Hydrido complexe

First hydrido complex of a transition metal prepared by W. Hieber and F. Leutert. 

Complexes with chelating polysulfidc ligands can be made either by reacting complex metal halides with. solutions of polysulfides or by reacting hydrido complexes with elemental... 

Hydrido complexes are well-known bui simple binary hydrides are noi. which is iti keeping wiih ihe posinon nf ihese melals in Ihe hydrogen gap" portion of ihe periodic lable ip, 67. ... 

Hydrido complexes of all three elements, and covering a range of formal oxidation states, are important because of their roles in homogeneous catalysis either as the catalysts themselves or as intermediates in the catalytic cycles. 

Despite the above similarities, many differences between the members of this triad are also to be noted. Reduction of a trivalent compound, which yields a divalent compound in the case of cobalt, rarely does so for the heavier elements where the metal, univalent compounds, or hydrido complexes are the more usual products. Rhodium forms the quite stable, yellow [Rh(H20)6] " ion when hydrous Rh203 is dissolved in mineral acid, and it occurs in the solid state in salts such as the perchlorate, sulfate and alums. [Ir(H20)6] + is less readily obtained but has been shown to occur in solutions of in cone HCIO4. 

Tetraphenylmolybdenocene dihydride Mo(r 5-C5HPh4)CpH2 (45) was formed by addition of diphenylacetylene to MoCpL(PhC CPh)CH3 (L = P(OMe)3) (Eq. 15), presumably via an ot-hydrogen abstraction to an intermediate methylidene hydrido complex, followed by addition of two equivalents of diphenylacetylene and C — H insertion with concomitant elimination of L [57 b],... 

Monometal hydrido-complexes of transition metals. G. L. Soloveichik and B. M. Bulychev, Russ. Chem. Rev. (Engl. Transl.), 1982,51,286-302 (160). 

Hydrido complexes of rhenium synthesis and reactivity, D. Giusto, Inorg. Chim. Acta, Rev., 1972, 6,91-101(61). 

These reactions give products similar to those described in 8.3.2.1. Transition-mclal hydrido complexes react with a halogen derivative of a group-IB metal to form a hydrogen halide and the required metal-metal bond ... 

Fe(0)(CO)s HgCl2 + HgCl2 Fe(II)(CO)4(HgCl)2 + COCI2 (f) A similar reaction not involving oxidation is that of a hydrido complex with HgCl2... 

After graduating from Mikunigaoka High School, Osaka, he studied chemistry at the University of Tokyo from 1968 to 1972 and continued research on hydrido complexes and transition metal hydrides to earn the Dr. sc. degree under the supervision of Professor Yukiyoshi Sasaki in 1977. As a postdoctoral fellow, he worked with Professor John D. Corbett at the Ames Laboratory from 1977 to 1979, and with Professor Arndt Simon at Max-Planck-Institut fur Festkorperforschung, Stuttgart, Germany from 1979 to 1981. In... 

Yoshida and Otsuka found that platinum(O) complexes [PtLj] (26) (a L = PEtj b L = P Prj) and rhodium hydrido complexes such as [RhHLj] (L = P Prs 33, PEts), [RhiHidr-NJlPCyslJ (34), tram-[RhH(N2)(PPh Bu2)J, and [RhH(P Bu3)J, all of which carry electron-donating alkylphosphine ligands, can catalyze the water gas shift reaction under fairly mild conditions (100-150°C CO 20 kg/cm ) (Eq. 6.32) [23, 60]. Among these complexes, [RhH(P Pr3)3] (33) was the most active catalyst precursor. Several complexes were isolated from or detected in the reaction mixture... 

The second method is the more general one. The choice of the base depends on the acidity of the hydrido complexes. In most cases KH, NaH or LinBu are very suitable. For the more acidic complexes, amines are also convenient. Complexes of low acidity were successfully deprotonated by KH/18-crown-6. 

When irradiated in the presence of norbornadiene and high-pressure synthesis gas, rhodium chloride is converted to a catalyst which is active for a variety of reactions. /2A/. The salt is probably converted photochemically to the rhodium norbornadiene complex 9. This dimer may undergo a consecutive photoreaction to give the monomeric hydrido complex 10, which is the actual catalyst for polymerisation, hydrogenation, and hydroformylation reactions. 

Polymeric films of [(//5-C s Me5)M(L)Cl]+complexes (M = Ir, Rh L = pyrrole-substituted bpy or phen) have been coated on an electrode by oxidative electropolymerization. The buildup of hydrido complexes in films is well known 27,28,30 the high electrocatalytic activity of these molecular electrode materials towards dihydrogen evolution in organic and aqueous electrolytes is also well known.25,31 For example, H2 is evolved at —0.55 V vs. SCE at a poly [(j75-C5Me5)-Rh(bpy)Cl]+ film in pH 1 aqueous solution.31... 

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