Patent ID: 8304542

Claim:
A compound of the formula (1) M(L) n (L′) m (L″) o Formula (1) wherein substructure M(L) n of formula (1) is of the formula (2) wherein M is a transition metal; D identically or differently on each occurrence is an sp 2 -hybridized heteroatom having a nonbonding electron pair coordinated to M; C is an sp 2 -hybridized carbon atom bound to M; E identically or differently on each occurrence is an sp 2 -hybridized carbon or nitrogen atom; Z identically or differently on each occurrence is C(R) 2 or NR; Cy1 identically or differently on each occurrence is a homocycle or heterocycle bound to M via an sp 2 -hybridized carbon atom and is optionally bonded to R; Cy2 identically or differently on each occurrence is a heterocycle coordinated to M via D and is optionally bonded to R; R identically or differently on each occurrence is H; F; CN; a straight-chain alkyl or straight-chain alkoxy group having up to 40 carbon atoms; or a branched or cyclic alkyl or branched or cyclic alkoxy group having from 3 to 40 carbon atoms; wherein one or more nonadjacent CH 2 groups in said straight-chain alkyl, straight-chain alkoxy, branched or cyclic alkyl, or branched or cyclic alkoxy groups is optionally replaced by —R 2 C═CR 2 —, —C≡C—, Si(R 2 ) 2 , Ge(R 2 ) 2 , Sn(R 2 ) 2 , —O—, —S—, —NR 2 —, —(C═O)—, —(C═NR 2 )—, —P═O(R 2 )—, SO, SO 2 , or —CONR 2 —; and wherein one or more H atoms is optionally replaced by F, an aromatic or heteroaromatic ring system having from 5 to 40 aromatic ring atoms, or an aryloxy or heteroaryloxy group having from 5 to 40 aromatic ring atoms, wherein said aromatic or heteroaromatic ring system, or aryloxy or heteroaryloxy group is optionally substituted by one or more nonaromatic radicals R; or a combination of two, three or four of these systems; and wherein R together with Cy1 and/or Cy2 optionally define an aliphatic, aromatic, or heteroaromatic ring system; R 2 identically or differently on each occurrence is H or an aliphatic or aromatic hydrocarbon radical having up to 20 carbon atoms; n is 1, 2 or 3; and wherein L′ and L″ are monoanionic, bidentate chelating ligands; m and o identically or differently on each occurrence are 0, 1 or 2; and the sum of n, m, and o is 2 or 3.