Synthesis of 5-alkoxy-4-alkylamino-1,2-benzoquinones

Article abstract of DOI:10.1055/s-1995-4131

A simple and efficient method is described for a general synthesis of 4-dialkylamino-5-methoxy-1,2-benzoquinones 3 which involves, in polar solvents, a regioselective (>95%) nucleophilic monosubstitution by a wide range of secondary aliphatic amines on an easily prepared 1,2-quinone 1. Regioselectivity is not observed in the reaction of primary amines with 1, but a further reaction with an alcohol in basic medium allows valorization of the undesirable product.