Oxygenophilic organoaluminum-mediated conjugate addition of alkyllithium and Grignard reagents to quinone monoketals and quinol ethers. The directing effect of a methoxy group on the 1,4-addition process

Complexation of quinone monoketals and quinol ethers with methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide), the MAD reagent, followed by addition of organolithium or Grignard reagents gives products from 1,4-addition of the organometallic reagent to the α,β-unsaturated ketone moiety. The success of these 1,4-additions stands in marked contrast to reported MAD-mediated additions of alkyllithium reagents to cyclohexenone, which afford 1,2-addition products.