Regio- and stereoselective allylic trifluoromethylation and fluorination using CuCF3 and CuF reagents.

Copper-mediated trifluoromethylation of allylic chlorides and trifluoroacetates was performed using a convenient Cu-CF3 reagent. The reaction is suitable for selective synthesis of allyl trifluoromethyl species. Mechanistic studies indicate that the reaction proceeds via a nucleophilic substitution mechanism involving allyl copper intermediates.

Mechanistic investigation of the palladium-catalyzed synthesis of allylic silanes and boronates from allylic alcohols.

The mechanism of the palladium-catalyzed synthesis of allylic silanes and boronates from allylic alcohols was investigated. (1)H, (29)Si, (19)F, and (11)B NMR spectroscopy was used to reveal key intermediates and byproducts of the silylation reaction. The tetrafluoroborate counterion of the palladium catalyst is proposed to play an important role in both catalyst activation as well as the transmetalation step.

Palladium-catalyzed oxidative allylic C-H silylation.

Palladium-catalyzed allylic C-H silylation was performed with use of hexamethyldisilane as the silyl source. These C-H functionalization reactions occur only in the presence of hypervalent iodine reagents or other strong oxidants and proceed with excellent regioselectivity, providing the linear allylic isomer of the allylsilane products. In demonstrating the first oxidative allylic C-H silylation of alkenes, this study marks an important advance for the catalytic C-H functionalization method.

Pincer complex-catalyzed redox coupling of alkenes with iodonium salts via presumed palladium(IV) intermediates.

Palladium pincer complexes directly catalyze the redox coupling reactions of functionalized alkenes and iodonium salts. The catalytic process, which is suitable for mild catalytic functionalization of allylic acetates and electron-rich alkenes, probably occurs through Pd(IV) intermediates. Due to the strong metal-ligand interactions, the oxidation of phosphine and amine ligands of the pincer complexes can be avoided in the presented reactions.