Synthesis of the aphin-related (±)-7,9-dideoxyquinone A and (±)-7,9-dideoxyquinone A′

Abstract

The oxidative cyclisation of 3-(1-hydroxyethyl)-,1,4-dimethoxy-2-prop-1-enylnaphthalene with four equivalents of ceric ammonium nitrate to afford two 4-hydroxy-1,3-dimethylnaphtho[2,3-c]pyran-5,10-quinones with the same stereochemistry as quinones A and A′, derivatives of the aphid pigments protoaphin-fb and protoaphin-sl, is described. Certain aspects of the mechanism have been established.