Selective polymerization of epoxides from hydroxycarboxylic esters: expediting controlled synthesis of α-carboxyl-ω-hydroxyl polyethers.

Selective ring-opening polymerization of ethylene/propylene oxide from hydroxyl-functionalized carboxylic esters is achieved by use of metal-free Lewis pair catalysts. Subsequently, quantitative in situ hydrolysis is conducted to afford well-defined α-carboxyl-ω-hydroxyl polyethers which are highly valuable for bioconjugation but usually synthesized by much more tedious and costly routes.