Sodium Sulfite → 1,2-Benzisoxazole-3-methanesulfonate sodium

Participants

Reaction Steps

A process for the preparation of zonisamide, disclosed in U.S. Pat. No. 4,172,896, comprises the sulfonation of 3-bromomethyl-benzo[d]isoxazole (1) with sodium sulfite to obtain benzo[d]isoxazol-3-yl-methanesulfonic acid sodium salt (2) which is then transformed into the corresponding sulfonyl chloride (3) by treatment with phosphorous oxychloride. The reaction of the latter with gas ammonia yields zonisamide (4), as reported hereinbelow.

Provenance & Evidence