Patent ID: 6951694

Claim:
An organic light emitting device, comprising an electron blocking layer disposed adjacent to an emissive layer, wherein the electron blocking layer comprises a compound of the formula I wherein M is a metal; each A 1 and A 2 is, independently, a monodentate ligand; or A 1 and A 2 are covalently joined together to form a bidentate ligand; each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , and R 7 is, independently, H, alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3 , C x F 2x+1 , trifluorovinyl, CO 2 R, C(O)R, NR 2 , NO 2 , OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl or a heterocyclic group, and additionally, or alternatively, any one or more of R 1 and R 2 , or R 2 and R 3 , or R 3 and R 4 , or R 4 and R 5 , or R 5 and R 6 , or R 6 and R 7 together form, independently, a fused 5- to 6-member cyclic group, wherein said cyclic group is cycloalkyl, cycloheteroalkyl, aryl, or heteroaryl, and wherein the fused 5- to 6-member cyclic group may be optionally substituted with one or more of alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3 , C x F 2x+1 , trifluorovinyl, CO 2 R, C(O)R, NR 2 , NO 2 , OR, halo; each R is independently H, alkyl, alkenyl, alkynyl, alkylaryl, and aryl; m is 1, 2, or 3; and n is 0, 1, or 2, wherein m+n equals 3.