Synthesis of polyesters with pendant chloromethyl group by polyaddition of bis(oxetane)s with diacyl chlorides catalyzed by quaternary onium salts

A new polyaddition of bis(oxetare)s with diacyl chlorides catalyzed by quaternary onium salts is described. The reactions of the new bifunctional monomer, bis(3-methyl-3-oxetanylmethyl) terephthalate, with terephthaloyl chloride using quaternary ammonium halides proceed smoothly under mild conditions to give the corresponding polyester with chloromethyl group in the side chain. It was proved that quaternary onium halides such as tetraethylammonium bromide and tetrabutylammonium chloride and bromide (TBAB) had high catalytic activity in the polymerization in low polar solvents such as anisole and toluene to produce the polyester with high molecular weight. The polyaddition of various bis(oxetane)s with diacyl chlorides using TBAB as the catalyst also proceeded to give the targeted polyesters with pendant chloromethyl group, which is introduced simultaneously with the formation of the polymer backbone during the reaction.