反应详情

To a magnetically stirred solution of 2-methyl-3-phenyloctan-4-one (Intermediate IIa-1) (4.31 gram, 0.02 mol) in CCl4 (40 ml) was added a catalytic amount of dibenzoyl peroxide and NBS (6.56 gram). The resulting mixture was heated for 6 hours at reflux temperature. The obtained mixture was allowed to attain room temperature. The formed precipitate was removed by filtration. The filtrate was concentrated to give crude 2-methyl-3-bromo-3-phenyloctan-4-one (intermediate IIb-1)—contaminated with some starting material—as a dark-colored oil (6.77 gram). 1H-NMR (400 MHz, CDCl3) Characteristic signals: δ 0.68 (d, J=6, 3H), 0.78 (t, J=7, 3H), 1.08 (d, J=6, 3H).

1. temperatureThe resulting mixture was heated for 6 hours
2. temperatureat reflux temperature
3. customto attain room temperature
4. customThe formed precipitate was removed by filtration
5. concentrationThe filtrate was concentrated