Nickel(II) Dihydrogen and Hydride Complexes as the Intermediates of H<sub>2</sub> Heterolytic Splitting by Nickel Diazadiphosphacyclooctane Complexes
Nikolay V. Kireev, Alexey S. Kiryutin, Alexander A. Pavlov, Alexandra V. Yurkovskaya, Elvira I. Musina, Andrey A. Karasik, Elena S. Shubina, Konstantin L. Ivanov, Natalia V. Belkova
Abstract
Abstract The interaction of a series of [Ni(P R1 2 N R2 2 ) 2 ] 2+ complexes 1 – 4 (where P R1 2 N R2 2 =1,5‐R 2 ‐3,7‐R 1 ‐1,5‐diaza‐3,7‐diphosphacyclooctane; R 1 = o‐ Py, Ph; R 2 =CHPh 2 , p‐ Tol) with H 2 is reversible yielding the products of heterolytic splitting of dihydrogen in the metal coordination sphere ‐ [NiH(P R1 2 N R2 2 )(P R1 2 N R2 2 H)] 2+ . Experiments conducted with parahydrogen allowed to see the signal at about −4 ppm corresponding to the metal‐bound H 2 in the nickel dihydrogen complex [Ni(η 2 −H 2 )(P Ph 2 N CHPh2 2 ) 2 ] 2+ ( 3‐H 2 ) – the short‐living non‐classical intermediate, which so far has been revealed only computationally.