N-cyclopropyl-N-(2-nitro-phenyl)-oxalamic acid methyl ester → 1-Cyclopropyl-4-hydroxy-1,4-dihydro-quinoxaline-2,3-dione

Participants

Reaction Steps

To a solution of N-cyclopropyl-N-(2-nitro-phenyl)-oxalamic acid methyl ester (45.0 g, 0.17 mol, 1.0 equiv) in methanol (400 mL) was added palladium on carbon (4.52 g, 0.0043 mol, 0.025 equiv; 10% Pd/C; [CAS RN 7440-05-3]) and the reaction mixture stirred under an atmosphere of hydrogen (1.2 bar) at rt for 2 h. The reaction mixture was diluted with ethyl acetate (400 mL), filtered over Celite® and the solvent mixture removed by evaporation under reduced pressure to give 31.2 g (84%) of the title compound as a light yellow solid. MS (ISN): 219.1 [M+H]+.

Provenance & Evidence