反应详情

To a suspension of 5-bromo-3-hydroxy-3-(7-hydroxy-2,3-dihydro-1,4-benzodioxin-6-yl)-1-(pyridin-2-ylmethyl)-1,3-dihydro-2H-indol-2-one (3.60 g, 8.10 mmol) in triethylsilane (10 mL) at 0° C. was added trifluoroacetic acid (40 mL). The solution was allowed to warm to ambient temperature over 2 h and was stirred for a further 4 h. The reaction mixture was concentrated in vacuo and saturated aqueous sodium bicarbonate and ethyl acetate were added to the residue, causing a precipitate to be deposited. The solid was collected by filtration and washed sequentially with diethyl ether and hexanes to afford 5-bromo-3-(7-hydroxy-2,3-dihydro-1,4-benzodioxin-6-yl)-1-(pyridin-2-ylmethyl)-1,3-dihydro-2H-indol-2-one (4.03 g, 100%) as a pale yellow solid: 1H NMR (300 MHz, DMSO-d6) δ 8.59-8.55 (m, 1H), 7.90-7.80 (m, 1H), 7.44-7.37 (m, 1H), 7.34-7.27 (m, 1H), 7.07 (s, 1H), 6.82-6.68 (m, 2H), 6.27 (s, 1H), 5.17-4.93 (m, 2H), 4.84 (s, 1H), 4.23-4.06 (m, 4H). MS (ES+) m/z 452.9 (M+1), 454.9 (M+1).

1. concentrationThe reaction mixture was concentrated in vacuo and saturated aqueous sodium bicarbonate and ethyl acetate
2. additionwere added to the residue
3. filtrationThe solid was collected by filtration
4. washwashed sequentially with diethyl ether and hexanes