反应详情

1.0 Gram (4.0 mmol) of the 4-methoxyimino-5-methylthiochroman-6-carboxylic acid obtained in the above (2) was reacted with 1.3 g (12 mmol) of a 30% hydrogen peroxide aqueous solution in 5 ml of acetic acid at 100° C. for 1 hour. Ethyl acetate was added to the reaction product, and the mixture was washed with a saturated sodium chloride aqueous solution and then dried over sodium sulfate. The solvent was distilled off to give 1.1 g (yield 97%) of 4-methoxyimino-5-methylthiochroman-6-carboxylic acid-1,1-dioxide.

1. washthe mixture was washed with a saturated sodium chloride aqueous solution
2. dry with materialdried over sodium sulfate
3. distillationThe solvent was distilled off