Copper Bromide–Catalyzed C-Alkylation of 2-Amino-1,4-Naphthoquinone: New Synthesis of 1-Azaanthraquinones

Abstract

Copper(I) bromide catalyzes the regioselective Michael addition reaction of 2-amino-1,4-naphthoquinone (5) with methyl vinyl ketone and 2-propenal to provide easy access to C-alkylated quinone derivatives, useful precursors of 1-azaanthraquinones.

Keywords:

• 2-Amino-1,4-naphthoquinone
• 1-azaantraquinones
• catalysts
• CuBr
• Michael addition

ACKNOWLEDGMENTS

We are grateful to Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT, Research Grant 1060592) and Comisión Nacional de Investigación Científica y Tecnológica (CONICYT, fellowship to L. C. and Research Grant AT24080019).