Reactions of 4-dialkylamino-5-methoxy-1,2-benzoquinones in acidic media: Selective C-alkylation or N-dealkylation

Article abstract of DOI:10.1016/0040-4020(96)00430-9

4-(N-methyl-alkylamino)-5-methoxy-1,2-benzoquinones 3, for which N-alkyl group R¹ can give rise to a stabilized carbonium ion, undergo selective acid-catalyzed rearrangements to 3-alkylated-1,2-benzoquinones 4. Aziridino- quinone 10c gives rise to the heterobicyclic 1,2-benzoquinone 11. When R¹ does not contain groups capable of stabilizing a positive charge, efficient and selective N-dealkylations occur. The mechanisms of these reactions are discussed.