1,1'-Carbonyldiimidazole → Tert-butyl 3-[methoxy(methyl)carbamoyl]pyrrolidine-1-carboxylate

Participants

Reaction Steps

Add portionwise 1,1′-carbonyldiimidazole (4.14 g, 25.6 mmol) to a solution of pyrrolidine-1,3-dicarboxylic acid 1-tert-butyl ester (5.0 g, 23.2 mmol) in dichloromethane (77 mL) at RT. Allow the mixture to stir for 15 min. Add slowly N,O-dimethylhydroxylamine hydrochloride (2.7 g, 27.9 mmol). Stir the reaction mixture at RT overnight. Dilute the mixture with dichloromethane (200 mL), wash with water (2×300 mL), brine (200 mL), dry over Na2SO4, filter, and concentrate. Purify the crude material by flash chromatograph, eluting with 50-100% ethylacetate/hexane to give 5.36 g (89%) of the title compound. LC-MS/ES m/z 203.0 [M−tertBu+H]+.

Provenance & Evidence