反应详情

To a solution of tert-butyl 4-hydroxypiperidine-1-carboxylate (1B2) (464 mg, 2.3 mmol) in dioxane (10 mL) at room temperature was added NaH (114 mg, 2.8 mmol). The mixture was stirred for 20 min and 5-bromo-4-nitroisothiazole (P) (400 mg, 1.9 mmol) was added. The mixture was stirred at 65° C. for 5 hours, cooled to room temperature, diluted with ethyl acetate (100 mL), washed with brine, dried over Na2SO4, and concentrated in vacuo at room temperature (25° C.). The residue was purified with flash column (eluent: 10-30% ethyl acetate/petroleum ether) to afford the product tert-butyl 4-(4-nitroisothiazol-5-yloxy)piperidine-1-carboxylate (1C3) (280 mg, 0.85 mmol).

1. stirringThe mixture was stirred at 65° C. for 5 hours
2. washwashed with brine
3. dry with materialdried over Na2SO4
4. concentrationconcentrated in vacuo at room temperature (25° C.)
5. customThe residue was purified with flash column (eluent: 10-30% ethyl acetate/petroleum ether)