An Enantioselective Alkene Aminoarylation to Form Chiral Indolines via Electrostatically-Directed Palladium Catalysis.

Abstract

Most design strategies in asymmetric transition metal catalysis invoke repulsive interactions between ligand and substrate. Yet those that incorporate attractive interactions can offer advantages, such as rate acceleration and greater generality, due to the fundamentally different mode of operation. Here we deploy electrostatically-directed Pd catalysis using the chiral sulfonated ligand sSPhos to realize an asymmetric aminoarylation of ortho-allyl anilines under mild conditions. A wide variety of substituted aryl bromides and anilines provide access to 2-benzylindolines with high enantioselectivity. Our study uncovers trends relating the electronics of both coupling partners to ee. These trends allowed tuning of the sulfonamide protecting group to enable good results across a broader range of substrates.