Quantitative omega-amination, omega-azidolysis, and omega-thiolation of poly(ethylene oxide)s through anionic mechanism

Abstract

n-Butyllithium-initiated ring-opening polymerization of ethylene oxide with potassium t-butoxide in the mixture of benzene and dimethyl sulfoxide (DMSO) at 35 A degrees C yielded corresponding "living" polymeric alkoxide. The molecular weight was well controlled on the basis of stoichiometric balance. Quantitative chain-end functionalizations, such as the amination, the azidation, and the thiolation of polymeric alkoxide, were performed. The yields were almost quantitative (over 98 mol%). The resulting products were characterized by the combination of H-1 NMR spectroscopy, UV/Visible spectroscopy, FTIR, MALDI-TOF MS analysis, and size exclusion chromatographic analysis.