How to achieve a successful Heck--Matsuda reaction based nickel complexes: Theoretical investigation of mechanistic insights aiming potencial experimental conditions and reagents

The catalytic cycles proposed for a Heck--Matsuda reaction mediated by nickel complexes occurring via a closed shell singlet Ni(0)/Ni(II) or via an open shell doublet Ni(I)/Ni(III) were obtained, as well as a thermodynamic analysis of its pre-catalysis. The energy span analysis from the kinetic energy profile for the singlet Ni(0)/Ni(II) cycle indicated variation of the rate--determining states according to the rotation flexibility of the starting olefin in the b-hydride elimination and/or the strength of the base applied in the reductive elimination step. The turnover frequency (TOF) calculation from the theoretical data presented good proximity with the value calculated from literature experimental success. Thermodynamic profile of the pre-catalysis pointed out to favored doublet catalytic cycle mechanism front to the singlet one if an aryl radical species is present in the reaction medium.