反应详情

To a stirred solution of the product of step 1 (12.3 g, 35.6 mmol) in methylene chloride (200 mL) was added 2-nitrobenzenesulfonyl chloride (9.00 g, 40.6 mmol) followed by triethylamine (6.4 mL, 46 mmol). After 30 minutes the reaction was concentrated and the residue partitioned between ethyl acetate and aqueous sodium bicarbonate solution. The organic layer was dried (sodium sulfate) and concentrated. The resulting amber foam was purified by flash chromatography over silica (hexane/ethyl acetate) to afford 14.0 g (74%) of product as a colorless foam: 1H NMR (CDCl3) δ 7.95-7.87 (m, 1H), 7.76-7.62 (m, 3H), 7.35-7.15 (m, 10H), 7.06-6.94 (m, 3H), 6.90-6.83 (m, 2H), 6.42 (t, J=5.6, 1H), 5.80 (d, J=5.8, 1H), 4.12 (t, J=8.1, 1H), 4.01-3.82 (m, 3H), 3.18-3.08 (m, 1H), 2.68-3.57 (m, 1H) ppm.

1. concentrationAfter 30 minutes the reaction was concentrated
2. customthe residue partitioned between ethyl acetate and aqueous sodium bicarbonate solution
3. dry with materialThe organic layer was dried (sodium sulfate)
4. concentrationconcentrated
5. customThe resulting amber foam was purified by flash chromatography over silica (hexane/ethyl acetate)