Method for preparing bischloroformate compositions

摘要

Bischloroformate compositions are prepared by passing gaseous phosgene into an agitated aqueous solution of a di-(alkali metal) salt of an organic dihydroxy compound such as bisphenol A, while maintaining said solution at a temperature within the range of about 0 DEG -50 DEG C. Phosgene passage and agitation are continued until the bischloroformate composition has precipitated. The reaction is typically complete when the pH of the aqueous phase drops below 7.