Imidazole → (2S,4R)-1-tert-Butyl 2-methyl 4-((tert-butyldimethylsilyl)oxy)pyrrolidine-1,2-dicarboxylate

Participants

Reaction Steps

To a solution of (2S,4R)-1-(tert-butoxycarbonyl)-4-hydroxy-2-methoxycarbonylpyrrolidine (21.46 g) and imidazole (7.74 g) in dichloromethane (150 ml) was added dropwise a solution of tert-butyldimethylsilyl chloride (14.67 g) in dichloromethane (30 ml) at room temperature. After two hours, resultant precipitate was filtered off, and the filtrate was washed in turn with water and brine. Evaporation of the solvent gave an oil, which was chromatographed on silica gel (500 ml) eluting with a mixture of hexane and ethyl acetate (2:1, V/V) to give (2S,4R)-4-(tert-butyldimethylsilyloxy)-1-(tert-butoxycarbonyl)-2-methoxycarbonylpyrrolidine (32.3 g).

Provenance & Evidence