反应详情

A solution of tert-butyl 4-[(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-ylidene)(hydroxy)methyl]piperidine-1-carboxylate (8.99 g, 25.3 mmol) and t-butyl N-(t-butoxycarbonyloxy)carbamate (5.90 g, 25.3 mmol) in toluene (200 mL) was stirred at 65° C. for 14 h, then at rt for 36 h. The reaction mixture was concentrated and the residue was purified by flash chromatography (silica, 25% ethyl acetate/hexanes) to afford tert-butyl 4-(3-{(tert-butoxycarbonyl)[(tert-butoxycarbonyl)oxy]amino}-3-oxopropanoyl)piperidine-1-carboxylate. H NMR analysis was consistent with product but complex due to carbamate rotamers.

1. concentrationThe reaction mixture was concentrated
2. customthe residue was purified by flash chromatography (silica, 25% ethyl acetate/hexanes)