73690-53-6Relevant academic research and scientific papers
Reversible hydrogen adsorption at room temperature using a molybdenum-dihydrogen complex in the solid state
Uchida, Kaiji,Kishimoto, Naoki,Noro, Shin-Ichiro,Iguchi, Hiroaki,Takaishi, Shinya
supporting information, p. 12630 - 12634 (2021/09/28)
Reversible H2storage under mild conditions is one of the most important targets in the field of materials chemistry. Dihydrogen complexes are attractive materials for this target because they possess moderate adsorption enthalpy as well as adsorption without cleavage of the H-H bond. In spite of these advantages, H2adsorption studies of dihydrogen complexes in the solid state are scarce. We herein present H2adsorption properties of the 16-electron precursor complex ([Mo(PCy3)2(CO)3]) in the solid state synthesized by two procedures. One is the direct synthesis under an Ar atmosphere (1), and the other is removal of the N2-adduct under vacuum (2).2showed ideal Langmuir type reversible ad/desorption of H2above room temperature, whereas1showed irreversible adsorption. The adsorption enthalpy of2was larger than that in THF solution. Using DFT calculation, this difference was explained by the absence of the agostic interaction in the solid state.
Molecular Hydrogen Complexes of the Transition Metals. 4. Preparation and Characterization of M(CO)3(PR3)2(η2-H2)(M = Mo, W) and Evidence for Equilibrium Dissociation of the H-H bond To Give MH2(CO)3(PR3)2
Kubas, Gregory J.,Unkefer, Clifford J.,Swanson, Basil I.,Fukushima, Eiichi
, p. 7000 - 7009 (2007/10/02)
The syntheses, properties, and spectral characterization of the first examples of molecular hydrogen complexes, M(CO)3(PR3)2(H2) (M = Mo, W; R3 = Cy3, i-Pr3, Cy2-i-Pr), are reported in full.All six of the expected fundamental vibrational modes for η2-H2 binding, including ν(HH) at 2690 cm-1, have been located.The hydrogen atoms of the H2 ligand, but not of the phosphines, undergo exchange with D2 to give HD, even in the solid state.Solid-state 2H NMR of W(CO)3(P-i-Pr3)2(D2) shows rapid rotation of the D2 about the metal-D2 axis.IR and variable-temperature 1H and 31P NMR of solutions of the H2 complexes reveal the presence of equilibrium amounts (10-30percent) of a species that the data indicate is a 7-coordinate dihydride, MH2(CO)3(PR3)2.The latter is presumably formed by dissociation of the H-H bond, thus completing oxidative addition of H2 to the metal.The dihydride is fluctional, but low-temperature NMR spectroscopy shows that both the hydride and phosphorus ligands are inequivalent.At -80 deg C the T1 value for the 1H NMR signal of the H2 ligand is 0.004 s, almost three orders of magnitude less than that of the hydride protons (1.7 s) in WH2(CO)3(P-i-Pr3)2.
Five-co-ordinate Molybdenum and Tungsten Complexes, , which Reversibly add Dinitrogen, Dihydrogen, and Other Small Molecules
Kubas, Gregory J.
, p. 61 - 62 (2007/10/02)
New complexes of molybdenum and tungsten with dinitrogen and other small molecules, trans- (L = N2, H2, C2H4, or SO2), have been synthesized by the reaction of with 2PCy3 in the presence of L; removal of L yield
