Method for producing camphorsultam
AssigneesSumika Fine Chemicals Co., Ltd., Ono Pharmaceuticals Co., Ltd.
InventorsHiroshi Shiratani, Shigeya Yamasaki
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Abstract
A method for producing camphorsultam, which includes the following steps 1 to 4: Step 1: reacting camphorsulfonic acid with a halogenation agent to give camphorsulfonyl halide, Step 2: reacting the camphorsulfonyl halide with ammonia to give camphorsulfonamide, Step 3: subjecting the camphorsulfonamide to dehydration and ring closure to give camphorsulfonimine, and Step 4: reducing the camphorsulfonimine with sodium borohydride in an aqueous isopropanol solution. According to this invention, camphorsultam and intermediates thereof can be obtained by an industrial method which is comparatively safe to the environment and human body, economical, and which is simple and easy.
Claims12
A method for producing camphorsultam, which comprises the steps of:
- Step 1:
- reacting camphorsulfonic acid with thionyl chloride in toluene to give camphorsulfonyl halide,
- Step 2:
- reacting the camphorsulfonyl halide with ammonia to give camphorsulfonamide,
- Step 3:
- subjecting the camphorsulfonamide to dehydration and ring closure to give camphorsulfonimine, and
- Step 4:
- reducing the camphorsulfonimine with sodium borohydride in an aqueous isopropanol solution.
Dependencies are inferred from the claim text.