[CH3:1][C:2]1([CH3:13])[O:6][B:5]([OH:7])[C:4]2[CH:8]=[CH:9][C:10]([CH3:12])=[CH:11][C:3]1=2.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1.C1C(=O)N([Br:39])C(=O)C1.O>C(Cl)(Cl)(Cl)Cl>[Br:39][CH2:12][C:10]1[CH:9]=[CH:8][C:4]2[B:5]([OH:7])[O:6][C:2]([CH3:13])([CH3:1])[C:3]=2[CH:11]=1To a solution of 3,3,5-trimethylbenzo[c][1,2]oxaborol-1(3H)-ol (5.0 g, 28.4 mmol) in CCl4 (50 mL) at rt was added benzoyl peroxide (0.7 g, 2.8 mmol) following by NBS (5.0 g, 28.4 mmol). The reaction mixture was refluxed overnight, cooled to rt and treated with water. The aqueous layer was extracted with EA (20 mL×3). The organic layer was washed with brine, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by column chromatography to give the product (4.5 g, yield 62%) as yellow oil. MS: 255 & 257 [M+H]+.
Loading…
