Synthesis of 5-substituted 4,4-disubstituted 2-cyclohexen-1-ones by electro-generated base promoted Michael addition of 4,4-disubstituted 2,5-cyclohexadien-1-ones

5-Substituted 4,4-dialkoxy-2-cyclohexen-1-ones were electro-synthesized from 4,4-disubstituted 2,5-cyclohexadien-1-ones, which were obtained from 1,4-dialkoxybenzene derivatives by electrolysis, by electro-generated base (EG-base)-promoted Michael addition with CH₂E₂ (E = CO₂R, COMe) in moderate to almost quantitative yield. The cyclohexenone derivatives were found to be a good precursor of benzofuranone derivatives through acid-promoted intramolecular lactonization.