Straightforward α-allylation of carbonyl compounds with alkenes via α-carbonyl radical intermediates†
Abstract
We report that the direct oxidative cross-coupling of carbonyl compounds with simple alkenes is realized to synthesize α-allylated carbonyl compounds by identifying the bisphosphine ligand BINAP that enables the copper catalyst to integrate two different catalytic cycles in a one-pot system. This Cu-catalyzed method is compatible with a great variety of functional groups, likely owing to using di-tert-butyl peroxide as a mild oxidant and having no need for any acid or base additive, as exhibited by the terminal alkenes bearing reactive organosilicon groups that participate in the regioselective α-allylation of carbonyl compounds to exclusively construct a number of alkenyl-silane nucleophiles. This Cu–BINAP catalytic system also enables the synthesis of 2,3-dihydrofurans through the reactions of ketones with 1,1-disubstituted alkenes.