Rapid Injection NMR Reveals η³ ‘π-Allyl’ Cu^III Intermediates in Addition Reactions of Organocuprate Reagents

By using rapid injection NMR, it has now been possible to prepare and characterize the η³ ‘π-allyl’ copper­(III) intermediate that has been proposed for addition reactions of organocopper­(I) reagents and α,β-unsaturated carbonyl compounds