Copper-catalyzed asymmetric dearomatizing amination of 2-naphthols: Csp2–N coupling via 1,3-reductive elimination

Abstract

An efficient catalytic asymmetric dearomatizing amination of 2-naphthols and phenols catalyzed by N,N′-dioxide-copper(I) complex as a chiral catalyst was presented. A variety of optically active β-naphthalenone compounds with a nitrogen-containing quaternary carbon stereocenter were obtained with high yield and enantioselectivity under mild reaction conditions. Mechanistic studies indicated that this Csp²–N dearomatizing coupling proceeds via 1,3-reductive elimination of phenolate-Cu^III-amino intermediate in five-membered ring transition states. The origin of enantioselectivity has also been elucidated based on density functional theory calculations.