New insight into the mechanism of the reaction between α,β-unsaturated carbonyl compounds and triethylborane (Brown’s reaction)

A study of the reaction of α,β-unsaturated carbonyl compounds with triethylborane under free radical conditions (Brown’s reaction) including spectroscopic analyses (11B NMR, IR, EPR) of products and intermediates indicated that these reactions involve the prior formation of an ‘α,β-unsaturated carbonyl compound–organoborane’ complex.