New reactions of 2,3-diaminonaphthaline with carbonyl electrophiles

The reaction of 2,3-diaminonaphthalene with dimedone gave 3-[(3-amino-2-naphthyl)amino]-5,5-dimethylcyclohex-2-en-1-one that reacts with alloxan to afford a product of addition at the enamine moiety. The latter is converted to a spiro derivative on heating in CF₃COOH, or undergoes condensation with 2,6-di-tert-butyl-p-benzoquinone to give a benzophenazinone derivative with a sterically hindered phenol substituent.