Anionic synthesis of omega-dimethylamino-functionalized polymers by functionalization of polymeric organolithiums with 3-dimethylaminopropyl chloride

The functionalization reactions of polystyryllithium, polyisoprenyllithium and polybutadienyllithium in benzene with 3-dimethylaminopropyl chloride ha ve been investigated in detail. The effects of addition mode (normal and in verse addition), added Lewis bases (THF and TMEDA), temperature and concent ration have been investigated. The polymer products were analysed by SEC, H -1 and C-13 NMR spectroscopy and end-group titration. The pure omega-dimeth ylamino-functionalized polymers were quantitatively isolated by silica gel column chromatography. The functionalizations of polystyryllithium, polyiso prenyllithium and polybutadienyllithium by normal addition in benzene produ ce the corresponding omega-dimethylamino-functionalized polymers in isolate d yields of 67%, 85% and 90%,respectively. Functionalization efficiencies w ere improved by using the inverse addition procedure and by post-polymeriza tion addition of Lewis bases before functionalization. (C) 1999 Society of Chemical Industry.