Unimolecular Reactions of Organocuprates and Organoargentates

The gas-phase fragmentation reactions of the group 11 organometallates CH 3 MR − (R = CH 3 CH 2, CH 3 CH 2 CH 2, (CH 3 ) 2 CH, (CH 3 ) 3 C, CH 2 CHCH 2, PhCH 2, Ph, M = Cu, Ag) and CH 3 CH 2 CuCH 2 CH 3 − were studied by density functional theory (DFT) calculations and, for those accessible in the gas phase, via collision-induced dissociation (CID) and selected deuterium labeling experiments. The mixed metallates CH 3 MR − were found to fragment via a diverse set of pathways, including bond homolysis, bond heterolysis, and β-hydride elimination. A 1,2-dyotropic rearrangement was observed for R = Ph. DFT calculations suggest that the M−C bond energy, the availability of metal orbitals for π-bonding, and the nature of the ligand R group substituents are the main factors that control the observed reactivity. Comparisons with the known solution-phase reactivity of organocopper and organosilver species are made.