iridium(III)
Method A: Use of a Cyanisation Agent 1
[0069] A suspension of 9.635 g (10 mmol)
fac-tris[2-(2-pyridinyl-.quadrature.N)(4,6-fluor-5-bromphenyl)-.quadratur-
e.C]-iridium(III) and 5.374 g (60 mmol) copper(I)cyanide in 200 ml
NMP was heated to 160.degree. C. for 60 h.
[0070] For preparation, see example 1, method A. The yield--with a
purity of >99.0% according to .sup.1H-NMR--amounted to
7.638-7.710 g corresponding to 97.5-98.4%. .sup.1H-NMR (DMSO-d6):
[ppm]=8.46 (br. d, 1H, .sup.3J.sub.HH=8.2 Hz, H6), 8.21 (br. dd,
1H, .sup.3J.sub.HH=8.2 Hz, .sup.3J.sub.HH=7.0 Hz, H5), 7.47 (br. d,
1H, .sup.3J.sub.HH=5.8 Hz, H3), 7.30 (br. dd, 1 H,
.sup.3J.sub.HH=7.0 Hz, .sup.3J.sub.HH=5.8 Hz, H4), 6.32 (dd, 1H,
.sup.3J.sub.HF=10.05 Hz, .sup.5J.sub.HF=1.35 Hz H3').
EXAMPLE 4
fac-tris[2-(2-pyridinyl-.quadrature.N)(4-methoxy-5-cyanophenyl)-.quadratur-
e.C]-iridium(III)
Method A: Use of a Cyanisation Agent 1
[0071] A suspension of 9.816 g (10 mmol)
fac-tris[2-(2-pyridinyl-.quadrature.N)(4-methoxy-5-bromphenyl)-.quadratur-
e.C]-iridium(III) and 5.374 g (60 mmol) copper(I)cyanide in 200 ml
NMP was heated to 145.degree. C. for 60 h.
[0072] For preparation, see example 1, method A. The yield--with a
purity of >99.0% according to .sup.1H-NMR--amounted to
7.935-8.030 g corresponding to 96.7-97.9%. .sup.1H-NMR (DMSO-d6):
[ppm]=8.27 (d, 1H, .sup.3J.sub.HH=8.4 Hz, H6), 8.21 (s, 1H, H6'),
7.94 (br. dd, 1H, .sup.3J.sub.HH=8.4 Hz, .sup.3J.sub.HH=6.7 Hz,
H5), 7.54 (d, 1H, .sup.3J.sub.HH=5.1 Hz, H3), 7.30 (br. dd, 1H,
.sup.3J.sub.HH=6.7 Hz, .sup.3J.sub.HH=5.1 Hz, H4), 6.41 (s, 1H,
H3'), 3.48 (s, 3H, CH.sub.3).
2. Production and Characterisation of Organic Electroluminescence
Devices Containing Compounds According to the Invention.
[0073] The production of LEDs took place according to the general
method outlined below. This naturally had to be adapted in the
individual case to the given circumstances (e.g. layer thickness
variation in order to achieve optimum efficiency and colour).
General Method for the Production of OLEDs:
[0074] After the ITO-coated substrates (e.g. glass substrate, PET
film) have been cut to the correct size, they are cleaned in
several cleaning steps in an ultrasonic bath (e.g. soap solution,
millipore water, isopropanol).
[0075] For the purpose of drying, they are blown off with an
N.sub.2-pistol and placed in a desiccator. Before the vapour
deposition with organic layers, they are treated with an
ozone-plasma device for approx. 20 minutes. It may be recommendable
to use a polymer hole-injection layer as a first organic layer. As
a rule, this is a conjugated, conductive polymer, such as for
example a polyaniline derivate (PANI) or a polythiophene derivate
(e.g. PEDOT, BAYTRON P.TM. from BAYER). This is deposited by
spin-coating.
[0076] The organic layers are deposited in turn by vapour
deposition in a high-vacuum installation. The layer thickness of
the respective layer and the vapour deposition rate are monitored
and adjusted by a quartz resonator. As described above, individual
layers can also consist of more than one compound, i.e. as the rule
a host material doped with a guest material. This is achieved by Co
vapour deposition from two or more sources.
[0077] Electrodes are also deposited onto the organic layers. As a
rule, this takes place by thermal vapour deposition (Balzer BA360
or Pfeiffer PL S 500). Contact is then made with the transparent
ITO electrode as the anode and the metal electrode (e.g. Ca, Yb,
Ba--Al) as the cathode and the device parameters are
determined.
EXAMPLE 5
[0078] Analogous to the aforementioned general method, a
blue-emitting OLED with the following structure was produced:
PEDOT 20 nm (spun-on from water; PEDOT procured from BAYER AG;
poly-[3,4-ethylendioxy-2,5-thiophene] MTDATA 20 nm
(vapour-deposited; MTDATA procured from SynTec;
tris-4,4',4''-(3-methylphenyl-phenylamino)triphenylamine) S-TAD 20
nm (vapour-deposited; S-TAD produced according to WO99/12888;
2,2',7,7'-tetrakis(diphenylamino)-spirobifluorene) CPB 20 nm
(vapour-deposited; CPB procured from ALDRICH and further purified,
finally sublimated twice; 4,4'-bis-(N-carbazolyl)biphenyl) doped
with 6% Triplet emitter
fac-tris[2-(2-pyridinyl-.quadrature.N)(4-fluor-5-cyanophenyl)-.quadrature-
.C]-iridium(III)
COMPARE EXAMPLE 3
[0079] BCP 8 nm (vapour-deposited; BCP procured from ABCR, used as
received; 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) AlQ.sub.3
20 nm (vapour-deposited: AlQ.sub.3 procured from SynTec;
tris(chinoxalinato)aluminium(III) Yb 150 nm as the cathode
[0080] These non-optimised OLEDs were characterised as standard;
the EL spectrum is represented in FIG. 1. Apart from the colour, an
enormous advantage of these OLED's is the flatness of the
efficiency curve, which means that very high efficiencies are still
achieved even with very high luminosities (e.g. 10000 Cd/m.sup.2).
This is of decisive importance, above all for use in
passive-matrix-driven displays.
* * * * *