Ethyl diazoacetate → Ethyl 5-benzyl-4,6-dioxo-1,3a,4,5,6,6a-hexahydropyrrolo[3,4-c]pyrazole-3-carboxylate

Participants

Reaction Steps

Ethyl diazoacetate (30.3 mL, 288.5 mmol) was added dropwise over a period of 30 min to a solution of N-benzylmaleimide (49.5 g, 264.7 mmol) in diethyl ether (300 mL) and the mixture was stirred for 4 days at room temperature. The resulting precipitate was filtered off, washed with diethyl ether (100 mL) and dried under vacuum to provide title compound as a white solid (72 g, 90%). Method B HPLC-MS: MH+ requires m/z=302. Found: m/z=302, Rt=1.74 min (83%).

Provenance & Evidence