Remote Asymmetric ε-or η-Position Substitution Reactions of Naphthalene-Blocked Alkynes

Achieving asymmetric remote ε/η-position substitution of alkynes at sites far from the catalytic center poses considerable challenges, due to the requirements for high complexity, diverse structures and precise stereocontrol. To tackle this challenge, novel yne-naphthalene esters were developed using a naphthalene ring spacer and alkynyl coppermediated electron transfer, remote leaving group cleavage enabled asymmetric remote ε/η-arylation with 5-aminopyrazoles, affording diarylmethyl/triarylmethyl products in high yields with good to excellent enantioselectivities for the first time. Additionally, a gram-scale experiment and further derivatizations of chiral remote ε/η-arylation of yne-naphthalene esters were performed to validate the practicability of the methodology and the potential transformations of the products. Finally, control experiments, nonlinear effects, UV absorption spectra, and Job's plot further validated the scientific rationality of our proposed mechanism. Meanwhile, DFT calculations suggest that N-H ... π interactions were found to play a key role in the stereoselective control.