Pi-Allyl Donicity Switch In Catalytic Asymmetric Allylation: Usability Of A Robust And Feasible Allyl Methyl Ether

A chiral CpRu(II)/p-TsOH combined catalyst is described for asymmetric allylation that reverses the pi-allyl donicity of AllX (All: allyl, X: leaving group) from "AllOAc > AllOPh > AllOH > AllOMe" to "AllOH > AllOMe > AllOPh > AllOAc". This represents a novel deviation from conventional Tsuji-Trost-Pd-based methods that operate under basic conditions. This is the first successful demonstration of endowing reactivity in chemically stable AllOMe, which should significantly expand the scope of synthetic possibilities.