On the Synthesis and Chemical Behaviour of the Elusive Bis(hydrosulfido)‐Bridged Dinuclear Rhodium(I) Complexes [{Rh(μ‐SH)(CO)(PR₃)}₂]

Hydride Mobility in Trinuclear Sulfido Clusters with the Core [Rh3(μ‐H)(μ3‐S)2]: Molecular Models for Hydrogen Migration on Metal Sulfide Hydrotreating Catalysts

“…[Rh(µ-SH){P(OPh) 3 } 2 ] 2 and [Rh(µ-SH)(CO)(PPh 3 )] 2 were prepared following the synthetic procedure recently described. [18] Synthesis of [Rh 3 (100 µL, 0.719 mmol, ρ = 0.728 g mL -1 ) were reacted in benzene (3 mL), following the procedure described for compound 2, to give a dark red solution in 2 hours. The solvent was evaporated under vacuum and the residue dissolved in CH 2 Cl 2 (1 mL).…”

“…A similar pattern for the Rh-S bond distances has been observed in the closely related cluster, [Rh 3 (µ-H)(µ 3 -S) 2 (CO) 3 (PCy 3 ) 3 ], where also two types of bond lengths -all slightly longer in the latter case-has been reported (2.366 and 2.334(2) Å). [18] The main differences between both cluster molecules involve the presence of a bridging hydride ligand, which has been included in the model from electrostatic potential energy calculations. [21] In both cases the hydride occupies a nearly coplanar position with the plane defined by the three metals but, as inferred from NMR measurements, while in 1 it is located Jiménez, Lahoz, Lukešová, Miranda, Modrego, Nguyen, Oro and Pérez-Torrente, manuscript Kinetic study for the hydride exchange in trinuclear hydrido-sulfido clusters by 2D-EXSY spectroscopy.…”

“…[18] In contrast with [Rh(µ-SH){P(OPh) 3 } 2 ] 2 , the complexes [Rh(µ-SH)(CO)(PR 3 )] 2 slowly transform in solution into the 48-electron trinuclear hydrido-sulfido clusters [Rh 3 (µ-H)(µ 3 -S) 2 (CO) 3 (PR 3 ) 3 ] (R = Cy, Ph) with the release of H 2 S(g) in a reversible way. Related precedent in this chemistry are the clusters [M 3 (µ-H)(µ 3 -S) 2 (cod) 3 ] that are formed by reaction of complexes [M(µ-Cl)(cod)] 2 with NaSH, [19] or [M(acac)(cod)] and [M(µ-OMe)(cod)] 2 (M = Rh, Ir) with H 2 S(g).…”

“…[18] The clean synthesis of trinuclear hydrido-sulfido clusters from [Rh(µ-SH) by a intramolecular proton transfer.…”

Bis(hydrosulfido)-bridged dinuclear rhodium(i) complexes as a platform for the synthesis of trinuclear sulfido aggregates with the core [MRh2(μ3-S2)] (M = Rh, Ir, Pd, Pt, Ru)

“…The 48-valence-electron clusters can be described as composed by two metal-metal bonded 16-electron M II metal atoms, with square-pyramidal geometries due 35 to the coordination to the bridging hydride ligand, and a 16-electron square-planar M I centre. 14,15 The formation of the core [MRh 2 (µ-H)(µ 3 -S) 2 ] is a consequence of the deprotonation of a hydrosulfido ligand in the presence of d 8 metal fragments to give the trinuclear hydrosulfido-sulfido intermediates with the core 40 [MRh 2 (µ 3 -SH)(µ 3 -S)] that collapse to the hydrido-sulfido clusters by a intramolecular proton transfer (pathway i, Scheme 1). Alternatively, the deprotonation of both hydrosulfido ligands should result in the formation of the anionic [Rh 2 (1).…”