Catalytic Enantioselective ?-selective Addition Of 2-allylazaarenes To Activated Ketones

Azaarenes containing an embedded imine(C=N)exhibit electron-withdrawing properties,which have allowed 2-alkylazaarenes as nucleophiles and 2-alkenylazaarenes as electrophiles in catalytic enantioselective reactions to access valuable ?-and/or ?-functionalized chiral azaarenes.Herein,we report the first example of 2-allylazaarenes in asymmetric catalysis.Highly ?-selective allylation was demonstrated for activated ketones,including isatins and trifluoromethyl ketones.In the presence of amino acid-based tertiary amine or quaternary ammonium salt catalyst,two series of tertiary hydroxyl-containing biologically potential scaffolds were installed at the remote ?-position of azaarenes in good chemical yields,excellent enantioselectivities and E/Z ratios.The success of current ?-selective reactions should provide inspiration for expansion to other allylazaarene derivatives and would open up new paradigms for the synthesis of chiral ?-and/or ?-functionalized azaarenes.