反应详情

A solution of methyl 4-(t-butyldimethylsilyloxy)-3-(2-propen-1-yl)benzoate (14.4 g) (obtained as described in International patent application, publication no. WO 91/11999) in methanol (280 ml) was catalytically hydrogenated over 10% palladium on carbon (2.9 g) at 3 atmospheres pressure for 2 hours. The catalyst was removed by filtration through diatomaceous earth and the filtrate was concentrated by evaporation. The residue was purified by flash chromatography, eluting with ethyl acetate/hexane (1:3 v/v), to give methyl 4-(t-butyldimethylsilyloxy)-3-propylbenzoate (B) (11.7 g) as an oil; NMR: 0.25(s, 6H), 0.95(t, 3H), 1.0(s, 9H), 1.5-1.7(m, 2H), 2.6(t, 2H), 3.9(s, 3H), 6.8(d, 1H), 7.8(dd, 1H), 7.8(s, 1H).

1. customThe catalyst was removed by filtration through diatomaceous earth
2. concentrationthe filtrate was concentrated by evaporation
3. customThe residue was purified by flash chromatography
4. washeluting with ethyl acetate/hexane (1:3 v/v)