反应详情

A stirred solution of tert-butyl-N-[3-(hydroxymethyl)benzyl]-N-methylcarbamate (4.2 g, 16.7 mmol) in CH2Cl2 (150 ml) at 0° C., was treated with carbon tetrabromide (8.0 g, 24.1 mmol) and triphenyl phosphine (6.35 g, 24.21 mmol). The resultant solution was warmed to room temperature and stirred for 4 days. The resultant mixture was evaporated to dryness and the residue purified by chromatography (SiO2, gradient elution with 100% hexane; 99:1 hexane:ethyl acetate; 95:5 hexane: ethyl acetate) to give the desired product (3.32 g, 60%). 1H NMR (CDCl3) δ 1.50 (s, 9H), 2.80 (s, br, 3H), 4.20 (s, 2H), 4.30 (s, 2H), 7.15 (m, 1H), 7.25 (m, 1H), 7.30 (m, 2H). LRMS m/z=333.2 (M+18)+.

1. customThe resultant mixture was evaporated to dryness
2. customthe residue purified by chromatography (SiO2, gradient elution with 100% hexane; 99:1 hexane:ethyl acetate; 95:5 hexane: ethyl acetate)