Oxalic acid dihydrate → 6,7-Dibromo-1,4-dihydroquinoxaline-2,3-dione

Participants

Reaction Conditions

Reaction Steps

A mixture of 4,5-dibromo-1,2-phenylenediamine (1.862 g, 7.0 mmol) and oxalic acid dihydrate (1.06 g, 8.4 mmol) in 2N HCl (100 mL) was heated at 125° C. for 2 h then allowed to cool to 25° C. The solid was collected by vacuum filtration, washed with water and dried at 40° C. under 1 mmHg for 10 h affording 2.053 g (92%) of the title compound as a light brown powder. 1H NMR (DMSO-d6) 11.995 (s, 2H), 7.361 (s, 2H).

Provenance & Evidence