反应详情

N-Bromosuccinimide (0.90 g, 5.06 mmol) was added to a stirred solution of the compound from Step 2 (1.04 g, 4.60 mmol) in CCl4 (150 ml) followed by a catalytic amount of azobis (isobutyronitrile). After the mixture was refluxed for 3 h., the precipitated solid was removed by filtration and the solvent was evaporated in vacuo. The residue was stirred for 10 min. in 15 ml Et2O, filtered and dried to give 0.69 g of the title compound, m.p. 155°-156° C.

1. temperatureAfter the mixture was refluxed for 3 h.
2. customthe precipitated solid was removed by filtration
3. customthe solvent was evaporated in vacuo
4. filtrationfiltered
5. customdried