Gonzálvez, Miguel A.Williams, Craig M.Martínez López, Manuel, 1957-Bernhardt, Paul V.2023-03-232024-03-062023-03-060020-1669https://hdl.handle.net/2445/195844Organocopper(II) reagents are an unexplored frontier of copper catalysis. Despite being proposed as reactive intermediates, an understanding of the stability and reactivity of the CuII-C bond has remained elusive. Two main pathways can be considered for the cleavage mode of a CuII-C bond: homolysis and heterolysis. We recently showed how organocopper(II) reagents can react with alkenes via radical addition, a homolytic pathway. In this work, the decomposition of the complex [CuIILR]+ [L = tris(2- dimethylaminoethyl)amine, Me6tren, R = NCCH2-] in the absence and presence of an initiator (RX, X = Cl, Br) was evaluated. When no initiator was present, first-order CuII-C bond homolysis occurred producing [CuIL]+ and succinonitrile, via radical termination. When an excess of the initiator was present, a subsequent formation of [CuIILX]+ via a second-order reaction was found, which results from the reaction of [CuIL]+ with RX following homolysis. However, when Brønsted acids (R′-OH: R′ = H, Me, Ph, PhCO) were present, heterolytic cleavage of the CuII-C bond produced [CuIIL(OR′)]+ and MeCN. Kinetic studies were undertaken to obtain the thermal (ΔH⧧, ΔS⧧) and pressure (ΔV⧧) activation parameters and deuterium kinetic isotopic effects, which provided an understanding of the strength of the CuII-C bond and the nature of the transition state for the reactions involved. These results reveal possible reaction pathways for organocopper(II) complexes relevant to their applications as catalysts in C-C bond forming reactions.25 p.application/pdfeng(c) American Chemical Society , 2023Reaccions químiquesCinètica químicaChemical reactionsChemical kineticsinfo:eu-repo/semantics/article7328442023-03-23info:eu-repo/semantics/openAccess