反应详情

To a mixture of tert-butyl 1-oxa-6-azaspiro[2.5]octane-6-carboxylate (35.3 g, 16.55 mmol) and triphenylsilanethiol (48.4 g, 16.55 mmol) in anhydrous methanol (1.0 L) was added triethylamine (23.1 ml, 16.55 mmol) drop-wise over the course of 30 minutes. The reaction was stirred for 1 hour at room temperature and the methanol was evaporated under reduced pressure. The crude product was purified by flash column chromatography (SiO2, 5% EtOAc in hexanes to 40% EtOAc in hexanes) to afford 81% (33.1 g) pure final product. M.p.=54-55° C.; 400 MHz 1H NMR (CDCl3) δ: 3.97-3.78 (m, 2H), 3.19-3.08 (m, 2H), 2.61 (d, J=4.4 Hz, 2H), 1.70-1.55 (m, 2H), 1.50-1.38 (m, 11H); LCMS: 248 [M+H].

1. customthe methanol was evaporated under reduced pressure
2. customThe crude product was purified by flash column chromatography (SiO2, 5% EtOAc in hexanes to 40% EtOAc in hexanes)