Ni-Catalyzed Intermolecular Allylic Dearomatization Reaction of Tryptophols and Tryptamines.

An efficient synthesis of pyrrolidinoindolines and tetrahydrofuranoindolines was achieved via Ni-catalyzed allylic dearomatization reactions of tryptophols and tryptamines. In the presence of 13 mol % of Ni(cod)2 and 10 mol % DPEphos, both tryptophols and tryptamines could react with aryl vinyl carbinols smoothly under mild conditions, affording 3-cinnamyl indolines in moderate to good yields with high chemo- and regioselectivity. This method features a broad substrate scope, a commercially available and inexpensive catalytic system, and readily available substrates.