Unexpected synthesis of trans-2,3-dimethoxy-3-(p-formylphenylamino)-4′-nitroflavanones
Abstract
The reaction of o-hydroxyacetophenones 1a-c with p-nitrobenzaldehyde in aqueous methanolic KOH leads to the formation of trans-2,3-dimethoxy-3-(p-formylphenylamino)-4′-nitroflavanones 2a–c, two of which have been structurally characterized by X-ray crystallography.