Mono- and dihydrido-bridged tungsten-platinum complexes

Effect of Solvent in the Reaction of Cp2ZrH{(μ-H)2BR2} (R2 = C4H8, C8H14) with B(C6F5)3: Formation of [HB(C6F5)3]- Salts of the Unsupported Hydrogen-Bridged Cations [(μ-H){Cp2Zr(μ-H)2BR2}2]+ (R2 = C4H8, C8H14) and [Cp2Zr(OEt

“…To our knowledge these are the first examples of unsupported M−H−M hydrogen-bridged bonds of group IV 10-15 even though numerous complexes containing three-center two-electron M−H−M bonds of groups V, VI, VII, and VIII 14 are well known. The Zr−H−Zr bond is bent, consistent with previously reported M−H−M bonds, with the exception of the Ru−H−Ru bond in {Ru 2 H(μ-H)Cl( syn -Me 4 [14]aneS 4 ) 2 }Cl. 14b,d The angle of Zr−H−Zr is 163(2)° for 3 and 164(2)° for 4 , and the Zr···Zr distance is 3.8983(9) Å for 3 and 3.9755(4) Å for 4 . A noteworthy feature of both structures is that the Zr···Zr distance is 0.2−0.3 Å longer than the sum [2radii Zr(cov) + 2radii H(cov)] = 3.70 Å for a bond angle of about 164° .…”

Hydride Transfer to Gold: Yes or No? Exploring the Unexpected Versatility of Au⋅⋅⋅H−M Bonding in Heterobimetallic Dihydrides

“…To test this, the reactivity of well-defined cationic Au(I) and Au(III) species with Cp2WH2 was compared with that of Cp2ZrH2; these metal dihydrides possess closely comparable M-H bond energies (bond dissociation enthalpies: Cp*2ZrH2 339 kJ/mol; Cp2WH2 311±4 kJ/mol) but different electron configurations. [30] Both metallocene dihydrides are known to form heterometallic compounds with bridging hydride interactions: Cp2ZrH2 gives stable adducts with Mg, Zn and Al hydrides, [31] while Cp2WH2 has been extensively explored in combination with many cationic late metal centers, including Al, [32] Rh, [33] Pt [34] and rare earth metals. [35] Cp2WH2 is also a good ligand for isolated Cu and Ag centers, [36] while to our knowledge there is no precedent for W-Au dihydrides.…”

Reactions of diphenylpyridylphosphine with H2Os3(CO)10 and H4Ru4(CO)12, P–C bond splitting in the coordinated ligand and isolation of the oxidative addition products

“…Intermediacy of the species of this sort is a common point of the mechanistic schemes describing stoichiometric reductive elimination and related catalytic processes. ThatÕs why considerable attention has been already paid to investigation of this chemistry and structural characterization of the isolable species, which belong to the family of mono-and binuclear transition metal complexes [22,24,[33][34][35][36][37][38]. However, 1 is the first example of cluster molecule containing cis-(R-M-H) fragment, which is stable in the solid state and solution under ambient conditions.…”

“…On the contrary, a series of mono-and binuclear transition metal complexes containing hydride and alkyl (aryl) ligands were isolated and studied in detail because of their importance for understanding the mechanisms of catalytic activation of the hydrocarbon C-H bond, see for example [21][22][23][24][25][26][27][28][29][30][31][32]. Some particularly stable cis ''hydride-aryl'' complexes of ruthenium [33], iridium [34][35][36], platinumtungsten [37] dimers, [Me 2 Si]-ansa-bridged permethylmetallocene systems [22,24,38] allowed X-ray crystallographic study. In the present paper we report the H 2 Os 3 (CO) 10 and H 4 Ru 4 (CO) 12 reactions with diphenylpyridylphosphine under various conditions and structural characterization of four novel products formed in these reactions.…”