Chlorodimethylsilane-Mediated Reductive Etherification Reaction: A Robust Method for Polyether Synthesis

Abstract

Polyethers have always been privileged compounds in polymer chemistry and have found extensive applications in both academic research and industry. However, the currently employed strategies for their synthesis require harsh conditions such as ionic polymerizations together with limited precursor monomer options. In this study, a chlorodimethylsilane (CDMS)-mediated reductive etherification reaction was introduced as a versatile strategy for polyether synthesis. Accordingly, terephthalaldehyde (TPA) and 1,4-butanediol were first reacted at room temperature in the presence of CDMS using nitromethane as the polymerization solvent to reveal the optimum conditions for the proposed system. Subsequently, a variety of diols ranging from linear to sterically congested diols were reacted with TPA (and its isomers) under the optimized conditions to create a polyether library. Meanwhile, in addition to polyether having the expected alternating units, the formation of polyether stem from the self-condensation of TPA was found to be inevitable in all cases. From the proposed strategy, polyethers with a molecular weight of up to 110.4 kDa and a high alternating unit of up to 93% were obtained. The versatile and robust character of the presented strategy was supported by a model end-group study, and the polymerization behavior was examined mechanistically. It is anticipated that the presented method might be a strong candidate for polyether synthesis with different backbones, given the unlimited sources of diols.