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  • An I2-catalyzed, Visible-Light Photoredox-Mediated Radical Conversion of a-Nitrocarbonyls to Nitrile Oxides. Catalytic Access to Isoxazolines and Isooxazoles from Alkenes and Alkynes
Title: An I2-catalyzed, Visible-Light Photoredox-Mediated Radical Conversion of a-Nitrocarbonyls to Nitrile Oxides. Catalytic Access to Isoxazolines and Isooxazoles from Alkenes and Alkynes
A visible light-mediated, I2-catalyzed intermolecular transformation of alkenes, conjugated dienes, styrenes and alkynes to isooxazoline and isoxazole motifs with a-nitrocarbonyls and analogs is reported. The reaction is also applicable to 1,1-disubstituted terminal, 1,2-disubstituted internal and trisubstituted alkenes, and tolerates a range of functional groups including epoxides, heterocycles, phosphates, free alcohols and thiocyanates. Mechanistic studies reveal that a-nitrocarbonyls are first converted to -carbonyl radicals followed by their conversion to acyl nitrile oxides, which subsequently undergo [3 + 2] dipolar cycloaddition reactions with the unsaturated molecules.  more » « less
Award ID(s):
2102394
PAR ID:
10616753
Author(s) / Creator(s):
;
Publisher / Repository:
ChemRxiv
Date Published:
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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