2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → Ethyl 3,4-Diaminobenzoate

Participants

Reaction Steps

Step a A mixture of methyl 3-amino-4-hydroxybenzoate (2.5 g, 15 mmol) and methyl 4-formylbenzoate (2.46 g, 15 mmol) in methanol (75 mL) was stirred at rt overnight. The solvent was evaporated under reduced pressure and the remaining residue was dissolved in dichloromethane (150 mL). DDQ (3.5 g, 15.4 mmol) was added and the reaction mixture was stirred at rt for 1 h. Saturated NaHCO3 (200 mL) was added. The suspension was filtered off, the resulting solid was washed with saturated NaHCO3 (50 mL), water (50 mL), and ethyl acetate (100 mL) and dried in vacuo to give compound 1 (4 g, 86% yield) as yellow solid.

Provenance & Evidence