Oxalyl chloride → methyl 2-(5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-2-oxoacetate

Participants

Reaction Conditions

Reaction Steps

Add oxalyl chloride (1.05 mL, 12.08 mmol) dropwise to a solution of 5,6dihydro-4H-pyrolo[3,2,1-ij]quinoline (1.67 g, 10.6 mmol) in 150 mL of anhydrous diethyl ether at 0° C. and stir the resulting solution at 0° C. for 40 minutes. Cool the mixture to −78° C. and slowly add sodium methoxide (42 mL, 21 mmol, 0.5 M in methanol). Upon completion of the addition, remove the dry ice bath and allow the reaction to warm to 20-24° C. over 2 hours. Dilute the mixture with ethyl acetate (200 mL), wash with water (100 mL) and separate the layers. Wash the organic layer with saturated aqueous sodium chloride (50 mL), dry over sodium sulfate, filter, and concentrate under reduced pressure. Dissolve the residue in ethyl acetate (100 mL), filter through a 2 inch plug of coarse silica gel, and concentrate under reduced pressure to give the title compound as a yellow solid (2.16 g, 84%).

Provenance & Evidence