Copper‐catalyzedconjugateaddition: A highlyenantioselectiveconjugateaddition of cyclicdiketones to β,γ‐unsaturated α‐ketoesters was achieved by using a two‐carbon‐linked N,N′‐dioxide‐Cu(OTf)2complex. Excellent yields (up to 99 %) and enantioselectivities (up to 99 % ee) were obtained with 2 mol % catalyst loading (see scheme). By using this method, adducts could be easily transformed into hexahydroquinolines
The dinuclear zinc–ProPhenol complex is applied as efficient catalyst in the highly stereoselective tandem Michael addition/acetalization reactions of cyclic 1,3-diketones and β,γ-unsaturatedα-ketoesters. A variety of substrates are well-tolerated, and a broad range of synthetically and pharmaceutically useful chiral chromene derivatives are directly produced in good yields of up to 96% and good