反应详情

To a mixture of (S)-methyl 3-amino-2-(tert-butoxycarbonyl)propanoate ii (1.6 g, 7.3 mmoL) in DCM (50 mL) was added DIPEA (1.64 mL, 9.4 mmoL) and 2-nitrobenzene sulfonyl chloride (1.62 g, 7.3 mmoL). The mixture was stirred at rt for 2 h. It was then concentrated, dissolved in ethyl acetate, which was then washed with sat. sodium bicarbonate, brine and dried over magnesium sulfate. It was then filtered, concentrated to yield 2.9 g (98%) of (S)-methyl 2-(tert-butoxycarbonyl)-3-(2-nitrophenylsulfonamido)propanoate iii as a yellow foam. 1H NMR (CD3OD, 300 MHz) δ 1.41 (s, 9H), 3.36–3.51 (m, 2H), 3.71 (s, 3H), 4.22 (m, 1H), 7.80–7.90 (m, 3H), 8.07–8.10 (m, 1H).

1. concentrationIt was then concentrated
2. dissolutiondissolved in ethyl acetate
3. washwhich was then washed with sat. sodium bicarbonate, brine
4. dry with materialdried over magnesium sulfate
5. filtrationIt was then filtered
6. concentrationconcentrated