Water → HCID 54214671, compound

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 2-(3,4-dichlorobenzyl)-1,3-dioxo-1,2,3,4-tetrahydropyrrolo[1,2-a]pyrazine-4-carboxylic acid benzyl ester (9.4 g) in anhydrous dimethylformamide (40 ml) was added portionwise sodium hydride (63% dispersion in mineral oil, 0.7 g) under ice cooling, while a stream of nitrogen was passed over the mixture. The resulting mixture was stirred at 25° C. for 1 hour and thereto was added tert-butyl bromoacetate (4.3 g). The mixture was stirred at 25° C. for 15 hours, poured into water, and extracted with ethyl acetate. The extracts were dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was chromatographed on silica gel using n-hexane/ethyl acetate (20:1) as the eluent. Fractions containing the title compound were pooled and evaporated under reduced pressure. The residue was recrystallized from ethyl acetate/n-hexane to give the title compound (9.2 g, 78.0%) as colorless crystals, mp 86°-88° C.

Provenance & Evidence