Process for producing preparing sulfonyl ethers from sulfonic acids

摘要

A method of preparing a sulfonyl ether comprising the steps of:

i) reacting a sulfonic acid with an anhydride, under continuous vacuum distillation conditions, to form a carboxysulfonate;

ii) reacting the carboxysulfonate with an optionally substituted cycloalkane ring containing at least 3 heteroatoms to form a sulfonyl ether pre-mix comprising a sulfonyl ether and at least two additional reaction products each containing at least one ether linkage;

iii) subjecting the pre-mix to continuous vacuum distillation conditions to remove at least some of the additional reaction products from the sulfonyl ether pre-mix to provide a crude sulfonyl ether product; and

iv) purifying the crude sulfonyl ether product. The preferred sulfonic acid is a methanesulfonic acid and the preferred sulfonyl ether is bis(methanesulfonylmethyl)ether (BSME). The preferred carboxysulfonate is acetyl methane sulfonate (AMS). The preferred cycloalkane comprising three hetero atoms is trioxane.