Dihydrogen-Bond-Promoted Catalysis:  Catalytic Hydration of Nitriles with the Indenylruthenium Hydride Complex (η⁵-C₉H₇)Ru(dppm)H (dppm = Bis(diphenylphosphino)methane)

Abstract

The indenylruthenium hydride complex (eta(5)-C(9)H(7))Ru(dppm)H was found to be active in catalyzing the hydration of nitriles to amides. The chloro analogue (eta(5)-C(9)H(7))Ru(dppm)Cl was, however, found to be inactive. Density functional theory calculations at the B3LYP level provide explanations for the effectiveness of the hydride complex and the ineffectiveness of the chloro complex in the catalysis. It is learned that the presence of a Ru-H.H-OH dihydrogen-bonding interaction in the transition state lowers the reaction barrier in the case of (eta(5)-C(9)H(7))Ru(dppm)H, but in the chloro system, the corresponding transition state does not contain this type of interaction and the reaction barrier is much higher. A similar dihydrogen-bond-promoting effect is believed to be responsible for the catalytic activity of the hydrotris(pyrazolyl)borato (Tp) ruthenium complex TpRu(PPh(3))(CH(3)CN)H in CH(3)CN hydration. The chloro analogue TpRu(PPh(3))(CH(3)CN)Cl shows no catalytic activity.

Rhenium(VII) polyhydrides supported by chelatingbis-phosphine ligands: DPEphos, xantphos and biphep

“…These complexes have been implicated as intermediates in a variety of reactions, such as hydrogenation and hydroformylation [12][13][14][15], and can be found in biological systems, such as nickel-dependent hydrogenase enzymes [16], and in industry [17]. The discovery of the dihydrogen bond (M-H Á Á Á H-X, where M ¼ transition metal or boron; X ¼ N, O, F) has reinvigorated the field of hydride chemistry [4,5].…”

Regulating function of methyl group on the strength of dihydrogen bond in HBeH-HCCH and HMgH-HCCH complexes

“…It has *Corresponding author. E-mail: liqingzhong1990@sina.com been demonstrated that dihydrogen bonds can influence structure, reactivity, and selectivity in solution and solid state [1,14,15], thus having potential utility in catalysis [16,17], crystal engineering and materials chemistry [18].…”

Is a MH (M = Be and Mg) radical a better electron donor in halogen‐hydride interaction?: A theoretical comparison with HMH

“…The role of negatively charged hydrogen was also found in the so‐called charge‐inverted hydrogen bonds32, 33 and hydride bonds 34. This means that the halogen‐hydride interaction has similar roles in stabilizing metal complexes,35 controlling reactivity and selectivity of chemical reactions,36 promoting catalytic reactions,37 and mediating proton transfer38 like dihydrogen bonds. This interaction is rare, although it was found in the Cambridge Structural Database 25.…”