反应详情

A solution of n-BuLi (2.5 M, 3.80 mL) was added to a mixture of PPh3.MeI. (4.092 g, 10.13 mmol) in THF at −10. The mixture was stirred for 1 h at the same temperature, and then 6-bromo-2-phenylchroman-4-one (2 g, 6.62 mmol) was added. The mixture was allowed to warm to room temperature and stirred for 3 h. The resulting mixture was concentrated and purified by column chromatography to give 6-bromo-4-methylene-2-phenylchroman (400 mg, 20%). 1H-NMR (CDCl3): 2.76 (m, 2H), 4.90 (d, 1H), 5.01 (m, 1H), 5.48 (d, 1H), 6.76 (d, 1H), 7.31 (m, 6H), 7.62 (d, 1H).

1. stirringstirred for 3 h
2. concentrationThe resulting mixture was concentrated
3. custompurified by column chromatography