Synergistic interplay between ligand- and metal-centered chirality in iridium-catalyzed enantioselective C(sp3)–H borylation of cyclopropanols

Abstract

Density functional theory calculations were performed to investigate the Ir/CBL-catalyzed C(sp³)–H borylation of cyclopropanols. The computations indicate that the reaction follows an Ir(III)/Ir(V) catalytic cycle with six- and seven-coordinate intermediates, involving both Λ- and Δ-configured iridium species. The metal-centered chirality plays a key role in determining the enantioselectivity. The ortho-substituent on the N-aryl group of the ligand has a significant impact on the Δ-configured C(sp³)–B reductive elimination, which can modulate the relative reactivity of the Λ- and Δ-configured intermediates, accounting for the experimentally observed enantioselectivities. The results reveal a synergistic interplay between ligand- and metal-centered chirality, which together dictate the observed enantioselectivity.