Trifluoroacetic acid → HCID 67884061, compound

Participants

Reaction Steps

4.05 g (20 mmol) of m-chloroperbenzoic acid are added in portions at room temperature, with stirring, to a solution of 2.3 g (10 mmol) of (9bR*,13aR*)-2-oxo-1,4,5,10,11,12,13,13a-octahydro-2H-pyrrolo[2',1':3,4]pyrazino[2,1-i]indole in 50 ml of dichloromethane (the exothermic reaction is maintained at room temperature using an ice-bath). 2.28 g (20 mmol) of trifluoroacetic acid are then added dropwise to the reaction mixture which is then stirred for 16 hours at room temperature. The reaction mixture is diluted with 100 ml of dichloromethane and then washed in succession with sodium hydrogen sulfite solution (5%) and sodium hydrogen carbonate solution (5%). The organic phase is separated off, dried over sodium sulfate and concentrated by evaporation in vacuo. The crude product obtainable in that manner is chromatographed on 210 g of silica gel (0.040-0.063 mm) using trichloromethane as eluant. In this manner (9aR*,9bR*,13aR*)-2,7-dioxo-1,4,5,7,9a,10,11,12,13,13a-decahydro-2H-pyrrolo[2',1' :3,4]pyrazino[2,1-i]indole is obtained in the form of an oil, which is crystallised from dichloromethane/diethyl ether and melts at 159°-162°.

Provenance & Evidence