Synthesis, Structure, and Applications of Transition-Metal Polyhydride Anions

Article abstract of DOI:10.1021/ja00204a010

KH is used to deprotonate ReH7L2 (L = PMe2Ph, PMePh2, and PPh3) and ReH5P3 and WH6P3 (P = PMe2Ph) in THF, and the resulting anions are characterized by variable-temperature multinuclear NMR.The solid-state structure of K(THF)2ReH6(PPh3)2 was determined by X-ray diffraction and revealed a centrosymmetric dimer connected by bridging hydrogen atoms as follows: <<(Ph3P)2ReH3>(μ-H)>2(μ3-H)4.Crystallographic data (213 K): a = 10.987(2), b = 27.134(4), c = 14.030(2) Angstroem; β = 96.609(13) deg; V = 4154.6(11) Angstroem³, and Z = 2 in space group P2₁/n.The reaction of KD with ReH7(PPh3)2 gave HD and ReH6(PPh3)2(-), thus supporting the idea that the synthetic reaction is in fact proton transfer and ruling out a mechanism consisting of addition of KD to unsaturated ReH5(PPh3)2.LiRuH3(PPh3)3 reacts with 1/2 <(COD)RhCl>2 to give (COD)Rh(μ-H)3Ru(PPh3)3 as the kinetic product; this then rearranges (t_1/2 = 40 min) in solution to give the thermodynamic isomer (COD)RhH(μ-H)Ru(H)(PPh3)3.