Synthesis of novel polysiloxanes containing charge transporting and second-order nonlinear optical functionalities with atom economical constructs

摘要

Novel, highly functionalized polysiloxanes were prepared in which each repeat unit bears, on average, one charge transporting and one to two second-order nonlinear optical chromophores. Covalent attachment of charge-transporting carbazole or diphenylamine derivatives was realized through efficient Pt-catalyzed hydrosilylation. Poly(hydrogen methylsiloxane) was reacted with 9-(2-propenyl)carbazole or (N-phenyl-N-2-propenylamino)benzene, affording poly[methyl-3-(9-carbazolyl)propylsiloxane] and poly[methyl-3-(N,N-diphenylamino)propylsiloxane], respectively. Rather remarkable regiospecific bromination of the two arylamine-containing siloxane polymers was achieved using benzyltrimethyl ammonium chlorobromate, resulting in the formation of poly[methyl-3-(N-(3,6-dibromocarbazolyl))propylsiloxane] and poly[methyl-3-(N,N-bis(4-bromophenyl)amino)propylsiloxane]. Pd-catalyzed Heck-type coupling of the arylbromide-bearing polysiloxanes with either vinylbenzenephosphonic acid diethyl ester or 4-nitrostyrene afforded stilbene-containing polymers bearing phosphonate ester or nitro moieties as electron-withdrawing functionalities, respectively. These fully functionalized polymers were readily soluble in several common organic solvents. [References: 52]