反应详情

Carbon tetrabromide (9.0 g, 27 mmol) and triphenyl phosphine (1.2 g, 4.5 mmol) were added to a solution of compound 2 (1.8 g, 4.5 mmol) in dry CH2Cl2 (100 mL). After stirring the reaction mixture for 5 h, the solvent was concentrated in vacuo and the residue was loaded onto a silica gel gravity column (200 g) and eluted with CH2Cl2:MeOH 100:0 to 20:1 (v/v) to afford compound 3 as a colorless oil (1.9 g, 91%).

1. concentrationthe solvent was concentrated in vacuo
2. washeluted with CH2Cl2:MeOH 100:0 to 20:1 (v/v)