Stereospecific Anionic Polymerization and Novel Hydrogen-Transfer Polymerization of α-(Aminomethyl)acrylates Having Unprotected Amino Group

Abstract

Anionic polymerization of α-(aminomethyl)acrylates (2—8) having an unprotected amino proton was carried out using lithium reagents at −78°C. Acrylates except for 4 and 8 afforded the polymers in good yields. The polymerization of ethyl α-[N-(diphenylmethyl)aminomethyl]acrylate (3) with n-BuLi or the Ph2NLi-N,N,N′,N′-tetramethylethylene-diamine (TMEDA) complex in toluene afforded a polymer with a normal vinyl polymer structure and high isotacticity. Hydrogen-transfer of the amino proton hardly occurred in the polymerization process. The anionic polymerizations of ethyl α-[N-(1-phenylethyl)aminomethyl]acrylate (2) using lithium reagents in toluene and tetrahydrofuran (THF) proceeded with hydrogen-transfer reaction. CH carbon generated by hydrogen-transfer in the main chain was detected by DEPT NMR measurement of poly(2). The CH-containing unit in the polymer increased up to nearly 40% when THF was used as a solvent. Monomers 4 and 8 showed low polymerizability.