Patent ID: 6107496
Filing Date: 2000-08-22
Classification: C07D,Y02P

Abstract:
A process for the preparation of cyclic esters of the general formula: ##STR4## in which m is an integer from about 6 to about 14 and n is an integer from about 2 to about 6, which comprises reacting:(a) a dicarboxylic acid bis(glycol) ester of the general formula:HO--(CH.sub.2).sub.n --O--CO--(CH.sub.2).sub.m --CO--O--(CH.sub.2).sub.n --OH, (II)in which m and n are as defined above,(b) optionally, up to 100% by weight, based on that of the ester II, of at least one ester of the general formula:H[O--(CH2).sub.n --O--CO--(CH.sub.2).sub.m --CO--].sub.x --O--(CH.sub.2).sub.n --OH, (III)H[O--(CH.sub.2).sub.n --O--CO--(CH.sub.2)m--CO--]X--OH, and(IV)HO--CO--(CH.sub.2).sub.m --CO--[--O--(CH.sub.2).sub.n O--CO--(CH.sub.2).sub.m --CO--].sub.x --OH, (V)in which m and n are as defined previously and x is an integer >1,(c) a glycol of the general formula:HO--(CH.sub.2).sub.n --OH, (VI)in which n has the same numerical value as in formula I-V, present in a molar amount of from about 1 to about 50 times the total molar amounts of ester II and dicarboxylic acid units of esters III-V, and(d) an inert high-boiling reaction medium present in an amount of from about 0.1 to about 20 times the total weight of esters II-V, in the presence of(e) a catalyst.