Preparation of high purity di-lower alkyl naphthalenedisulfonates

摘要

Disclosed is an improved process for preparing di-lower alkyl naphthalenedisulfonyl by employing a naphthalenedisulfonate chloride and a stoichiometrically excess amount of an aliphatic alcohol and allowing them to react in the presence of an aqueous solution of an alkali. The improved process comprises treating the reaction product from said process with an alkali metal alcoholate and then washing the thus treated reaction product with water to obtain a highly pure product. Also disclosed is a process of limiting the formation of undesirable impurities arising from the reaction of said naphthalenedisulfonyl chloride and said aliphatic alcohol.