1,2-Boron Shifts of β-Boryl Radicals Generated from Bis-boronic Esters Using Photoredox Catalysis
Daniel Kaiser, Adam Noble, Valerio Fasano and Varinder K. Aggarwal*
*School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.,
Email: v.aggarwal
bristol.ac.uk
D. Kaiser, A. Noble, V. Fasano, V. K. Aggarwal, J. Am. Chem. Soc., 2019, 141, 14104-14109.
DOI: 10.1021/jacs.9b07564
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Abstract
1,2-Bis-boronic esters are versatile intermediates that enable the rapid elaboration of simple alkene precursors. A photoredox-catalyzed mono-deboronation generates primary β-boryl radicals that undergo rapid 1,2-boron shift to form thermodynamically favored secondary radicals, allowing for selective transformation of the more hindered boronic ester.
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proposed mechanism
Key Words
1,4-addition, alkylboronates, photochemistry
ID: J48-Y2019
