Patent ID: 8883325

Claim:
A composition comprising a compound of the formula wherein R 1 is a 1-5 ring aryl, aralkyl or heteroaryl group which is optionally substituted with one or more C 1 -C 4 alkyl, alkoxy or cyano; R 2 and R 3 together form a 1-5 ring aryl, aralkyl or heteroaryl group which is optionally substituted with C 1 -C 4 alkyl, alkoxy or cyano; R 4 is hydrogen, C 1 -C 4 alkyl or aryl; and Ar is monocyclic, bicyclic or tricyclic aryl or heteroaryl which is optionally substituted with one or more C 1 -C 4 -alkyl or alkoxy groups and another organic semiconductor material or a metal.