An efficient N,N’-dioxide-scandium(III) complex catalytic system has been developed for the asymmetric dearomatization of β-naphthols through conjugateaddition to alkynones. A variety of Z-predominated β-naphthalenone compounds were obtained in moderate to high yields with excellent enantioselectivities (up to 98% ee). Moreover, a possible transition state was proposed to explain the origin of the
Highly selective: The title reaction is achieved with high enantiomeric and geometric control and thermodynamically unstable (Z)‐enone derivatives are obtained as the major products (see scheme). The procedure tolerates a wide range of substrates to generate optically active pyrazolones with vinyl‐substituted quaternary stereocenters.
An N,N′‐dioxide/zinc bis(trifluoromethylsulfonyl)imide complex has been developed as an efficient catalyst for the highly enantioselective Diels–Alderreaction of cyclopentadiene with alkynones. Various 2‐acyl substituted norbornadiene derivatives were obtained in moderate to high yields (up to 99 %) with good enantiomeric excesses (up to 95 %).