Metal kinetic hydricity

Thermochemical studies of acidity and hydricity are extremely valuable, since they can help determine the energies of potential intermediates in catalytic cycles, and can thus guide the choice of complexes proposed as catalysts. But, since catalysis is a kinetic phenomenon, the kinetics of delivery of a proton or hydride are also important. The kinetics of proton transfer from metal hydrides to amines [21] or metal alkynyl complexes [22], as well as degenerate proton transfers between metal hydrides and metal anions [21] led to the conclusion that proton transfers from metal hydrides have a high intrinsic barrier. 

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