NEW SYNTHESIS OF POLY(S-THIOESTER)S BY REGIOSELECTIVE ADDITION-REACTION OF BIS(THIIRANE)S WITH DIACYL CHLORIDES USING QUATERNARY ONIUM SALTS

Poly(S-thioester)s were successfully synthesized by a new addition rea ction of bis(thiirane)s with diacyl chlorides catalyzed by quaternary onium salts or crown ether complexes. The polyaddition of Bisphenol A bis(2,3-epithiopropyl) ether (BPTE) or butanediol bis(2,3-epithiopropy l) ether with certain diacyl chlorides proceeded smoothly using quater nary onium chlorides to give the corresponding poly(S-thioester)s with relatively high molecular weights. When the reaction of BPTE with ter ephthaloyl chloride or isophthaloyl chloride was carried out using 5 m ol % of tetrabutylammonium chloride (TBAC) or tetrabutylphosphonium ch loride (TBPC) in anisole at 90 degrees C for 24 h, the poly(S-thioeste r) with a number-average molecular weight of 40 000 was obtained. The reaction was enhanced more efficiently in aromatic solvents such as to luene or anisole than in aprotic polar solvents. It was proven that th e reaction proceeded regioselectively to give the poly(S-thioester)s w ith the pendant chloromethyl group, which was introduced simultaneousl y with the formation of a S-thioester linkage in the polymer backbone during the reaction.