Room-temperature polycondensation of dicarboxylic acids and diols catalyzed by water-stable lewis acids

Abstract

Room-temperature polycondensations of methylsuccinic acid (MSA) (at 35°C), bromosuccinic acid (BSA), 2-bromoadipic acid (BAA) (at 40°C), and citraconic acid (CA) (at 60°C) with diols containing 1,3-propanediol (1,3-PD) and 1,4-butanediol (1,4-BD) were performed under reduced pressure (0.3-30 mmHg) using scandium trifluoromethanesulfonate [Sc(OTf)3], scandium trifluoromethanesulfonimide [Sc(NTf2)3], and polymer-supported scandium trifluoromethanesulfonate (PS-Sc) to give poly(alkylene succinate)s with Mn = 0.67×104 - 1.41×104 (Mw/Mn=1.4-2.1) with quantitative yields. The catalysts are recovered quantitatively and reused. Room-temperature polycondensation made it possible to use thermally unstable monomers containing carbon-carbon double bond and bromo functionalities. Atom-transfer radical polymerization (ATRP) of methyl methacrylate (MMA) using poly(butylene succinate-co-butylene 2-bromoadipate) [poly(BS-co-BBA)] as the macroinitiator and complex of CuBr and 1,1,4,7,10,10- hexamethyltriethylenetetramine (HMTETA) as the catalyst was carried out to give polyester having PMMA side chains [Mn = 2.01×104, 65 % yield].