Visible Light-induced Halogen-atom Transfer by N-heterocyclic Carbene-ligated Boryl Radicals for Diastereoselective C(sp)-C(sp) Bond Formation

Overview

Journal Chem Sci

Publisher Royal Society of Chemistry

Specialty Chemistry

Date 2024 Aug 26

PMID 39184300

Authors

Luca Capaldo

Ting Wan

Robin Mulder

Jonas Djossou

Timothy Noel

Affiliations

Soon will be listed here.

Abstract

Photoinduced halogen-atom transfer (XAT) has rapidly emerged as a programmable approach to generate carbon-centered radical intermediates, mainly relying on silyl and α-aminoalkyl radicals as halogen abstractors. More recently, ligated boryl radicals have also been proposed as effective halogen abstractors under visible-light irradiation. In this study, we describe the use of this approach to enable C(sp)-C(sp) bond formation radical addition of carbon-centered radicals generated XAT onto chloroalkynes. Our mechanistic investigation reveals a complex interplay of highly reactive radical intermediates which, under optimized conditions, delivered the targeted vinyl chlorides in excellent yields and : ratios. Finally, we demonstrated the synthetic value of these products in transition metal-based cross-coupling reactions.

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