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Updated: Dec 27, 2025

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
σ-Bond initiated generation of aryl radicals from aryl diazonium salts
Elene Tatunashvili1, Bun Chan2, Philippe E Nashar1
1School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia. christopher.mcerlean@sydney.edu.au.
Abstract:
σ-Bond nucleophiles and molecular oxygen transform aryl diazonium salts into aryl radicals. Experimental and computational studies show that Hantzsch esters transfer hydride to aryl diazonium species, and that oxygen initiates radical fragmentation of the diazene intermediate to produce aryl radicals. The operational simplicity of this addition-fragmentation process for the generation of aryl radicals, by a polar-radical crossover mechanism, has been illustrated in a variety of bond-forming reactions.
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