反应详情

温度

55 °C

To a solution of methanesulfonic acid 2-((R)-4-benzyloxycarbonylamino-4,5,6,7-tetrahydroindazol-1-yl)-ethyl ester (850 mg, 2.16 mmol) in dimethyl sulfoxide (20 mL) was added sodium cyanide (540 mg, 10.8 mmol). The mixture was stirred at 55° C. for 4 hours. After cooling, to the mixture was added water, and the aqueous layer was extracted with ethyl acetate (20 mL×4). The combined organic layers were dried over sodium sulfate, filtered and then concentrated in vacuo. The residue was purified by flash column chromatography (10% methanol in dichloromethane) to afford (R)-[1-(2-cyano-ethyl)-4,5,6,7-tetrahydro-1H-indazol-4-yl]-carbamic acid benzyl ester (600 mg, 85%) as a white solid. MS calcd. for C18H20N4O2 324, obsd. (ESI+) [(M+H)+] 325.

1. temperatureAfter cooling, to the mixture
2. extractionthe aqueous layer was extracted with ethyl acetate (20 mL×4)
3. dry with materialThe combined organic layers were dried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe residue was purified by flash column chromatography (10% methanol in dichloromethane)