2(1H)-Quinoxalinone, 3,4-dihydro- → tert-butyl N-(3-(1,2,3,4-tetrahydroquinoxalin-3-on-1-carbonyl)benzyl)-N-methylcarbamate

Participants

Reaction Steps

WSC.HCl (640 mg, 3.4 mmol) and 4-(dimethylamino)pyridine (330 mg, 2.7 mmol) were added to a solution of tert-butyl N-(3-carboxybenzyl)-N-methylcarbamate (700 mg, 2.6 mmol) and 1,2,3,4-tetrahydroquinoxalin-2-one (440 mg, 2.9 mmol) in dichloromethane (20 ml). The mixture was stirred for 18 h, reduced in vacuo and taken up in ethyl acetate. This solution was washed with 0.3N potassium hydrogen sulphate and saturated sodium hydrogen carbonate solutions, dried and reduced. Chromatography (50% EtOAc/50% 60-80 pet.ether) afforded tert-butyl N-(3-(1,2,3,4-tetrahydroquinoxalin-3-on-1-carbonyl) benzyl)-N-methylcarbamate (280 mg, 27%) as an orange oil.

Provenance & Evidence