Organocatalytic Living Ring-Opening Polymerization of Cyclic Carbosiloxanes
作者： Bas GG Lohmeijer , Geraud Dubois , Frank Leibfarth , Russell C Pratt , Fredrik Nederberg
DOI: 10.1021/OL0614166
关键词:
摘要: An organocatalytic route to narrowly dispersed poly(carbosiloxanes) of predictable molecular weight and end group fidelity is described. N-Heterocyclic carbenes (NHC) 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) catalyze the ring opening cyclic carbosiloxanes. The pKb catalyst important in preventing adverse transetherification reactions obtaining well-defined polymers. Mechanistic studies indicate that hydrogen bonding TBD or NHC activates alcohols silanols for ring-opening reactions.
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