反应详情

N-Bromosuccinimide (NBS) (0.507 g, 2.85 mmol) was added to a solution of 3-t-butyldimethylsiloxy-4-methyl benzamide (Compound 7.1) in 30 mL CCl4. The mixture was irradiated with a 275 W sunlamp (Sears, #34-7105) at 60° C. Each irradiation took 10 minutes followed by 10 minutes to let the lamp cool down. It took 2 hours of irradiation over a period of 4 hours to complete the reaction. After the solvent was removed at reduced pressure, the residue was subjected to flash silica gel chromatography to yield the product as a white solid (0146 g, y=81.7%). 1H NMR (CDCl3) δ 0.318 (s,6H), 1.05 (s,9H), 4.51 (s,2H), 6.10 (b, 2H), 7.25 (d,J=7.8 Hz, 1H), 7.32 (s,1H), 7.39 (d,J=7.9 Hz, 1H); --C NMR (CDCl3 ) δ 4.08, 18.28, 25.76, 27.87, 117.99, 118.07, 119.49, 131.23, 132.54, 134.97, 168.46.

1. customThe mixture was irradiated with a 275 W sunlamp (Sears, #34-7105) at 60° C
2. customEach irradiation
3. waitfollowed by 10 minutes
4. temperaturecool down
5. customIt took 2 hours of irradiation over a period of 4 hours
6. customthe reaction
7. customAfter the solvent was removed at reduced pressure