WO2010031738A1

WO2010031738A1 - Electroluminescent metal complexes with azapyrenes

Info

Publication number: WO2010031738A1
Application number: PCT/EP2009/061802
Authority: WO
Inventors: Thomas Schaefer; Kristina Bardon
Original assignee: Basf Se
Priority date: 2008-09-22
Filing date: 2009-09-11
Publication date: 2010-03-25

Abstract

This invention relates to electroluminescent metal complexes with azapyrenes of formula (I), a process for their preparation, electronic devices comprising the metal complexes and their use in electronic devices, especially organic light emitting diodes (OLEDs), as oxygen sensitive indicators, as phosphorescent indicators in bioassays, and as catalysts.

Description

Electroluminescent Metal Complexes with Azapyrenes

This invention relates to electroluminescent metal complexes with azapyrenes, a process for their preparation, electronic devices comprising the metal complexes and their use in electronic devices, especially organic light emitting diodes (OLEDs), as oxygen sensitive indicators, as phosphorescent indicators in bioassays, and as catalysts.

Organic electronic devices that emit light, such as light-emitting diodes that make up displays, are present in many different kinds of electronic equipment. In all such devices, an organic active layer is sandwiched between two electrical contact layers. At least one of the electrical contact layers is light-transmitting so that light can pass through the electrical contact layer. The organic active layer emits light through the light-transmitting electrical contact layer upon application of electricity across the electrical contact layers.

It is well known to use organic electroluminescent compounds as the active component in light-emitting diodes. Simple organic molecules such as anthracene, thiadiazole derivatives, and coumarin derivatives are known to show electroluminescence. Semiconductive conjugated polymers have also been used as electroluminescent components, as has been disclosed in, for example, in US-B-5,247,190, US-B-5,408,109 and EP-A-443 861. Complexes of 8-hydroxyquinolate with trivalent metal ions, particularly aluminum, have been extensively used as electroluminescent components, as has been disclosed in, for example, US-A-5,552,678.

Burrows and Thompson have reported that fac-tris(2-phenylpyridine) iridium can be used as the active component in organic light-emitting devices. (Appl. Phys. Lett. 1999, 75, 4.) The performance is maximized when the iridium compound is present in a host conductive material. Thompson has further reported devices in which the active layer is poly(N-vinyl carbazole) doped with fac-tris[2-(4',5'-difluorophenyl)pyridine-C'²,N]iridium(lll). (Polymer Preprints 2000, 41 (1 ), 770.)

However, there is a continuing need for electroluminescent compounds, especially orange, or, red emitters, having improved performance to provide improved efficiency, stability, manufacturability, or spectral characteristics of electroluminescent devices.

Accordingly the present invention is directed to metal complexes (compounds) of the formula

(I), wherein

Q¹ represents a group of forming a condensed aromatic, or heteroaromatic ring, which can optionally be substituted, L is a mono-, or bi-dentate ligand, n is an integer 1 to 3, m is 0, or an integer 1 to 4 depending on the ligand and the metal, and M is a metal with an atomic weight of greater than 40, especially Fe, Ru, Ni, Co, Ir, Pt, Pd, Rh, Re, or Os,

Y¹, Y², Y³, Y⁴, X¹, X² and X³ are independently each other N, or CR⁴, with the proviso that at least one of the groups X¹, X² and X³ is a group CR⁴, R⁴ is hydrogen, F, -SiR¹⁰⁰R¹⁰¹R¹⁰², or an organic substituent, or any of the substituents R⁴, which are adjacent to each other, together form an aromatic, or heteroaromatic ring, or ring system, which can optionally be substituted, and R¹⁰⁰, R¹⁰¹ and R¹⁰² are independently of each other a Ci-C₈alkyl group, a C₆-C₂₄aryl group, or a C₇-Ci₂aralkylgroup, which may optionally be substituted.

The compounds of the present invention are preferably orange, red or infrared emitters having a λ_max above about 520 nm, especially above about 560 nm and very especially above about 600 nm.

According to the present invention the metal complex comprise at least an azapyrene ligand, i.e. it may comprise two or three or more azapyrene ligands.

The term "ligand" is intended to mean a molecule, ion, or atom that is attached to the coordination sphere of a metallic ion. The term "complex", when used as a noun, is intended to mean a compound having at least one metallic ion and at least one ligand. The term "group" is intended to mean a part of a compound, such a substituent in an organic compound or a ligand in a complex. The term "facial" is intended to mean one isomer of a complex, Ma₃b₃, having octahedral geometry, in which the three "a" groups are all adjacent, i.e. at the corners of one triangular face of the octahedron. The term "meridional" is intended to mean one isomer of a complex, Masbβ, having octahedral geometry, in which the three "a" groups occupy three positions such that two are trans to each other, i.e. the three "a" groups sit in three coplanar positions, forming an arc across the coordination sphere that can be thought of as a meridion. The phrase "adjacent to" when used to refer to layers in a device, does not necessarily mean that one layer is immediately next to another layer. The term

"photoactive" refers to any material that exhibits electroluminescence and/or photosensitivity.

The metal complexes of the present invention are characterized in that at least one ligand is derived from an azapyrene compound. Suitable azapyrenes are known or can be produced according to known procedures. The synthesis of suitable azapyrenes is, for example, described in A. V. Aksenov et al., Tetrahedron Letters (2008) 1808-1811 ; A. V. Aksenov et al., Tetrahedron Letters (2008) 707-709; I. V. Aksenova, et al., Chemistry of Heterocyclic Compounds (2007) 665-666; Till Riehm et al., Chemistry - A European Journal (2007) 7317- 7329; I. V. Borovlev et al., Chemistry of Heterocyclic Compounds (2003) 1417-1442 and PCT/EP2009/057754 as well as the references cited therein.

The metal is generally a metal M with an atomic weight of greater than 40. Preferably the metal M is selected from the group consisting of Fe, Ru, Ni, Co Ir, Pt, Pd, Rh, Re, Os₁TI, Pb, Bi, In, Sn, Sb, Te, Ag and Au. More preferably the metal M is selected from Ir, Rh and Re as well as Pt and Pd, wherein Ir is most preferred.

In a preferred embodiment the present invention is directed to metal complexes represented

by formula (Ia), wherein

Q¹ represents a group of forming a condensed aromatic, or heteroaromatic ring, which can optionally be substituted,

L is a mono-, or bi-dentate ligand, n is an integer 1 to 3, m is 0, or an integer 1 to 4 depending on the ligand and the metal, and

M is a metal with an atomic weight of greater than 40, especially Fe, Ru, Ni, Co, Ir, Pt, Pd, Rh, Re, or Os, wherein X¹ is N, or CR⁴,

FT, FT, R⁴, R³, R 16^b D R7' and R^a are independently of each other hydrogen, F, -SiR 1'0^υ0^υΓR-,1'0^υ1'ΓR-)1'0^υ2% or an organic substituent, or any of the substituents R², R³, R⁴, R⁵, R⁶ R⁷ and R⁸, which are adjacent to each other, together form an aromatic, or heteroaromatic ring, or ring system, which can optionally be substituted, and R¹⁰⁰, R¹⁰¹ and R¹⁰² are independently of each other a Ci-C₈alkyl group, a C₆- C₂₄aryl group, or a C₇-Ci₂aralkylgroup, which may optionally be substituted.

is a group of formula

or , wherein R^41' is the bond to M, R⁷¹ is the bond to M,

R⁴² is hydrogen, or CrC₂₄alkyl, CN, CrC₂₄alkyl, which is substituted by F, halogen, especially F, C₆-Ci₈-aryl, C₆-Ci₈-aryl which is substituted by Ci-Ci₂alkyl, or d-C₈alkoxy, R⁴³ is hydrogen, CN, halogen, especially F, Ci-C₂₄alkyl, which is substituted by F, C₆-Ci₈aryl, C₆-Ci₈aryl which is substituted by C_rCi₂alkyl, or C_rC₈alkoxy, -CONR²⁵R²⁶, -COOR²⁷, E² is -S-, -O-, or -NR^{25 "}-, wherein R^{25 "} is C_rC₂₄alkyl, or C₆-Ci₀aryl, or

R and R are a group of formula

wherein A⁴¹, A⁴", A^4J, A⁴

A⁴⁵, and A⁴⁶ are independently of each other H, halogen, CN, Ci-C₂₄alkyl, d- C₂₄perfluoroalkyl, Ci-C₂₄alkoxy, Ci-C₂₄alkylthio, C₆-Ci₈aryl, which may optionally be substituted by G, -NR²⁵R²⁶, -CONR²⁵R²⁶, or -COOR²⁷, or C₂-Ci₀heteroaryl; especially

R⁴², R⁴³, R⁴⁴ and R⁴⁵ are independently of each other hydrogen, CN or C_rC₂₄alkyl, C_r C₂₄alkyl, which is substituted by F, halogen, especially F, C₆-Ci₈aryl, C₆-Ci₈aryl which is substituted by d-Ci₂alkyl, or Ci-C₈alkoxy, or -L¹-NR²⁵ R 26'

L¹ is a single bond,

, or ml is 0, or 1 ;

R²⁵ and R²⁶ are independently of each other

, or R^25' and R^26' together with the

nitrogen atom to which they are bonded form a group wherein R⁴¹ is H, or Ci-C₈alkyl,

R¹¹⁹ and R¹²⁰ are independently of each other Ci-Cisalkyl, Ci-Ci₈alkyl which is substituted by

E' and/or interrupted by D', C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G', C₂-C₂oheteroaryl,

C₂-C₂₀heteroaryl which is substituted by G', C₂-Ci₈alkenyl, C₂-Ci₈alkynyl, Ci-Ci₈alkoxy, d-

Ci₈alkoxy which is substituted by E' and/or interrupted by D', or C₇-C₂₅aralkyl, or

R¹¹⁹ and R¹²⁰ together form a group of formula =CR¹²¹R¹²², wherein

R¹²¹ and R¹²² are independently of each other H, Ci-Ci₈alkyl, Ci-Ci₈alkyl which is substituted by E' and/or interrupted by D', C6-C₂₄aryl, C₆-C₂₄aryl which is substituted by G', or C₂-

C₂₀heteroaryl, or C₂-C₂₀heteroaryl which is substituted by G', or

R¹¹⁹ and R¹²⁰ together form a five or six membered ring, which optionally can be substituted by Ci-Ci₈alkyl, Ci-Ci₈alkyl which is substituted by E' and/or interrupted by D', C₆-C₂₄aryl, C₆-

C₂₄aryl which is substituted by G', C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by

G', C₂-Ci₈alkenyl, C₂-Ci₈alkynyl, Ci-Ci₈alkoxy, Ci-Ci₈alkoxy which is substituted by E' and/or interrupted by D', C₇-C₂₅aralkyl, or -C(=O)-R¹²⁷, and

R¹²⁷ is H; C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by Ci-Ci₈alkyl, or Ci-Ci₈alkoxy; d-

Ci₈alkyl; or Ci-Ci₈alkyl which is interrupted by -O-,

D' is -CO-, -COO-, -S-, -SO-, -SO₂-, -0-, -NR⁶⁵-, -SiR⁸¹R⁸²-, -POR⁸³-, -CR⁶³=CR⁶⁴-, or -C≡d, and

E' is -OR⁶⁹, -SR⁶⁹, -NR⁶⁵R⁶⁶, -COR⁶⁸, -COOR⁶⁷, -CONR⁶⁵R⁶⁶, -CN, or halogen,

G' is E', or Ci-Ci₈alkyl,

R⁶³, R⁶⁴, R⁶⁵ and R⁶⁶ are independently of each other H; C₆-d₈aryl; C₆-d₈aryl which is substituted by Ci-Ci₈alkyl, Ci-Ci₈alkoxy; Ci-Ci₈alkyl; or Ci-Ci₈alkyl which is interrupted by -O-; or

R⁶⁵ and R⁶⁶ together form a five or six membered ring,

R⁶⁷ and R⁶⁸ are independently of each other C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by d-

Ci₈alkyl, or d-Ci₈alkoxy; Ci-Ci₈alkyl; or Ci-Ci₈alkyl which is interrupted by -O-,

R⁶⁹ is C₆-Ci₈aryl; C₆-Ci₈aryl, which is substituted by Ci-Ci₈alkyl, Ci-Ci₈alkoxy; Ci-Ci₈alkyl; or

Ci-Ci₈alkyl which is interrupted by -O-,

R⁸¹, R⁸² and R⁸³ are independently of each other C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by Ci-Ci₈alkyl, or Ci-Ci₈alkoxy; Ci-Ci₈alkyl; or Ci-Ci₈alkyl which is interrupted by -O-;

R²¹⁶ and R²¹⁷ are independently of each other H, Ci-C₂₅alkyl, which may optionally be interrupted by -O-, or d-C₂5alkoxy;

R⁶⁸ and R⁶⁹ are independently of each other Ci-C₂₄alkyl, especially C₄-Ci₂alkyl, especially hexyl, heptyl, 2-ethylhexyl, and octyl, which can be interrupted by one or two oxygen atoms,

R⁷⁰, R⁷¹, R⁷², R⁷³, R⁷⁴, R⁷⁵, R⁷⁶, R⁹⁰, R⁹¹, R⁹², and R⁹³ are independently of each other H, halogen, especially F, CN, CrC₂₄alkyl, Ci-C₂₄alkyl, which is substituted wholly or partially by

F, C₆-Ci₈aryl, C₆-Ci₈aryl, which is substituted by Ci-Ci₈alkyl, Ci-C₂₄alkoxy, d-

C₂₄alkylthio, -NR²⁵R²⁶, -CONR²⁵R²⁶, or -COOR²⁷, wherein

R²⁵ and R²⁶ are independently of each other d-C₂₅alkyl,

, or R and R together with the nitrogen atom to

which they are bonded form a group , wherein R⁴¹, R²¹⁶ and R²¹⁷ are as defined above,

G is d-Ciβalkyl, -OR³⁰⁵, -SR³⁰⁵, -NR³⁰⁵R³⁰⁶, -CONR³⁰⁵R³⁰⁶, or -CN, wherein R³⁰⁵ and R³⁰⁶ are independently of each other C₆-d₈aryl; C₆-d₈aryl which is substituted by Ci-Ci₈alkyl, or d- Ci₈alkoxy; Ci-Ci₈alkyl, or Ci-Ci₈alkyl which is interrupted by -O-; or

R³⁰⁵ and R³⁰⁶ together form a five or six membered ring, in particular

, or

ore preferred are metal complexes represented by formula

(II), wherein

X¹ is N, or CR⁴,

L is a mono-, or bidentate ligand, n is an integer 1 to 3, m is 0, or an integer 1 to 4 depending on the ligand and the metal, and

M is Fe, Ru, Ni, Co, Ir, Pt, Pd, Rh, Re, or Os, especially Ir, or Pt,

R², R³ and R⁴ are independently of each other hydrogen, CrC₂₄alkyl, CrC₂₄alkoxy, -OR³⁰⁷,

NR^JUbR^Jua, a group

, or

R⁴², R⁴³, R⁴⁴ and R⁴⁵ are independently of each other hydrogen, fluorine, CrC₂₄alkyl, d- C₂₄alkyl, which is substituted wholly, or partially by F, or -L¹-NR²⁵ R^26',

L¹ is a single bond,

, or ml is 0, or 1 ;

R²⁵ and R²⁶ are independently of each other

, or R^25' and R^26' together with the nitrogen atom to which they are bonded form a group

wherein R ,41 is H, or Ci-C₈alkyl,

R¹¹⁶ and R¹¹⁷ are independently of each other H, Ci-C₂₅alkyl, which may optionally be interrupted by -O-, or Ci-C₂5alkoxy, phenyl, or pyridine, which may optionally be substituted by CrC₂5alkyl, which may optionally be interrupted by -O-, or phenyl;

R¹¹⁹ and R¹²⁰ are independently of each other Ci-C₂₅alkyl, which may optionally be interrupted by -O-, or d-C₂5alkoxy;

R²¹⁶ and R²¹⁷ are independently of each other H, Ci-C₂₅alkyl, which may optionally be interrupted by -O-, or d-C₂5alkoxy; and

R³⁰⁷, R³⁰⁸ and R³⁰⁹ are independently of each other C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by Ci-Ci₈alkyl, or Ci-Ci₈alkoxy; CrC₂₄alkyl, or Ci-C₂₄alkyl which is interrupted by -O-.

Even more preferred are metal complexes represented by formula

(Ma), or (Mb), wherein m, L, n, M, R², R³, R⁴, R⁴², R⁴³, R⁴⁴ and R⁴⁵ are as defined above.

In a preferred embodiment the present invention is directed to compounds of formula Ma,

In a preferred embodiment the present invention is directed to compounds of formula Ma, wherein R² and R³ are independently of each other H, C_rC₈alkoxy, -OR³⁰⁷, Or -NR³⁰⁸R³⁰⁹, especially H, Ci-C₈alkoxy, -OPh, OPh, which is substituted by Ci-C₄alkyl;

R⁴ is H,

R⁴², R⁴³, R⁴⁴ and R⁴⁵ are independently of each other H, F, or C_rC₈alkyl, which is substituted wholly, or partially by F, wherein R³⁰⁷, R³⁰⁸ and R³⁰⁹ are independently of each other C_r

C₈alkyl, C₆-Ci₀aryl, or C₆-Ci₀aryl, which is substituted by Ci-C₈alkyl. Compounds of formula Ha are particularly preferred, wherein R² is Ci-C₂₄alkoxy, -OR³⁰⁷, or -

NR³⁰⁸R³⁰⁹, R³, R⁴, R⁴² and R⁴⁴ are H, R⁴³ is F, or C_rC₈alkyl, which is substituted wholly or partially by F, and R⁴⁵ is H, F, or d-Csalkyl, which is substituted wholly or partially by F, wherein R³⁰⁷, R³⁰⁸ and R³⁰⁹ are as defined above.

Compounds of formula Ha are most preferred, wherein

R² is -NR³⁰⁸R³⁰⁹, especially H, Ci-C₂₄alkoxy, or -OR³⁰⁷,

R³ is H,

R⁴ is H, R⁴² is H,

R⁴³ is F, or d-Csalkyl, which is substituted wholly or partially by F,

R⁴⁴ is H; and

R⁴⁵ is H, F, or d-Csalkyl, which is substituted wholly or partially by F, wherein

R³⁰⁷, R³⁰⁸ and R³⁰⁹ are independently of each other C_rC₈alkyl, C₆-Ci₀aryl, or C₆-Ci₀aryl, which is substituted by Ci-C₈alkyl.

Specific examples of compounds of formula Ha are compounds E-32 to E-39, F-32 to E-39, G-32 to G-39, H-32 to H-39, I-32 to I-39 and J-32 to J-39. Reference is made to claim 8.

Monodentate ligands are preferably monoanionic. Such ligands can have O or S as coordinating atoms, with coordinating groups such as alkoxide, carboxylate, thiocarboxylate, dithiocarboxylate, sulfonate, thiolate, carbamate, dithiocarbamate, thiocarbazone anions, sulfonamide anions, and the like. In some cases, ligands such as β-enolates can act as monodentate ligands. The monodentate ligand can also be a coordinating anion such as halide, nitrate, sulfate, hexahaloantimonate, and the like. Examples of suitable monodentate

ligands are shown below:

The monodentate ligands are generally available commercially.

In a preferred embodiment of the present invention the ligand is a (monoanionic) bidentate ligand. In general these ligands have N, O, P, or S as coordinating atoms and form 5- or 6- membered rings when coordinated to the iridium. Suitable coordinating groups include amino, imino, amido, alkoxide, carboxylate, phosphino, thiolate, and the like. Examples of suitable parent compounds for these ligands include β-dicarbonyls (β-enolate ligands), and their N and S analogs; amino carboxylic acids(aminocarboxylate ligands); pyridine carboxylic acids (iminocarboxylate ligands); salicylic acid derivatives (salicylate ligands); hydroxyquinolines (hydroxyquinolinate ligands) and their S analogs; and diarylphosphinoalkanols (diarylphosphinoalkoxide ligands).

Examples of such bidentate ligands L are

, wherein R¹¹ and R¹⁵ are independently of each other hydrogen, CrC₈alkyl, C₆-Ci₈aryl, C₂- Cioheteroaryl, or Ci-C₈perfluoroalkyl, R¹² and R¹⁶ are independently of each other hydrogen, C₆-Ci₈aryl, or d-C₈alkyl, and

R and R are independently of each other hydrogen, d-C₈alkyl, C₆-Ci₈aryl, C₂- Cioheteroaryl, Ci-C₈perfluoroalkyl, or Ci-C₈alkoxy, and R¹⁴ is Ci-C₈alkyl, C₆-Ci₀aryl, or C₇-Cnaralkyl,

R -> 1^ι8^a is C₆-Cioaryl,

R^ηa is Ci-C₈alkyl, C_rC₈perfluoroalkyl,

R ->2^z0^υ is Ci-C₈alkyl, or C₆-Ci₀aryl, R²¹ is hydrogen, Ci-C₈alkyl, or Ci-C₈alkoxy, which may be partially or fully fluorinated, R²² and R²³ are independently of each other C_q(H+F)₂q₊i, or C₆(H+F)_5, R²⁴ can be the same or different at each occurrence and is selected from H, or C_q(H+F)₂q₊i, q is an integer of 1 to 24, p is 2, or 3, and

R⁴⁶ is Ci-C₈alkyl, C₆-Ci₈aryl, or C₆-Ci₈aryl, which is substituted by Ci-C₈alkyl.

Examples of suitable phosphino alkoxide ligands

(WO03040256) are listed below:

3-(diphenylphosphino)-1 -oxypropane [dppO]

1 ,1-bis(trifluoromethyl)-2-(diphenylphosphino)-ethoxide [tfmdpeO].

Examples of particularly suitable compounds HL,

, from which the ligands L are derived, include

(4,4,4-trifluoro-1 -(2-thienyl)-1 ,3-butanedionate

[TTFA]), (7,7-dimethyl-1 ,1 ,1 ,2,2,3,3-heptafluoro-4,6-octanedionate

[FOD]),

(1 ,1 ,1 , 3,5, 5,5-heptafluoro-2, 4-pentanedionate [F7acac]),

(1 ,1 ,1 ,5,5,5-hexafluoro-2,4-pentanedionate [Fθacac]),

( -phenyl-3-methyl-4-i-butyryl-pyrazolinonate [FMBP]), , and

The hydroxyquinoline parent compounds, HL, can be substituted with groups such as alkyl or alkoxy groups which may be partially or fully fluorinated. In general, these compounds are commercially available. Examples of suitable hydroxyquinolinate ligands, L, include: 8-hydroxyquinolinate [8hq] 2-methyl-8-hydroxyquinolinate [Me-8hq] 10-hydroxybenzoquinolinate [10-hbq]

In a further embodiment of the present invention the bidentate ligand L is a ligand of formula

, wherein

the ring A, , represents an optionally substituted aryl group which can optionally contain heteroatoms,

the ring B,

, represents an optionally substituted nitrogen containing aryl group, which can optionally contain further heteroatoms, or the ring A may be taken with the ring B binding to the ring A to form a ring. The preferred ring A includes a phenyl group, a substituted phenyl group, a naphthyl group, a substituted naphthyl group, a furyl group, a substituted furyl group, a benzofuryl group, a substituted benzofuryl group, a thienyl group, a substituted thienyl group, a benzothienyl group, a substituted benzothienyl group, and the like. The substitutent on the substituted phenyl group, substituted naphthyl group, substituted furyl group, substituted benzofuryl group, substituted thienyl group, and substituted benzothienyl group include Ci-C₂₄alkyl groups, C₂-C₂₄alkenyl groups, C₂-C₂₄alkynyl groups, aryl groups, heteroaryl groups, d- C₂₄alkoxy groups, Ci-C₂₄alkylthio groups, a cyano group, C₂-C₂₄acyl groups, d- C₂₄alkyloxycarbonyl groups, a nitro group, halogen atoms, alkylenedioxy groups, and the like.

In said embodiment the bidentate ligand

is preferably a group of formula

wherein R²⁰⁶, R²⁰⁷, R²⁰⁸, and R²⁰⁹ are independently of each other hydrogen, Ci-C₂₄alkyl, C₂-C₂₄alkenyl, C₂-C₂₄alkynyl, aryl, heteroaryl, Ci-C₂₄alkoxy, d- C₂₄alkylthio, cyano, acyl, alkyloxycarbonyl, a nitro group, or a halogen atom; the ring A represents an optionally substituted aryl or heteroaryl group; or the ring A may be taken with the pyridyl group binding to the ring A to form a ring; the alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, alkoxy group, alkylthio group, acyl group, and alkyloxycarbonyl group represented by R²⁰⁶, R²⁰⁷, R²⁰⁸, and R²⁰⁹ may be substituted; or

, wherein

A^41', A^42', A^43', A^44', A^45', and A^46' are independently of each other H, halogen, CN, CrC₂₄alkyl, CrC₂₄perfluoroalkyl, Ci-C₂₄alkoxy, Ci-C₂₄alkylthio, C₆-Ci₈aryl, which may optionally be substituted by G, -NR³¹⁰R³¹¹, -CONR³¹⁰R³¹¹, or -COOR³¹², or C₂-Ci₀heteroaryl; especially

or , wherein R³¹⁰ and R³¹¹ are independently of each other C₆-Ci₈aryl, C₇-Ci₈aralkyl, or Ci-C₂₄alkyl, R³¹² is Ci-C₂₄alkyl, C₆-Ci₈aryl, or C₇-Ci₈aralkyl;

G is d-Ciβalkyl, -OR³⁰⁵, -SR³⁰⁵, -NR³⁰⁵R³⁰⁶, -CONR³⁰⁵R³⁰⁶, or -CN, wherein R³⁰⁵ and R³⁰⁶ are independently of each other C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by CrCi₈alkyl, or d- Ci₈alkoxy; Ci-Ci₈alkyl, or Ci-Ci₈alkyl which is interrupted by -O-.

Examples of preferred classes of such bidentate ligands L are compounds of the formula

, or , especially , or wherein Y is S, O, NR²⁰⁰, wherein R²⁰⁰ is C_rC₄alkyl, C₂-C₄alkenyl, optionally substituted C₆- Cioaryl, especially phenyl, -(CH₂)_r-Ar, wherein Ar is an optionally substituted C₆-Ci₀aryl,

, a group -(CH₂)_rX , wherein r' is an integer of 1 to 5, X is halogen, especially F, or Cl; hydroxy, cyano, -O-Ci-C₄alkyl, di(Ci-C₄alkyl)amino, amino, or cyano; a

group -(CH₂)_rOC(O)(CH₂)_rCH₃, wherein r is 1 , or 2, and r" is 0, or 1 ; — , -NH-Ph, -

C(O)CH₃, -CH₂-O-(CH₂)₂-Si(CH₃)_3! or

Another preferred class of ligands L is described in WO06/000544, of which the following can advantageously be used according to the present invention:

, or , wherein

Q¹ and Q² are independently of each other hydrogen, Ci-C₂₄alkyl, or C₆-Ci₈aryl, A²¹ is hydrogen,

A V 22' is hydrogen, or C₆-Ci₀aryl, A is hydrogen, or C₆-Ci₀aryl,

A V 24' is hydrogen, or

A^23' and A^24', or A^23' and A^24' together form a group

wherein R^205', R^206', R^207' and

R²⁰⁸ are independently of each other H, or d-C₈alkyl, R^42' is H, F, Ci-C₄alkyl, C_rC₈alkoxy, or Ci-C₄perfluoroalkyl, R^43' is H, F, Ci-C₄alkyl, C_rC₈alkoxy, Ci-C₄perfluoroalkyl, or C₆-Ci₀aryl, R⁴⁴ is H, F, Ci-C₄alkyl, d-C₈alkoxy, or Ci-C₄perfluoroalkyl, and R^45' is H, F, Ci-C₄alkyl, C_rC₈alkoxy, or d-C₄perfluoroalkyl.

Another preferred class of bidentate ligands L is a compound of formula

, wherein R²¹⁴ is hydrogen, halogen, especially F, or Cl; Ci-C₄alkyl, d- dperfluoroalkyl, d-dalkoxy, or optionally substituted C₆-Ci₀aryl, especially phenyl, R²¹⁵ is hydrogen, halogen, especially F, or Cl; d-C₄alkyl, d-C₄perfluoroalkyl, optionally substituted C₆-Ci₀aryl, especially phenyl, or optionally substituted C₆-Cioperfluoroaryl, especially C₆F₅,

R²¹⁶ is hydrogen, d-C₄alkyl, d-C₄perfluoroalkyl, optionally substituted C₆-Ci₀aryl, especially phenyl, or optionally substituted C₆-Cioperfluoroaryl, especially C₆F₅, R is hydrogen, halogen, especially F, or Cl; nitro, cyano, Ci-C₄alkyl, Ci-C₄perfluoroalkyl,

Ci-C₄alkoxy, or optionally substituted C₆-Ci₀aryl, especially phenyl,

R²¹⁰ is hydrogen,

R²¹¹ is hydrogen, halogen, especially F, or Cl; nitro, cyano, Ci-C₄alkyl, Ci-C₄alkoxy, C₂-

C₄alkenyl, Ci-C₄perfluoroalkyl, -O-Ci-C₄perfluoroalkyl, tri(Ci-C₄alkyl)silanyl, especially tri(methyl)silanyl, optionally substituted C₆-Ci₀aryl, especially phenyl, or optionally substituted

C₆-Cioperfluoroaryl, especially C₆F₅,

R²¹² is hydrogen, halogen, especially F, or Cl; nitro, hydroxy, mercapto, amino, Ci-C₄alkyl,

C₂-C₄alkenyl, Ci-C₄perfluoroalkyl, Ci-C₄alkoxy, -O-Ci-C₄perfluoroalkyl, -S-Ci-C₄alkyl, tri(d-

C₄alkyl)siloxanyl, optionally substituted -0-C₆-Cioaryl, especially phenoxy, cyclohexyl, optionally substituted C₆-Ci₀aryl, especially phenyl, or optionally substituted C₆-

Cioperfluoroaryl, especially C₆F₅, and

R²¹³ is hydrogen, nitro, cyano, Ci-C₄alkyl, C₂-C₄alkenyl, Ci-C₄perfluoroalkyl, -O-d-

C₄perfluoroalkyl, tri(Ci-C₄alkyl)silanyl, or optionally substituted C₆-Ci₀aryl, especially phenyl.

Specific examples of bidentate ligands L are the following compounds (X-1 ) to (X-57):

(X-1 ), (X-2), (X-3), (X-4), (X-5),

(X-6), (X-7), (X-8), (X-9), (X-10),

(X-12),

(X-13), (X-14),

N (X-15), (X-16), (X-17), (X-18),

(X-22),

(X-23), (X-24), (X-25),

In case of the metal complex (L^a)₂lrL' three isomers can exist.

/i a . __ C U-» N .. i I ,i __ O \J u \

3 L_ o

In some cases mixtures of isomers are obtained. Often the mixture can be used without isolating the individual isomers. The isomers can be separated by conventional methods, as described in A. B. Tamayo et al., J. Am. Chem. Soc. 125 (2003) 7377-7387.

The at present most preferred ligands L are listed below:

Preferences for the bidentate ligand L are given above, wherein the following ligands L are advantageously used:

In a further preferred embodiment of the present invention the metal complex is represented

by formula

(Ma), or (Mb), wherein m is 1 , n is 2, M is Ir,

FT, FT, R⁴, FT, FT, R⁴⁴, R^4b, R¹¹, R^η^ and R^1J are as defined above.

Examples of specific compounds of formula are compounds A-1 to A-31 (claim 8).

Examples of specific compounds of formula are compounds B- 1 to B-31 (claim 8).

Examples of specific compounds of formula are compounds C-1 to C-31 (claim 8).

Examples of specific compounds of formula are compounds D-1 to D-31 (claim 8).

Examples of specific compounds of formula are compounds E-1 to E-31 (claim 8).

Examples of specific compounds of formula are compounds F-1 to F-39 (claim 8).

Examples of specific compounds of formula are compounds G-1 to G-39 (claim 8).

Examples of specific compounds of formula are compounds H-1 to H-39 (claim 8).

Examples of specific compounds of formula are compounds 1-1 to I-39 (claim 8).

Examples of specific compounds of formula are compounds J-1 to J-39 (claim 8).

The metal complexes of the present invention can be prepared according to usual methods known in the prior art. A convenient one-step method for preparing iridium metal complexes

of formula lr(L^a)₃ (L^a =

^Λ ) comprises reacting commercially available iridium trichloride hydrate with an excess of L^aH in the presence of 3 equivalents silver trifluoroacetate and optionally in the presence of a solvent (such as halogen based solvents, alcohol based solvents, ether based solvents, ester based solvents, ketone based solvents, nitrile based solvents, and water). The tris-cyclometalated iridium complexes are isolated and purified by conventional methods. In some cases mixtures of isomers are obtained. Often the mixture can be used without isolating the individual isomers.

The iridium metal complexes of formula lr(L^a)₂L can, for example be prepared by first preparing an intermediate iridium dimer of formula

.L^a i "

, wherein X is H, methyl, or ethyl, and L^a is as defined above, and then addition of HL. The iridium dimers can generally be prepared by first reacting iridium trichloride hydrate with HL^a and adding NaX and by reacting iridium trichloride hydrate with HL^a in a suitable solvent, such as 2-ethoxyethanol. The compounds of formula

are new and form a further aspect of the present invention.

L' a

Compounds of formula

can be synthesized, for example, as outlined in Fig. 7 and 8 of US7166368.

Halogen is fluorine, chlorine, bromine and iodine.

Ci-C₂₄alkyl (Ci-Cisalkyl) is a branched or unbranched radical such as for example methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, 2-ethylbutyl, n-pentyl, isopentyl, 1-methylpentyl, 1 ,3-dimethylbutyl, n-hexyl, 1-methylhexyl, n-heptyl, isoheptyl, 1 ,1 ,3,3- tetramethylbutyl, 1-methylheptyl, 3-methylheptyl, n-octyl, 2-ethylhexyl, 1 ,1 ,3-trimethylhexyl, 1 ,1 ,3,3-tetramethylpentyl, nonyl, decyl, undecyl, 1-methylundecyl, dodecyl, 1 ,1 ,3,3,5,5- hexamethylhexyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, icosyl or docosyl.

Ci-C₂₄perfluoroalkyl is a branched or unbranched radical such as for example - CF₃, -CF₂CF₃, -CF₂CF₂CF₃, -CF(CF₃)₂, -(CF₂)₃CF₃, and -C(CFa)₃. Examples of CrC₂₄alkyl, which is substituted wholly or partially by F, are CHF₂, -

CH₂F, -CH₂CF₃₁ -CF₂CH₃, CF₃, -CF₂CF₃, -CF₂CF₂CF₃, -CF(CF₃)₂, -(CF₂)₃CF₃, and -C(CFa)₃.

Ci-C₂₄alkoxy (Ci-Ci₈alkoxy) radicals are straight-chain or branched alkoxy radicals, e.g. methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, amyloxy, isoamyloxy or tert-amyloxy, heptyloxy, octyloxy, isooctyloxy, nonyloxy, decyloxy, undecyloxy, dodecyloxy, tetradecyloxy, pentadecyloxy, hexadecyloxy, heptadecyloxy and octadecyloxy.

C₂-C₂₄alkenyl (C₂-Cisalkenyl) radicals are straight-chain or branched alkenyl radicals, such as e.g. vinyl, allyl, methallyl, isopropenyl, 2-butenyl, 3-butenyl, isobutenyl, n-penta-2,4-dienyl, 3-methyl-but-2-enyl, n-oct-2-enyl, n-dodec-2-enyl, isododecenyl, n-dodec-2-enyl or n- octadec-4-enyl.

C_2-24alkynyl (C_2-i₈alkynyl) is straight-chain or branched and preferably C_2-8alkynyl, which may be unsubstituted or substituted, such as, for example, ethynyl, 1-propyn-3-yl, 1-butyn-4-yl, 1-pentyn-5-yl, 2-methyl-3-butyn-2-yl, 1 ,4-pentadiyn-3-yl, 1 ,3-pentadiyn-5-yl, 1-hexyn-6-yl, cis-3-methyl-2-penten-4-yn-1 -yl, trans-3-methyl-2-penten-4-yn-1 -yl, 1 ,3-hexadiyn-5-yl, 1-octyn-8-yl, 1-nonyn-9-yl, 1-decyn-10-yl, or 1-tetracosyn-24-yl.

C₄-Ci₈cycloalkyl, especially C₅-Ci₂cycloalkyl, is preferably C₅-Ci₂cycloalkyl or said cycloalkyl substituted by one to three Ci-C₄alkyl groups, such as, for example, cyclopentyl, methyl- cyclopentyl, dimethylcyclopentyl, cyclohexyl, methylcyclohexyl, dimethylcyclohexyl, trimethyl- cyclohexyl, tert-butylcyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cyclododecyl, 1-adamantyl, or 2-adamantyl. Cyclohexyl, 1-adamantyl and cyclopentyl are most preferred.

Examples of C₄-Ci₈cycloalkyl, which is interrupted by S, O, or NR²⁵, are piperidyl, piperazinyl and morpholinyl.

C₂-C₂₄alkenyl is for example vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, or octenyl.

Aryl is usually C₆-C₃₀aryl, preferably C₆-C₂₄aryl (C₆-Ci₈aryl), which optionally can be substituted, such as, for example, phenyl, 4-methylphenyl, 4-methoxyphenyl, naphthyl, biphenylyl, 2-fluorenyl, phenanthryl, anthryl, tetracyl, pentacyl, hexacyl, terphenylyl or quadphenylyl; or phenyl substituted by one to three Ci-C₄alkyl groups, for example o-, m- or p-methylphenyl, 2,3-dimethylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6- dimethylphenyl, 3,4-dimethylphenyl, 3,5-dimethylphenyl, 2-methyl-6-ethylphenyl, 4-tert- butylphenyl, 2-ethylphenyl or 2,6-diethylphenyl.

C₇-C₂₄aralkyl radicals are preferably C₇-Ci₂aralkyl radicals, which may be substituted, such as, for example, benzyl, 2-benzyl-2-propyl, β-phenethyl, α-methylbenzyl, α,α-dimethylbenzyl, ω-phenyl-butyl, ω-phenyl-octyl, ω-phenyl-dodecyl; or phenyl-CrC₄alkyl substituted on the phenyl ring by one to three Ci-C₄alkyl groups, such as, for example, 2-methylbenzyl, 3- methylbenzyl, 4-methylbenzyl, 2,4-dimethylbenzyl, 2,6-dimethylbenzyl or 4-tert-butylbenzyl.or 3-methyl-5-(1 ',1 ',3',3'-tetramethyl-butyl)-benzyl.

Heteroaryl is typically C₂-C₂6heteroaryl (C₂-C₂6heteroaryl), i.e. a ring with five to seven ring atoms or a condensed rig system, wherein nitrogen, oxygen or sulfur are the possible hetero atoms, and is typically an unsaturated heterocyclic radical with five to 30 atoms having at least six conjugated π-electrons such as thienyl, benzo[b]thienyl, dibenzo[b,d]thienyl, thianthrenyl, furyl, furfuryl, 2H-pyranyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, phenoxythienyl, pyrrolyl, imidazolyl, pyrazolyl, pyridyl, bipyridyl, triazinyl, pyrimidinyl, pyrazinyl, pyridazinyl, indolizinyl, isoindolyl, indolyl, indazolyl, purinyl, quinolizinyl, chinolyl, isochinolyl, phthalazinyl, naphthyridinyl, chinoxalinyl, chinazolinyl, cinnolinyl, pteridinyl, carbazolyl, carbolinyl, benzotriazolyl, benzoxazolyl, phenanthridinyl, acridinyl, perimidinyl, phenanthrolinyl, phenazinyl, isothiazolyl, phenothiazinyl, isoxazolyl, furazanyl or phenoxazinyl, which can be unsubstituted or substituted.

C₆-Ci₈cycloalkoxy is, for example, cyclopentyloxy, cyclohexyloxy, cycloheptyloxy or cyclooctyloxy, or said cycloalkoxy substituted by one to three Ci-C₄alkyl, for example, methylcyclopentyloxy, dimethylcyclopentyloxy, methylcyclohexyloxy, dimethylcyclohexyloxy, trimethylcyclohexyloxy, or tert-butylcyclohexyloxy.

C₆-C₂₄aryloxy is typically phenoxy or phenoxy substituted by one to three Ci-C₄alkyl groups, such as, for example o-, m- or p-methylphenoxy, 2,3-dimethylphenoxy, 2,4-dimethylphenoxy, 2,5-dimethylphenoxy, 2,6-dimethylphenoxy, 3,4-dimethylphenoxy, 3,5-dimethylphenoxy, 2- methyl-6-ethylphenoxy, 4-tert-butylphenoxy, 2-ethylphenoxy or 2,6-diethylphenoxy.

C₆-C₂₄aralkoxy is typically phenyl-CrC₉alkoxy, such as, for example, benzyloxy, α- methylbenzyloxy, α,α-dimethylbenzyloxy or 2-phenylethoxy. Ci-C₂₄alkylthio radicals are straight-chain or branched alkylthio radicals, such as e.g. methylthio, ethylthio, propylthio, isopropylthio, n-butylthio, isobutylthio, pentylthio, isopentyl- thio, hexylthio, heptylthio, octylthio, decylthio, tetradecylthio, hexadecylthio or octadecylthio.

Examples of a five or six membered ring formed, for example, by R²⁵ and R²⁶, respectively are heterocycloalkanes or heterocycloalkenes having from 3 to 5 carbon atoms which can have one additional hetero atom selected from nitrogen, oxygen and sulfur, for example

which can be part of a bicyclic system, for

example

or

Possible substituents of the above-mentioned groups are Ci-C₈alkyl, a hydroxyl group, a mercapto group, Ci-C₈alkoxy, Ci-C₈alkylthio, halogen, especially fluorine, halo-CrC₈alkyl, especially fluoro-Ci-C₈alkyl, a cyano group, an aldehyde group, a ketone group, a carboxyl group, an ester group, a carbamoyl group, an amino group, a nitro group or a silyl group.

The term "haloalkyl" means groups given by partially or wholly substituting the above-mentioned alkyl group with halogen, such as trifluoromethyl etc. The "aldehyde group, ketone group, ester group, carbamoyl group and amino group" include those substituted by an Ci-C₂₄alkyl group, a C₄-Ci₈cycloalkyl group, an C₆-C₃oaryl group, an C₇-C₂₄aralkyl group or a heterocyclic group, wherein the alkyl group, the cycloalkyl group, the aryl group, the aralkyl group and the heterocyclic group may be unsubstituted or substituted. The term "silyl group" means a group of formula -SiR¹⁰⁵R¹⁰⁶R¹⁰⁷, wherein R¹⁰⁵, R¹⁰⁶ and R¹⁰⁷ are independently of each other a Ci-C₈alkyl group, in particular a d-C₄ alkyl group, a C₆-C₂₄aryl group or a C₇-Ci₂aralkylgroup, such as a trimethylsilyl group.

If a substituent occurs more than one time in a group, it can be different in each occurrence.

The present invention is also directed to an electronic device comprising the metal complex and its fabrication process. The electronic device can comprise at least one organic active material positioned between two electrical contact layers, wherein at least one of the layers of the device includes the metallic complex compound. The electronic device can comprise an anode layer (a), a cathode layer (e), and an active layer (c). Adjacent to the anode layer (a) is an optional hole-injecting/transport layer (b), and adjacent to the cathode layer (e) is an optional electron-injection/transport layer (d). Layers (b) and (d) are examples of charge transport layers.

The active layer (c) can comprise at least approximately 0.1 weight percent of metal complex previously described.

In some embodiments, the active layer (c) may be substantially 100% of the metal complex because a host charge transporting material, such as AIq₃ is not needed. By "substantially 100%" it is meant that the metal complex is the only material in the layer, with the possible exception of impurities or adventitious by-products from the process to form the layer. Still, in some embodiments, the metal complex may be a dopant within a host material, which is typically used to aid charge transport within the active layer (c). The active layer (c), including any of the metal complexes, can be a small molecule active material.

The device may include a support or substrate (not shown) adjacent to the anode layer (a) or the cathode layer (e). Most frequently, the support is adjacent the anode layer (a). The support can be flexible or rigid, organic or inorganic. Generally, glass or flexible organic films are used as a support. The anode layer (a) is an electrode that is more efficient for injecting holes compared to the cathode layer (e). The anode can include materials containing a metal, mixed metal, alloy, metal oxide or mixed-metal oxide. Suitable metal elements within the anode layer (a) can include the Groups 4, 5, 6, and 8-1 1 transition metals. If the anode layer (a) is to be light transmitting, mixed-metal oxides of Groups 12, 13 and 14 metals, such as indium-tin-oxide, may be used. Some non-limiting, specific examples of materials for anode layer (a) include indium-tin-oxide ("ITO"), aluminum-tin-oxide, gold, silver, copper, nickel, and selenium.

The anode layer (a) may be formed by a chemical or physical vapor deposition process or spin-cast process. Chemical vapor deposition may be performed as a plasma-enhanced chemical vapor deposition ("PECVD") or metal organic chemical vapor deposition ("MOCVD"). Physical vapor deposition can include all forms of sputtering (e. g., ion beam sputtering), e- beam evaporation, and resistance evaporation.

Specific forms of physical vapor deposition include rf magnetron sputtering or inductively- coupled plasma physical vapor deposition("ICP- PVD"). These deposition techniques are well-known within the semiconductor fabrication arts.

A hole-transport layer (b) may be adjacent the anode. Both hole transporting small molecule compounds and polymers can be used.

Commonly used hole transporting molecules, in addition to N,N'-diphenyl- N,N'-bis (3- methylphenyl)-[1 ,1 '-biphenyl]-4, 4'-diamine (TPD) and bis [4-(N,N-diethylamino)-2- methylphenyl] (4-methylphenyl) methane(MPMP), include : polyvinyl-carbazol, 1 ,1-bis[(di-4- tolylamino)phenyl]cyclohexane (TAPC); N,N'-bis(4-methylphenyl)-N,N'-bis(4-ethylphenyl)- [1 ,1 '-(3,3'-dimethyl) biphenyl]-4,4'-diamine (ETPD); tetrakis-(3-methylphenyl)-N,N,N',N'-2,5- phenylenediamine (PDA); a-phenyl-4-N,N-diphenylaminostyrene (TPS); p- (diethylamino)benzaldehyde diphenylhydrazone (DEH); triphenylamine (TPA); 1-phenyl-3-[p- (diethylamino)styryl]-5-[p-(diethylamino)phenyl]pyrazoline (PPR or DEASP); 1 ,2-trans- bis(9H-carbazol-9-yl)cyclobutane (DCZB); N,N,N',N'-tetrakis(4-methylphenyl)-(1 ,1'-biphenyl)- 4, 4'-diamine (TTB); N,N'-di-α-naphthyl-N,N'-diphenyl-4,4'-diphenyldiamine (α-NPD), and porphyrinic compounds, such as copper phthalocyanine.

Commonly used hole transporting polymers are polyvinylcarbazole, (phenylmethyl) polysilane, poly(3,4-ethylendioxythiophene) (PEDOT), and polyaniline. Hole-transporting polymers can be obtained by doping hole-transporting molecules such as those mentioned above into polymers such as polystyrene and polycarbonate.

The hole-injection/transport layer (b) can be formed using any conventional means, including spin-coating, casting, and printing, such as gravure printing. The layer can also be applied by ink jet printing, thermal patterning, or chemical, or physical vapor deposition.

Usually, the anode layer (a) and the hole-injection/transport layer (b) are patterned during the same lithographic operation. The pattern may vary as desired. The layers can be formed in a pattern by, for example, positioning a patterned mask or resist on the first flexible composite barrier structure prior to applying the first electrical contact layer material. Alternatively, the layers can be applied as an overall layer (also called blanket deposit) and subsequently patterned using, for example, a patterned resist layer and wet-chemical or dry-etching techniques. Other processes for patterning that are well known in the art can also be used. When the electronic devices are located within an array, the anode layer (a) and hole injection/transport layer (b) typically are formed into substantially parallel strips having lengths that extend in substantially the same direction.

The active layer (c) may comprise the metal complexes described herein. The particular material chosen may depend on the specific application, potentials used during operation, or other factors. The active layer (c) may comprise a host material capable of transporting electrons and/or holes, doped with an emissive material that may trap electrons, holes, and/ or excitons, such that excitons relax from the emissive material via a photoemissive mechanism. Active layer (c) may comprise a single material that combines transport and emissive properties. Whether the emissive material is a dopant or a major constituent, the active layer may comprise other materials, such as dopants that tune the emission of the emissive material. Active layer (c) may include a plurality of emissive materials capable of, in combination, emitting a desired spectrum of light. Examples of phosphorescent emissive materials include the metal complexes of the present invention. Examples of fluorescent emissive materials include DCM and DMQA. Examples of host materials include AIq₃, BAIq, BAIq₂ (Appl. Phys. Lett. 89 (2006) 061 11 1 ), CBP and mCP. Examples of emissive and host materials are disclosed in US-B-6, 303,238, which is incorporated by reference in its entirety.

The active layer (c) can be applied from solutions by any conventional technique, including spin coating, casting, and printing. The active organic materials can be applied directly by vapor deposition processes, depending upon the nature of the materials.

Optional layer (d) can function both to facilitate electron injection/transport, and also serve as a buffer layer or confinement layer to prevent quenching reactions at layer interfaces. More specifically, layer (d) may promote electron mobility and reduce the likelihood of a quenching reaction if layers (c) and (e) would otherwise be in direct contact. Examples of materials for optional layer (d) include metal-cheated oxinoid compounds (e. g., AIq₃ or the like); phenanthroline-based compounds (e. g., 2,9-dimethyl-4,7-diphenyl-1 ,10-phenanthroline ("DDPA"), 4,7-diphenyl-1 ,10-phenanthroline ("DPA"), or the like; azole compounds (e. g., 2- (4-biphenylyl)-5-(4-t-butylphenyl)-1 ,3,4-oxadiazole ("PBD") or the like, 3-(4-biphenylyl)-4- phenyl-5-(4-t-butylphenyl)-1 ,2,4-triazole ("TAZ") or the like; other similar compounds; or any one or more combinations thereof. Alternatively, optional layer (d) may be inorganic and comprise BaO, LiF, Li₂O, or the like. The electron injection/transport layer (d) can be formed using any conventional means, including spin-coating, casting, and printing, such as gravure printing. The layer can also be applied by ink jet printing, thermal patterning, or chemical or physical vapor deposition.

The cathode layer (e) is an electrode that is particularly efficient for injecting electrons or negative charge carriers. The cathode layer (e) can be any metal or nonmetal having a lower work function than the first electrical contact layer (in this case, the anode layer (a)). Materials for the second electrical contact layer can be selected from alkali metals of Group 1 (e. g., Li, Na, K, Rb, Cs), the Group 2 (alkaline earth) metals, the Group 12 metals, the rare earths, the lanthanides (e. g. , Ce, Sm, Eu, or the like), and the actinides. Materials, such as aluminum, indium, calcium, barium, yttrium, and magnesium, and combinations thereof, may also be used. Li-containing organometallic compounds, LiF, and Li₂O can also be deposited between the organic layer and the cathode layer to lower the operating voltage. Specific non- limiting examples of materials for the cathode layer (e) include barium, lithium, cerium, cesium, europium, rubidium, yttrium, magnesium, or samarium.

The cathode layer (e) is usually formed by a chemical or physical vapor deposition process. In general, the cathode layer will be patterned, as discussed above in reference to the anode layer (a) and optional hole injecting layer (b). If the device lies within an array, the cathode layer (e) may be patterned into substantially parallel strips, where the lengths of the cathode layer strips extend in substantially the same direction and substantially perpendicular to the lengths of the anode layer strips.

Electronic elements called pixels are formed at the cross points (where an anode layer strip intersects a cathode layer strip when the array is seen from a plan or top view).

In other embodiments, additional layer (s) may be present within organic electronic devices. For example, a layer (not shown) between the hole injecting layer (b) and the active layer (c) may facilitate positive charge transport, band-gap matching of the layers, function as a protective layer, or the like. Similarly, additional layers (not shown) between the electron injecting layer (d) and the cathode layer (e) may facilitate negative charge transport, band- gap matching between the layers, function as a protective layer, or the like. Layers that are known in the art can be used. Some or all of the layers may be surface treated to increase charge carrier transport efficiency. The choice of materials for each of the component layers may be determined by balancing the goals of providing a device with high device efficiency with the cost of manufacturing, manufacturing complexities, or potentially other factors.

The charge transport layers (b) and (d) are generally of the same type as the active layer (c). More specifically, if the active layer (c) has a small molecule compound, then the charge transport layers (b) and (d), if either or both are present, can have a different small molecule compound. If the active layer (c) has a polymer, the charge transport layers (b) and (d), if either or both are present, can also have a different polymer. Still, the active layer (c) may be a small molecule compound, and any of its adjacent charge transport layers may be polymers.

Each functional layer may be made up of more than one layer. For example, the cathode layer may comprise a layer of a Group 1 metal and a layer of aluminum. The Group 1 metal may lie closer to the active layer (c), and the aluminum may help to protect the Group 1 metal from environmental contaminants, such as water.

Although not meant to limit, the different layers may have the following range of thicknesses: inorganic anode layer (a), usually no greater than approximately 500 nm, for example, approximately 50-200 nm; optional hole-injecting layer (b), usually no greater than approximately 100 nm, for example, approximately 50-200 nm; active layer (c), usually no greater than approximately 100 nm, for example, approximately 10-80 nm; optional electron- injecting layer (d), usually no greater than approximately 100 nm, for example, approximately 10-80 nm; and cathode layer (e), usually no greater than approximately 1000 nm, for example, approximately 30-500 nm. If the anode layer (a) or the cathode layer (e) needs to transmit at least some light, the thickness of such layer may not exceed approximately 100 nm.

The location of the electron-hole recombination zone in the device, and thus the emission spectrum of the device, can be affected by the relative thickness of each layer. For example, when a potential light-emitting compound, such as AIq₃ is used in the electron transport layer (d), the electron-hole recombination zone can lie within the AIq₃ layer.

The emission would then be that Of AIq₃, and not a desired sharp emission. Thus, the thickness of the electron-transport layer should be chosen so that the electron-hole recombination zone lies within the light-emitting layer (i. e., active layer (c)). The desired ratio of layer thicknesses can depend on the exact nature of the materials used. The efficiency of the devices made with metal complexes can be further improved by optimizing the other layers in the device. For example, more efficient cathodes such as Ca, Ba, Mg/Ag, orLiF/AI can be used. Shaped substrates and hole transport materials that result in a reduction in operating voltage or increase quantum efficiency are also applicable. Additional layers can also be added to tailor the energy levels of the various layers and facilitate electroluminescence.

Depending upon the application of the electronic device, the active layer (c) can be a light- emitting layer that is activated by a signal (such as in a light-emitting diode) or a layer of material that responds to radiant energy and generates a signal with or without an applied potential (such as detectors or voltaic cells). Examples of electronic devices that may respond to radiant energy are selected from photoconductive cells, photoresistors, photoswitches, phototransistors, and phototubes, and photovoltaic cells. After reading this specification, skilled artisans will be capable of selecting material (s) that for their particular applications.

In OLEDs, electrons and holes, injected from the cathode (e) and anode (a) layers, respectively, into the photoactive layer (c), form negative and positively charged polarons in the active layer (c). These polarons migrate under the influence of the applied electric field, forming a polaron exciton with an oppositely charged species and subsequently undergoing radiative recombination. A sufficient potential difference between the anode and cathode, usually less than approximately 20 volts, and in some instances no greater than approximately 5 volts, may be applied to the device. The actual potential difference may depend on the use of the device in a larger electronic component. In many embodiments, the anode layer (a) is biased to a positive voltage and the cathode layer (e) is at substantially ground potential or zero volts during the operation of the electronic device. A battery or other power source (s) may be electrically connected to the electronic device as part of a circuit.

In other embodiments, the metal complex compound can be used as a charge transport material in layer (b) or (d).

The compound does not need to be in a solid matrix diluent (e. g., host charge transport material) when used in layer (b) (c), or (d) in order to be effective. A layer greater than approximately 0.1 % by weight of the metal complex compound, based on the total weight of the layer, and up to substantially 100% of the complex compound can be used as the active layer (c). Additional materials can be present in the active layer (c) with the complex compound. For example, a fluorescent dye may be present to alter the color of emission.

A diluent may also be added. The diluent can be a polymeric material, such as poly (N-vinyl carbazole) and polysilane. It can also be a small molecule, such as 4,4'-N, N'-dicarbazole biphenyl or tertiary aromatic amines. When a diluent is used, the complex compound is generally present in a small amount, usually less than 20% by weight, preferably less than 10% by weight, based on the total weight of the layer.

The metallic complexes may be used in applications other than electronic devices. For example, the complexes may be used as catalysts or indicators (e. g., oxygen-sensitive indicators, phosphorescent indicators in bioassays, or the like).

Various features and aspects of the present invention are illustrated further in the examples that follow. While these examples are presented to show one skilled in the art how to operate within the scope of this invention, they are not to serve as a limitation on the scope of the invention where such scope is only defined in the claims. Unless otherwise indicated in the following examples and elsewhere in the specification and claims, all parts and percentages are by weight, temperatures are in degrees centigrade and pressures are at or near atmospheric.

EXAMPLES

Example 1

a) 26.4 g (0.139 mol) sodium pyrosulfite (Na₂S₂O₅) are added to 20.0 g (0.126 mol) naphthalene-1 ,8-diamine and 14.8 g (0.139 mol) benzaldehyde in 160 ml ethanol. The reaction mixture is refluxed for 23 h under nitrogen and is then cooled to 25 ⁰C. The product is filtered off, washed with ethanol and water. The product is used for the next reaction without further purification. Yield: 20.4 g (66 %)

b) 10.2 g (49.1 mmol) (E)-1 ,3-diphenyl-propenone are added to 10.0 g (40.9 mmol) of the product of example 1a). 100 ml poly phosphoric acid (PPA) and 5 ml toluene are added and the reaction mixture is stirred at 100 ⁰C for 17 h under nitrogen. 60 ml water are added to the reaction mixture and the reaction mixture is stirred for 30 min. The reaction mixture is poured into 200 ml water and is neutralized with aqueous ammonia. The product is filtered off and is washed with water and ethanol. Soxhlet extraction with ethyl acetate gives after column chromatography with toluene on silica gel the product in 35 % (6.1 1g) yield. Melting point: 275 ⁰C

c) 50 ml ethoxyethanol are added to 2.00 g (4.62 mmol) of the product of example 1 b) and 0.81 g (2.22 mmol) iridium(lll) chloride hydrate. The reaction mixture is stirred under nitrogen at 120 ⁰C for 24 h and is then cooled to 25 ⁰C. 20 ml water are added to the reaction mixture and the product is filtered off. The product is washed with ethanol and ethyl acetate and is used without purification for the next reaction step.

nol

d) 1.12 g (10.5 mmol) sodium carbonate are added to 2.30 g (1.05 mmol) of the product of example 1 c) and 530 mg (5.27 mmol) pentane-2,4-dione. 50 ml ethoxyethanol are added and the reaction mixture is stirred for 24 h at 120 ⁰C under nitrogen, cooled to 25 ⁰C and 20 ml water are added. The product is filtered off and is washed with ethanol and ethyl acetate. The product is filtered on hyfo first with ethyl acetate and than with chloroform. The solvent of the chloroform fraction is removed until 15 ml are left. 60 ml ethyl acetate are added and the product is filtered off. Yield 1.61 g (66 %).

Claims

1. A metal complex of formula

(I), wherein

Y¹, Y², Y³, Y⁴, X¹, X² and X³ are independently each other N, or CR⁴, with the proviso that at least one of the groups X¹, X² and X³ is a group CR⁴, R⁴ is hydrogen, F, -SiR¹⁰⁰R¹⁰¹R¹⁰², or an organic substituent, or any of the substituents R⁴, which are adjacent to each other, together form an aromatic, or heteroaromatic ring, or ring system, which can optionally be substituted, and R¹⁰⁰, R¹⁰¹ and R¹⁰² are independently of each other a C_rC₈alkyl group, a C₆-C₂₄aryl group, or a C₇-Ci₂aralkylgroup, which may optionally be substituted.

A metal complex according to claim 1 , wherein the metal complex is represented by

formula (Ia), wherein Q¹ represents a group of forming a condensed aromatic, or heteroaromatic ring, which can optionally be substituted,

L is a mono-, or bi-dentate ligand, n is an integer 1 to 3, m is 0, an integer 1 to 4 depending on the ligand and the metal, and

M is a metal with an atomic weight of greater than 40, especially Fe, Ru, Ni, Co, Ir, Pt,

Pd, Rh, Re, or Os, wherein X¹ is N, or CR⁴,

R², R³, R⁴, R⁵, R⁶ R⁷ and R⁸ are independently of each other hydrogen,

F, -SiR¹⁰⁰R¹⁰¹R¹⁰², or an organic substituent, or any of the substituents R², R³, R⁴, R⁵, R⁶ R⁷ and R⁸, which are adjacent to each other, together form an aromatic, or heteroaromatic ring, or ring system, which can optionally be substituted, and R¹⁰⁰, R¹⁰¹ and R¹⁰² are independently of each other a C_rC₈alkyl group, a C₆-C₂₄aryl group, or a C₇-Ci₂aralkylgroup, which may optionally be substituted.

A metal complex of formula according to claim 1 , or 2, wherein

is a group of formula

, wherein

R⁴¹ is the bond to M,

R ₅7"1 is the bond to M,

R⁴² is hydrogen, or CrC₂₄alkyl, CN, CrC₂₄alkyl, which is substituted by F, halogen, especially F, C₆-Ci₈-aryl, C₆-Ci₈-aryl which is substituted by Ci-Ci₂alkyl, or d-C₈alkoxy,

R⁴³ is hydrogen, CN, halogen, especially F, Ci-C₂₄alkyl, which is substituted by F, C₆-

Ci₈aryl, C₆-Ci₈aryl which is substituted by Ci-Ci₂alkyl, or d-

C₈alkoxy, -CONR²⁵R²⁶, -COOR²⁷, wherein

E² is -S-, -O-, or -NR^{25 "}-, wherein R^{25 "} is C_rC₂₄alkyl, or C₆-Ci₀aryl, or R⁴² and R⁴³ are a group of formula

wherein A⁴¹, A⁴² A⁴³,

A⁴⁴, A⁴⁵, and A⁴⁶ are independently of each other H, halogen, CN, Ci-C₂₄alkyl, C_r C₂₄perfluoroalkyl, CrC₂₄alkoxy, Ci-C₂₄alkylthio, C₆-Ci₈aryl, which may optionally be substituted by G, -NR²⁵R²⁶, -CONR²⁵R²⁶, or -COOR²⁷, or C₂-Ci₀heteroaryl; especially

R ₃4₂ , _D R43 , o R44 _ and,j _D R45 are independently of each other hydrogen, CN or C_rC₂₄alkyl, C_r C₂₄alkyl, which is substituted by F, halogen, especially F, C₆-Ci₈aryl, C₆-Ci₈aryl which is substituted by C_rCi₂alkyl, or C_rC₈alkoxy, or -L¹-NR²⁵ R^26',

L¹ is a single bond, , or

; R²⁵ and R²⁶ are independently of each other

, or R^25' and R^26' together with the

nitrogen atom to which they are bonded form a group wherein

R⁴¹ is H, or Ci-C₈alkyl,

R¹¹⁹ and R¹²⁰ are independently of each other Ci-Ci₈alkyl, Ci-Ci₈alkyl which is substituted by E' and/or interrupted by D', C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by

G', C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by G', C₂-Ci₈alkenyl, C₂-

Ci₈alkynyl, Ci-Ci₈alkoxy, Ci-Ci₈alkoxy which is substituted by E' and/or interrupted by

D', or C₇-C₂₅aralkyl, or

R¹¹⁹ and R¹²⁰ together form a group of formula =CR¹²¹R¹²², wherein R¹²¹ and R¹²² are independently of each other H, Ci-Cisalkyl, Ci-Ci₈alkyl which is substituted by E' and/or interrupted by D', C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by

G', or C₂-C₂oh eteroary I, or C₂-C₂₀heteroaryl which is substituted by G', or

R¹¹⁹ and R¹²⁰ together form a five or six membered ring, which optionally can be substituted by Ci-Ci₈alkyl, d-Ci₈alkyl which is substituted by E' and/or interrupted by

D', C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G', C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by G', C₂-Ci₈alkenyl, C₂-Ci₈alkynyl, Ci-Ci₈alkoxy, Ci-Ci₈alkoxy which is substituted by E' and/or interrupted by D', C₇-C₂₅aralkyl, or -C(=O)-R¹²⁷, and

R¹²⁷ is H; C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by Ci-Ci₈alkyl, or Ci-Ci₈alkoxy; d- Ci₈alkyl; or Ci-Ci₈alkyl which is interrupted by -O-,

D' is -CO-, -COO-, -S-, -SO-, -SO₂-, -O-, -NR⁶⁵-, -SiR⁸¹R⁸²-, -POR⁸³-, -CR⁶³=CR⁶⁴-, or -

C≡C-, and

G' is E', or Ci-Ci₈alkyl, R⁶³, R⁶⁴, R⁶⁵ and R⁶⁶ are independently of each other H; C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by Ci-Ci₈alkyl, Ci-Ci₈alkoxy; Ci-Ci₈alkyl; or Ci-Ci₈alkyl which is interrupted by -0-; or

R⁶⁵ and R⁶⁶ together form a five or six membered ring,

R⁶⁷ and R⁶⁸ are independently of each other C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by Ci-Ci₈alkyl, or Ci-Ci₈alkoxy; Ci-Ci₈alkyl; or Ci-Ci₈alkyl which is interrupted by -0-,

R⁶⁹ is C₆-Ci₈aryl; C₆-Ci₈aryl, which is substituted by Ci-Ci₈alkyl, Ci-Ci₈alkoxy; d-

Ci₈alkyl; or Ci-Ci₈alkyl which is interrupted by -0-,

R²¹⁶ and R²¹⁷ are independently of each other H, Ci-C₂₅alkyl, which may optionally be interrupted by -0-, or Ci-C₂₅alkoxy; R⁶⁸ and R⁶⁹ are independently of each other Ci-C₂₄alkyl, especially C₄-Ci₂alkyl, especially hexyl, heptyl, 2-ethylhexyl, and octyl, which can be interrupted by one or two oxygen atoms,

R⁷⁰, R⁷¹, R⁷², R⁷³, R⁷⁴, R⁷⁵, R⁷⁶, R⁹⁰, R⁹¹, R⁹², and R⁹³ are independently of each other H, halogen, especially F, CN, Ci-C₂₄alkyl, Ci-C₂₄alkyl, which is substituted wholly or partially by F,

C₆-Ci₈aryl, or C₆-Ci₈aryl, which is substituted by Ci-Ci₈alkyl, Ci-C₂₄alkoxy, d- C₂₄alkylthio, -NR²⁵R²⁶, -CONR²⁵R²⁶, or -COOR²⁷, wherein R and R are independently of each other Ci-C₂₅alkyl,

, or R²⁵ and R²⁶ together with the nitrogen atom

to which they are bonded form a group

wherein R⁴¹, R^^ηb and

R ₃217 are as defined above,

R^ is Ci-C₂₄alkyl, C₆-Ci₈aryl, or C₇-Ci₈aralkyl;

G is Ci-Ci₈alkyl, -OR^dυb, -SR^dυb, -NR^dυbR^dυb, -CONR^dυbR^dυb, or -CN, wherein R^dυb and

R are independently of each other C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by d- Ci₈alkyl, or Ci-Ci₈alkoxy; Ci-Ci₈alkyl, or Ci-Ci₈alkyl which is interrupted by -O-; or

4. The metal complex according to any of claims 1 to 3, wherein the metal M is selected from the group consisting of Ir and Pt.

5. The metal complex according to any of claims 1 to 4, wherein the metal complex is

represented by formula (II), wherein

X¹ is N, or CR⁴,

L is a mono-, or bidentate ligand, n is an integer 1 to 3, m is 0, an integer 1 to 4 depending on the ligand and the metal, and

M is Fe, Ru, Ni, Co, Ir, Pt, Pd, Rh, Re, or Os, especially Ir, or Pt,

R², R³ and R⁴ are independently of each other hydrogen, Ci-C₂₄alkyl, -OR³⁰⁷,

NR³⁰⁸R³⁰⁹,

a group

or

R⁴², R⁴³, R⁴⁴ and R⁴⁵ are independently of each other hydrogen, fluorine, CrC₂₄alkyl, Ci-C₂₄alkyl, which is substituted wholly, or partially by F, or -L¹-NR²⁵ R^26',

L¹ is a single bond, , or

;

R and R are independently of each other

wherein

R⁴¹ is H, or d-Cβalkyl,

R¹¹⁶ and R¹¹⁷ are independently of each other H, Ci-C₂5alkyl, which may optionally be interrupted by -O-, or Ci-C₂₅alkoxy, or phenyl, which may optionally be substituted by

Ci-C₂₅alkyl, which may optionally be interrupted by -O-, or phenyl;

R¹¹⁹ and R¹²⁰ are independently of each other Ci-C₂5alkyl, which may optionally be interrupted by -O-, or C_rC₂₅alkoxy;

R²¹⁶ and R²¹⁷ are independently of each other H, Ci-C₂₅alkyl, which may optionally be interrupted by -O-, or Ci-C₂₅alkoxy, and

R³⁰⁷, R³⁰⁸ and R³⁰⁹ are independently of each other C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by Ci-Ci₈alkyl, or d-Ci₈alkoxy; CrC₂₄alkyl, or Ci-C₂₄alkyl which is interrupted by -O-.

6. The metal complex according to claim 5, wherein the metal complex is represented by

formula

(Ha), or (Mb), wherein m, L, n, M, R^, R^ά, R⁴, R⁴% R^4J, R⁴⁴ and R^4b are as defined in claim 5.

7. The metal complex according to any of claims 1 to 6, wherein the bidentate ligand L is

a compound of formula

, wherein the ring A, , represents an optionally substituted aryl group which can optionally contain heteroatoms, the ring B,

, represents an optionally substituted nitrogen containing aryl group, which can optionally contain further heteroatoms, or the ring A may be taken with the ring B binding to the ring A to form a ring; especially a group of formula

, wherein R²⁰⁶, R²⁰⁷, R²⁰⁸, and R²⁰⁹ are independently of each other hydrogen, CrC₂₄alkyl, C₂-C₂₄alkenyl, C₂-C₂₄alkynyl, aryl, heteroaryl, Ci-C₂₄alkoxy, Ci-C₂₄alkylthio, cyano, acyl, alkyloxycarbonyl, a nitro group, or a halogen atom; the ring A represents an optionally substituted aryl or heteroaryl group; or the ring A may be taken with the pyridyl group binding to the ring A to form a ring; the alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, alkoxy group, alkylthio group, acyl group, and alkyloxycarbonyl group represented by R²⁰⁶, R²⁰⁷, R²⁰⁸, and R²⁰⁹ may be

substituted; or R and R or R and R are a group of formula

or

, wherein A^41', A^42', A^43', A^44', A^45', and A^46' are independently of each other H, halogen, CN, Ci-C₂₄alkyl, Ci-C₂₄perfluoroalkyl, Ci-C₂₄alkoxy, Ci-C₂₄alkylthio, C₆-Ci₈aryl, which may optionally be substituted by G, -NR³¹⁰R³¹¹, -CONR³¹⁰R³¹¹, or -

COOR , or C₂-Cioheteroaryl; especially , or , wherein

R and R are independently of each other C₆-Ci₈aryl, C₇-Ci₈aralkyl, or Ci-C₂₄alkyl,

R ^■«3^J1^l2^z is Ci-C₂₄alkyl, C₆-Ci₈aryl, or C₇-Ci₈aralkyl;

G is Ci-Ci₈alkyl, -OR^JUb, -SR^JUb, -NR^JUbR^JUb, -CONR^JUbR^JUb, or -CN, wherein R^JUb and

R ->306 are independently of each other C₆-Ci₈aryl; C₆-Ci₈aryl which is substituted by d- Ci₈alkyl, or Ci-Ci₈alkoxy; Ci-Ci₈alkyl, or Ci-Ci₈alkyl which is interrupted by -O-; or L is a bidentate ligand L' selected from

R¹¹ and R¹⁵ are independently of each other hydrogen, CrC₈alkyl, C₆-Ci₈aryl, C₂- Cioheteroaryl, or Ci-C₈perfluoroalkyl,

R¹² and R¹⁶ are independently of each other hydrogen, C₆-Ci₈aryl, or d-C₈alkyl, and R¹³ and R¹⁷ are independently of each other hydrogen, d-C₈alkyl, C₆-Ci₈aryl, C₂- Cioheteroaryl, Ci-C₈perfluoroalkyl, or Ci-C₈alkoxy, and R¹⁴ is Ci-C₈alkyl, C₆-Ci₀aryl, or C₇-Cnaralkyl,

R¹⁹ is Ci-C₈alkyl, or C_rC₈perfluoroalkyl, R²⁰ is hydrogen, Ci-C₈alkyl, or C₆-Ci₀aryl,

R²¹ is hydrogen, Ci-C₈alkyl, or Ci-C₈alkoxy, which may be partially or fully fluorinated, R²² and R²³ are independently of each other C_q(H+F)_2q+1, or C₆(H+F)_5, R²⁴ can be the same or different at each occurrence and is selected from H, or C_q(H+F)_2q+1, R⁴⁶ is Ci-C₈alkyl, C₆-Ci₈aryl, or C₆-Ci₈aryl, which is substituted by Ci-C₈alkyl, q is an integer of 1 to 24, p is 2, or 3, or L is a bidentate ligand L" selected from

(X-1 ). (X-2), (X-3), (X-4), (X-5),

(X-7), (X-8), (X-9), (X-10),

4),

(X-35),

(X-36),

37),

(X-37), (X-38), (X-39), (X-

(X-55), (X-56), or (X-57).

8. The metal complex according to claim 6, wherein the metal complex is represented by formula formula

(Ha), or (Mb), wherein m is 1 , n is 2, M is Ir,

, R^Λ, R\ R^, FT, R⁴⁴ and R^4b are as defined in claim 5 and R¹¹, R¹² and R¹³ are as defined in claim 7.

9. The metal complex according to claim 8 of formula:

10. An organic electronic device, comprising an emitting layer wherein the emitting layer comprises a compound according to any of claims 1 to 9.

1 1. The device of claim 10, further comprising a hole transport layer selected from polyvinyl-carbazol, N, N'-diphenyl-N, N'-bis(3-methylphenyl)-[1 ,1 '-biphenyl]-4,4'-diamine (TPD), 1 ,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC), N,N'-bis(4-methylphenyl)- N,N'-bis(4-ethylphenyl)-[1 ,1 '-(3,3'-dimethyl)biphenyl]4,4'-diamine (ETPD), tetrakis-(3- methylphenyl)-N,N,N',N'-2,5-phenylenediamine (PDA), a-phenyl-4-N,N- diphenylaminostyrene (TPS), p-(diethylamino)benzaldehydediphenylhydrazone (DEH), triphenylamine (TPA), bis[4-(N,N-diethylamino)-2-methylphenyl](4- methylphenyl)methane (MPMP), 1-phenyl-3-[p-(diethylamino)styryl]-5-[p- (diethylamino)phenyl]pyrazoline (PPR or DEASP), 1 ,2-trans-bis (9H-carbazol-9- yl)cyclobutane (DCZB), N,N,N',N'-tetrakis (4-methylphenyl)-(1 ,1'-biphenyl)-4,4'-diamine

(TTB), N,N'-di-α-naphthyl-N,N'-diphenyl-4,4'-diphenyldiamine (α-NPD), porphyrinic compounds, and combinations thereof, or electrontransporting materials, such as tris(8- hydroxyquinolato)aluminium (Alq3), bis(2-methyl-8-hydroxyquinaolato)(p- phenylphenolato)aluminium(BAIq), tetrakis(8-hydroxyquinolato)zirconium(ZrQ) and mixtures thereof.

12. The device according to claims 10, or 1 1 , which is an electro photographic photoreceptor, a photoelectric converter, a solar cell, an image sensor, a dye laser, or an organic transistor.

13. Use of a compound according to any of claims 1 to 9 in electronic devices, especially organic light emitting diodes (OLEDs), electro photographic photoreceptors, photoelectric converters, solar cells, image sensors, dye lasers, organic transistors, as oxygen sensitive indicators, as phosphorescent indicators in bioassays, or catalysts.

14. Compounds of formula

, wherein X is H, methyl, or ethyl,

and L^a is

, wherein Q¹ , Y¹ , Y², Y³, Y⁴, X¹ , X² and X³ are as defined in claim

1.

15. A method for preparing iridium metal complexes of formula lr(L^a)₃, wherein L^a is

, which comprises reacting iridium trichloride hydrate with an excess of L^aH in the presence of 3 equivalents silver trifluoroacetate and optionally in the presence of a solvent, wherein Q¹, Y¹, Y², Y³, Y⁴, X¹, X² and X³ are as defined in claim 1.