Process for the preparation of benzophenthiones and benzophenones
AssigneeZeneca Limited
InventorsMichael Charles Henry Standen, Nicholas Charles Evens
Life of this patent
Estimating the term…
Abstract
A process comprising the reaction of an optionally substituted benzene with thiophosgene in the presence of a Friedel Crafts catalyst for the preparation of the equivalent optionally substituted benzophenthione. The benzophenthiones are converted into the equivalent benzophenone derivatives by hydrolysis.
Claims8
A process for the preparation of an optionally substituted benzophenone which comprises reacting the equivalently substituted benzophenthione with an aqueous solution of HCl in methanol.
A process for the preparation of an optionally substituted benzophenone which comprises reacting the equivalently substituted benzophenthione with an aqueous solution comprising a mixture of HCl and CH.sub.3 COOH.
A process for the preparation of a di-halosubstituted benzophenone which comprises reacting a benzene mono-substituted with a halogen, with thiophosgene in the presence of a Friedel-Craft's catalyst, and reacting the di-halosubstituted benzophenthione so produced with an aqueous solution of HCl in methanol.
Dependencies are inferred from the claim text.