反应详情

A suspension of 4,4-dimethyl-5α-chola-8,14-dien-3β,24-diol (500 mg, 1.29 mmol), N-methylmorpholine-N-oxide (600 mg, 5.2 mmol), TPAP (45 mg, 0.13 mmol) and crushed molecular sieves (2 g) in dichloromethane (5 mL) was stirred for 30 minutes at room temperature. Addition of ether (15 mL) and filtration through kieselguhr gave a dark brown solution which was concentrated under reduced pressure and purified by chromatography (Eluant: 3 hexane: 1 ethyl acetate) to give the 3-oxo-4,4-dimethyl-5α-chola-8,14-dien-24-aldehyde (345 mg, 70%) as a white solid with melting point 96.5-97° C.

1. customgave a dark brown solution which
2. concentrationwas concentrated under reduced pressure
3. custompurified by chromatography (Eluant: 3 hexane: 1 ethyl acetate)