Efficient Post-Polymerization modification of pendant aldehyde functional polymer via reductive etherification reaction

Abstract

The aldehydes have always been a privilege in polymer science since the aldehyde carbonyl readily undergoes several reactions efficiently under mild conditions, ranging from non-aldol reactions to multicomponent reactions, mostly without any additive. In the current study, the versatility of the aldehyde group has been further exploited using the reductive etherification reaction (RER), which has proven to be a useful synthetic strategy to convert aldehyde or ketone carbonyls to ethers in the presence of organosilane compounds. For this purpose, a polymer platform containing pendant aldehyde units was synthesized via free radical polymerization (FRP) and modified with a variety of alcohols using chlorodimethylsilane (CDMS) as the reducing agent. The spectroscopic analyses indicated that pendant aldehydes successfully turned to corresponding ethers with quantitative or near quantitative RER efficiencies. The proposed strategy was also extended to thiols and the resultant polymers were found to be in thioacetal and/or thioether pendant forms. Given the growing demand for the development of new synthetic methodologies that can be adapted to the macromolecular level, a new insight into the modification of aldehyde-functionalized polymers has been introduced in this study.