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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| http://dx.doi.org/10.1039/d4sc02962c | DOI Listing |
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