Sodium Bicarbonate → HCID 53808462, compound

Participants

Reaction Steps

A mixture of 2,3-dichloro-6,7-dimethyl-5-nitroquinoxaline (from step (b), 8.33 g, 30.6 mmol) and stannous chloride dihydrate (34.54 g, 153 mmol) in ethyl acetate (300 ml) was heated at reflux for 11 hours. A further portion of stannous chloride dihydrate (13.82 g, 61.2 mmol) was added and the mixture was heated for 2 hours, cooled and diluted with ethyl acetate (500 ml). The mixture was added to saturated aqueous sodium bicarbonate (200 ml) and filtered, washing the filter cake well with ethyl acetate. The organic layer was separated, washed with saturated aqueous sodium bicarbonate (3×100 ml), dried (MgSO4) and concentrated under reduced pressure. The residue was purified by flash chromatography (gradient elution with methanol/dichloromethane) to afford 5-amino-2,3-dichloro-6,7-dimethylquinoxaline (6.15 g, 83%), as an orange solid, m.p. 178-180° C.

Provenance & Evidence