反应详情

tert-Butyl (2S,4R)-4-hydroxy-2-(hydroxymethyl)pyrrolidine-1-carboxylate (500 mg; 2.3 mmol) in pyridine (20 mL) was cooled to 0° C. To this cooled solution was added a solution of p-toluenesulfonyl chloride (483 mg, 2.53 mmol) in pyridine (5 mL) over a period of 1 hour. The reaction mixture was allowed to slowly warm to ambient temperature and stirring was continued at ambient for 48 hours. The volatiles were removed in vacuo, and the residue was redissolved in toluene and concentrated again in vacuo. The crude material was triturated with ethyl acetate. This was further purified by chromatography on a 12 g silica gel column eluted with 5% ethyl acetate/hexanes for 3 minutes and then eluted with a gradient to 100% ethyl acetate over 20 minutes. The title compound was isolated as an oil (397 mg; 64% yield). 1H NMR (300 MHz, DMSO-d6) δ ppm 7.82-7.69 (m, 2H), 7.48 (d, J=7.9 Hz, 2H), 4.92 (d, J=2.8 Hz, 1H), 4.23-3.82 (m, 4H), 3.12 (dd, J=25.5, 13.9 Hz, 2H), 2.42 (d, J=3.6 Hz, 3H), 1.87 (d, J=20.3 Hz, 2H), 1.35 (dd, J=23.0, 13.0 Hz, 9H).

1. customThe volatiles were removed in vacuo
2. dissolutionthe residue was redissolved in toluene
3. concentrationconcentrated again in vacuo
4. customThe crude material was triturated with ethyl acetate
5. customThis was further purified by chromatography on a 12 g silica gel column
6. washeluted with 5% ethyl acetate/hexanes for 3 minutes
7. washeluted with a gradient to 100% ethyl acetate over 20 minutes