反应详情

0.9 g (2.5 mmol) of 2-chloro-4-ethylsulfonyl-3-(3a,4,5,6a-tetrahydrofuro[3,2-d]-isoxazol-3yl)benzoic acid together with 0.31 g (2.8 mmol) of 1,3-cyclohexandione in 50 ml of dichloromethane are treated with 0.53 g (2.8 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimi hydrochloride and 0.1 g of N,N-dimethylaminopyridine. After the mixture has been stirred for 16 hours at room temperature, it is washed with 1 N hydrochloric acid and sodium chloride solution and dried over magnesium sulfate. It is filtered with suction and the filtrate is concentrated. This gives 0.66 g (58% of theory) of crude 3-oxocyclohex-1-enyl 2-chloro-4-ethylsulfonyl-3-(3a ,4,5,6a-tetrahydrofurro[3,2-d]isoxazol-3-yl)benzoate.

1. washit is washed with 1 N hydrochloric acid and sodium chloride solution
2. dry with materialdried over magnesium sulfate
3. filtrationIt is filtered with suction
4. concentrationthe filtrate is concentrated