of β,γ-unsaturated α-keto esters in iPrOH alone was achieved by using asymmetric binary-acid catalysts. The presence of 0.2 mol% of a chiral phosphoric acid and 0.5 mol% Sc(OTf)3 is sufficient to obtain synthetically relevant β,γ-unsaturated α-hydroxyesters in excellent yields (up to 98%) and enantioselectivities (up to 99% ee). By DFT studies on the transferhydrogenation of 2-oxo-3-enoates, we have