Synthesis of 3-substituted 2-aminonaphtho[2,3-b]furan-4,9-diones from 2-hydroxy-1,4-naphthoquinone and nitroalkenes

The efficient base-catalyzed synthesis of 3-substituted 2-aminonaphtho[2,3-b]furan-4,9-dione derivatives from readily available precursors such as 2-hydroxy-1,4-naphthoquinone and nitroalkenes under aqueous conditions is described. Interesting features of this methodology are the conversion of a nitro functionality into an amino functionality in the absence of a reducing agent and the development of a three component reaction for accessing the same product from an aldehyde, 2-hydroxy-1,4-naphthoquinone and nitromethane. 3-Substituted 2-aminonaphtho[2,3-b]furan-4,9-diones have been synthesized from 2-hydroxy-1,4-naphthoquinone and nitro alkenes under aqueous conditions. In this methodology, a nitro moiety is converted into an amino functionality in the absence of a reducing agent. The same products were obtained from a three-component reaction involving aldehydes, 2-hydroxy-1,4-naphthoquinone, and nitromethane.