Materials for organic electroluminescent devices

1. A compound of the general formula I

or of the general formula II

wherein

M is a metal ion in oxidation state +2,

Ar, is, identically or differently on each occurrence, an aromatic or heteroaromatic ring system having 5 to 10 aromatic ring atoms, which is optionally substituted by a plurality of radicals R,

R is, identically or differently on each occurrence, H, D, F, Cl, Br, I, N(Ar 1 ) 2 , N(R 2 ) 2 , CN, NO 2 , Si(R 2 ) 3 , B(OR 2 ) 2 , C(═O)Ar 1 , C(═O)R 2 , P(═O)(Ar 1 ) 2 , P(═O)(R 2 ) 2 , S(═O)Ar 1 , S(═O)R 2 , S(═O) 2 Ar 1 , S(═O) 2 R 2 , CR 2 ═CR 2 Ar 1 OSO 2 R 2 , a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 C atoms, each of which is optionally substituted by one or more radicals R 2 , where one or more non-adjacent CH 2 groups is optionally replaced by R 2 C═CR 2 , C═O, O, or S and where one or more H atoms is optionally replaced by D, F, Cl, Br, I, CN or NO 2 , or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R 2 , or an aryloxy or heteroaryloxy group having 5 to 15 aromatic ring atoms, which is optionally substituted by one or more radicals R 2 , or a combination of these systems, where two or more substituents R optionally forms a mono- or polycyclic, aliphatic or aromatic ring system with one another,

Ar 1 is, identically or differently on each occurrence, an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which is optionally substituted by one or more non-aromatic radicals R,

Y is, identically or differently on each occurrence, C, N or P, with the proviso that either two C atoms and two N atoms or two C atoms and two P atoms are always bonded to the metal, and

R 1 is, identically or differently on each occurrence, H, D, F, CF 3 , CN, an alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 C atoms, each of which is optionally substituted by one or more radicals R 2 , where one or more non-adjacent CH 2 groups is optionally replaced by R 2 C═CR 2 , C≡C, Si(R 2 ) 2 , Ge(R 2 ) 2 , Sn(R 2 ) 2 and where one or more H atoms is optionally replaced by D, F, Cl, Br, I, CN or NO 2 , or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R 2 , or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R 2 , or a combination of these systems, where R 1 may also form a mono- or polycyclic, aliphatic or aromatic ring system with R, and

R 2 is, identically or differently on each occurrence, H, D, F, CN or an aliphatic, aromatic and/or heteroaromatic hydrocarbon radical having 1 to 20 C atoms, in which, in addition, one or more H atoms is optionally replaced by F, where two or more substituents R 2 also form a mono- or polycyclic, aliphatic or aromatic ring system with one another.

2. The compound according to claim 1 , wherein M is Pt or Pd.

3. The compound according to claim 1 , wherein M is Pt.

4. The compound according to claim 1 , wherein

M is Pt,

Y is, identically or differently on each occurrence, C or N, with the proviso that two C atoms and two N atoms are always bonded to the metal,

R is, identically or differently on each occurrence, H, N(Ar 1 ) 2 , CN, a straight-chain alkyl group having 1 to 10 C atoms or an aromatic or heteroaromatic ring system having 5 to 15 aromatic ring atoms, each of which is optionally substituted by one or more radicals R 2 ,

R 1 is, identically or differently on each occurrence, H, D, CN, an alkyl group having 1 to 3 C atoms or an aromatic or heteroaromatic ring system having 5 to 10 aromatic ring atoms, each of which is optionally substituted by one or more radicals R 2 ,

R 2 is, identically or differently on each occurrence, H, F, CN or an aliphatic, aromatic and/or heteroaromatic hydrocarbon radical having 1 to 20 C atoms, where two or more substituents R 2 may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another, and

Ar 1 is, identically or differently on each occurrence, an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which is optionally substituted by one or more non-aromatic radicals R.

5. The compound according to claim 1 , wherein Ar is benzene, naphthalene, pyridine, pyrimidine, pyrazine, pyridazine, quinoline, isoquinoline, furan, thiophene, pyrrole, benzofuran, benzothiophene or indole.

6. The compound according to claim 1 , wherein Ar is benzene, naphthalene, pyridine, quinoline or isoquinoline.

7. The compound according to claim 1 , wherein the compound is of the formulae V to XVI:

8. A oligomer, polymer or dendrimer comprising one or more compounds according to claim 1 , where one or more bonds are present from the compounds of the formula I or II to the polymer, oligomer or dendrimer.

9. A process for the preparation of the compound according to claim 1 , which comprises reacting a free ligand with a corresponding metal salt to give the complex.

10. A layer comprising one or more of the compounds according to claim 1 .

11. The compound according to claim 1 , wherein the compound is of the formula III or IV:

wherein

X is CR or N.

12. The compound according to claim 11 , wherein a maximum of two symbols X per ring stand for N and the other symbols X in this ring stand for CR.

13. An electronic device comprising one or more compounds according to claim 1 .

14. The electronic device as claimed in claim 13 , wherein the electronic device is an organic electroluminescent device or polymeric electroluminescent device (OLED, PLED), an organic integrated circuit (O-IC), an organic field-effect transistor (O-FET), an organic thin-film transistor (O-TFT), an organic light-emitting transistor (O-LET), an organic solar cell (O-SC), an organic optical detector, an organic photoreceptor, an organic field-quench device (O-FQD), a light-emitting electrochemical cell (LEC) or an organic laser diods (O-laser).

15. An organic electroluminescent device according to claim 14 , wherein the compound is employed as emitting compound in an emitting layer or as charge-transport compound in a charge-transport or charge-injection layer.