Synthesis of a Sulfido-Capped Trinuclear Cluster [{(η⁵-C₅Me₅)Ir}₂{Mo(CO)₃}(μ₃-S)₂] and Its Reactions at the Molybdenum Site Forming a Series of Ir₂MoS₂ Clusters

Abstract

Treatment of a hydrosulfido-bridged diiridium complex, [(Cp*IrCl) 2 (µ-SH) 2 ] (1; Cp* ) η 5 -C 5 Me 5 ), with [Mo(η 6 -toluene)(CO) 3 ] in the presence of NEt 3 gave the sulfido-bridged Ir 2 Mo cluster [(Cp*Ir) 2 -{Mo(CO) 3 }(µ 3 -S) 2 ] (3). Detailed studies on the reactivity of its Mo site have resulted in the isolation of a series of new Ir 2 Mo(µ 3 -S) 2 clusters. Thus, 3 reacted with Ph 2 PCH 2 CH 2 PPh 2 (dppe) to afford [(Cp*Ir) 2 -{Mo(CO)(dppe)}(µ 3 -S) 2 ] (4), which underwent the oxidation by I 2 at the molybdenum site to give [(Cp*Ir) 2 -{MoI(CO)(dppe)}(µ 3 -S) 2 ]I (5). On the other hand, oxidation of 3 with [Cp 2 Fe][PF 6 ] in THF-MeCN resulted in the elimination of one CO ligand and concomitant coordination of two MeCN molecules at the Mo center, yielding [(Cp*Ir) 2 {Mo(CO) 2 (MeCN) 2 }(µ 3 -S) 2 ][PF 6 ] 2 (6). Further oxidation of 6 using O 2 gas led to the elimination of all the remaining CO ligands to give an oxo-dichloro cluster, [(Cp*Ir) 2 -(MoOCl 2 )(µ 3 -S) 2 ] (7). The ligation of diphosphines to the molybdenum site in 7 formed the cationic oxo-chloro cluster [(Cp*Ir) with concurrent dissociation of one of the Cl ligands, and the following deoxygenation from 8a with BCl 3 gave [(Cp*Ir) 2 {MoCl 3 (dmpe)}(µ 3 -S) 2 ][BCl 4 ] (9). Reduction of 9 with Cp 2 Co afforded a paramagnetic Mo(III) cluster, [(Cp*Ir) 2 {MoCl 2 (dmpe)}(µ 3 -S) 2 ][BCl 4 ] (11), whereas reduction of 8c with NaBH 4 resulted in the formation of a Mo(II) dihydrido cluster, [(Cp*Ir) 2 {MoH 2 -(dppe)}(µ 3 -S) 2 ] (12). X-ray analyses have been undertaken to determine the detailed structures for 3, 4,

Properties and Reactivities of the Hydrido Ligands in Iridium Sulfido Clusters Relevant to Activation and Production of H2

“…Our recent research has focused on syntheses of transition-metal sulfido clusters and exploration of their reactivities to activate small molecules effectively. – For the systems using metal sulfido clusters, it may be expected that reaction proceeds with retention of their multimetallic core structures even under relatively forcing conditions, owing to the presence of firmly bonded sulfido bridges. In this paper, we wish to describe the structures and reactivities of a series of new Ir sulfido clusters having hydrido ligands, which have been synthesized from the reactions of the Ir hydrido complex [(Cp*Ir) 2 (μ-H) 3 ][BF 4 ] ( 1 ; Cp* = η 5 -C 5 Me 5 ) with controlled amount of the sulfido source.…”

Organometallic chemistry of bi- and poly-metallic complexes

“…126 The reactivity of the sulfido-capped trinuclear complex 30 at the molybdenum site has been investigated resulting in the formation of several novel Ir 2 MoS 2 clusters via processes such as ligand exchange, oxidation and reduction. 127 The C 2 carbide cluster complex [(m 4 -CQC)Ru 2 (FeCp*) 2 (CO) 10 ] (Cp*QC 5 Me 5 ) has been found to support a variety of reactions with alkynes including C-C coupling and oxidative metalacyclisation. The labile complex [(m 4 -CQC)Ru 2 -(FeCp*) 2 (CO) 8 (NCMe) 2 ] has been found to undergo the same reactions but under milder reactions conditions.…”

Assembly and Redox-Rich Hydride Chemistry of an Asymmetric Mo2S2 Platform

“…A number of molecular analogues for the surface interface of MoS x materials have been shown to be active HER catalysts, although Mo-H intermediates, if they are formed, have not been well-characterized [15][16][17][18][19][20][21][22]. Indeed, molecular Mo-H complexes featuring sulfur-donor ligands, particularly sulfides, are uncommon [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]. Consequently, we have been interested in preparing molybdenum-hydride complexes with sulfide ligands and studying their chemistry and spectroscopy.…”