We report palladium-catalyzed intermolecular carboacylation of alkenes with ester electrophiles and tetraarylborate nucleophiles. Bicyclic alkenes react with a variety of pentafluorophenyl benzoate and alkanoate esters and sodium tetraarylborates to form ketone products in ≤99% yields. These reactions occur in the absence of a directing group and demonstrate esters are competent acyl electrophiles for intermolecular alkene carboacylation reactions.

We report Ni-catalyzed dearylative cyclocondensation of aldehydes, alkynes, and triphenylborane. The reaction is initiated by oxidative cyclization of the aldehyde and alkyne coupling partners to generate an oxanickelacyclopentene which reacts...

Computational and mechanistic studies of Pd-catalyzed alkene carboacylation via ester bond activation are investigated through a combination of density functional theory (DFT) and second order perturbation theory (MP2) calculations and experimental methods. The key elementary steps of the catalytic cycle, oxidative addition, migratory insertion, transmetalation, and reductive elimination, are examined. In this paper, we propose a novel mechanism for the title carboacylation reaction; the calculations indicate that the Pd­(II) intermediate preceding migratory insertion is a cationic intermediate as opposed to the neutral metal intermediate species previously proposed in these types of reactions. In addition, a new organoboron species has been identified as a competent nucleophile in this transition metal-catalyzed reaction. Analysis of competing Suzuki coupling pathways reveals the carboacylation pathway to be more energetically favorable with the appropriate selection of arylboron reagent. Experimental control studies are consistent with the computational findings.