Pd-Catalyzed Dearomatization of Anthranils with Vinylcyclopropanes by [4+3] Cyclization Reaction.
Qiang ChengJia-Hao XieYue-Cheng WengShu-Li YouPublished in: Angewandte Chemie (International ed. in English) (2019)
Dearomatization of anthranils with vinylcyclopropanes (VCPs) by Pd-catalyzed [4+3] cyclization reaction has been realized. In the presence of a catalytic amount of borane as an activator, bridged cyclic products were obtained in good to excellent yields with excellent stereoselectivities. By introducing a chiral PHOX ligand (L5), asymmetric dearomatization reactions of anthranils with vinylcyclopropanes proceeded with excellent enantioselectivity. Borane plays a key role for the reactivity, likely owing to the formation of a borane-anthranil complex which has been confirmed by NMR experiments.