SYNTHESIS OF A BIS (SULFONYL) ETHER FROM SULFONIC ACID VIA THE CORRESPONDING CARBOXYSULFONATE

摘要

The present invention provides a method of preparing a sulfonyl ether com prising the steps of: v) reacting a sulfonic acid with an anhydride, under c ontinuous vacuum distillation conditions, to form a carboxysulfonate; vi) re acting the carboxysulfonate with an optionally substituted cycloalkane ring containing at least 3 heteroatoms to form a sulfonyl ether pre-mix comprisin g a sulfonyl ether and at least two additional reaction products each contai ning at least one ether linkage; vii) subjecting the pre-mix to continuous v acuum distillation conditions to remove at least some of the additional reac tion products from the sulfonyl ether pre-mix to provide a crude sulfonyl et her product; and viii) purifying the crude sulfonyl ether product.