The first catalytic enantioselectiveFriedel–Craftsalkylation of indoles with α,β-unsaturated trifluoromethyl ketones has been accomplished. The reaction was achieved in the presence of the Dy(OTf)3/Pybox complex, producing the desired products in high yields (up to 99%) with good enantioselectivities (up to 86% ee). The absolute stereochemistry of the resulting adducts was determined by X-ray analysis
the addition to various unsaturated carbonyl compounds, while calcium triflimide [Ca(NTf2)2] efficiently catalyzed the addition to nitroolefins. Friedel–Crafts alkylation of indole and its derivatives with a variety of electron-deficient alkenes catalyzed by Mg and Ca salts has been studied. The dependence of the results on the nature of the starting olefins, substituents on indole, and Michael acceptors