Preparation of N, N, N′N′- Tetraphenylbiphenyldiamines for Organic Electroluminescent Device as Hole Transport Materials

The tetraphenylbiphenyldiamines used as the hole transport materials have great application potentiality in organic electroluminescent(OEL) devices. Three of these compounds were prepared by Ulmann reaction .They were N, N′ diphenyl N, N′ bis(3 methylphenyl) [1, 1′ biphenyl] 4, 4′ diamine(1) , N, N′ diphenyl N, N′ bis(4 methylphenyl) [1, 1′ biphenyl] 4, 4′ diamine(2) and N, N, N′, N′ tetraphenyl [1, 1′ biphenyl] 4, 4′ diamine(3). The method of seperating products from the reaction mixtures was improved, and the yields and purities are (1)Y 85%,P97.6% ;(2)Y95%, P 98.5% and (3)Y 70%, 98.1%, respectively. Their IR spectra were all measured also.