Structural diversity of tetranuclear tungsten sulfide clusters: syntheses and crystal structures of clusters containing raft-type W4(μ3-S)2(μ-S)4 and tetrahedral W4(μ-S)6 cores

Synthesis, Structure, and Properties of Molybdenum and Tungsten Cyano Complexes with Cuboidal M4(μ3-E)4 (M = Mo, W; E = S, Se, Te) Cores

“…Homometallic Mo 4 S 4 cuboidal clusters of general formula [Mo 4 S 4 L 12 ], with ligands L either neutral or anionic, have been known for some 20 years. ,− ,,,, The oxidation states of molybdenum vary from III to V. Cuboidal-type molecular clusters with Mo 4 Se 4 n + cores ( n = 4, 5, 6) have also been reported. , As compared with molybdenum the number of W 4 chalcogenide complexes is limited; examples are (a) the raft- type complex [W 4 S 6 (SH) 2 (PMe 2 Ph) 6 ], , (b) the tetrahedral complex [W 4 S 6 (PMe 2 Ph) 4 ] with a W 4 (μ 2 -S) 6 adamantane-like core, , (c) [W 4 S 8 (H 2 NCH 2 CH 2 NH 2 ) 4 ]S having a cuboidal W 4 S 4 10+ core, (d) the W(V) complex {W(NC 6 H 4 CH 3 )(S 2 P(OC 2 H 5 ) 2 (μ 3 -S)} 4 , which in solution is formed by an associative equilibrium of two dimers, and (e) β-[W 4 S 4 (μ-dtp) 2 (dtp) 4 ] and α-[W 4 S 4 (μ-dtp) 3 (dtp) 3 ] with cuboidal-type W 4 S 4 6+ cores (dtp = dithiaphosphate)…”

“…1,[3][4][5][6]8,9,15,16 The oxidation states of molybdenum vary from III to V. Cuboidal-type molecular clusters with Mo 4 Se 4 n+ cores (n ) 4, 5, 6) have also been reported. 17,18 As compared with molybdenum the number of W 4 chalcogenide complexes is limited; examples are (a) the raft- type complex [W 4 S 6 (SH) 2 (PMe 2 Ph) 6 ], 19,20 (b) the tetrahedral complex [W 4 S 6 (PMe 2 Ph) 4 ] with a W 4 (µ 2 -S) 6 adamantane-like core, 19,20 (c) [W 4 S 8 (H 2 NCH 2 CH 2 NH 2 ) 4 ]S having a cuboidal W 4 S 4 10+ core, 21 (d) the W(V) complex {W(NC 6 H 4 CH 3 )(S 2 P-(OC 2 H 5 ) 2 (µ 3 -S)} 4 , which in solution is formed by an associative equilibrium of two dimers, 22 and (e) β-[W 4 S 4 (µ-dtp) 2 (dtp) 4 ] and R-[W 4 S 4 (µ-dtp) 3 (dtp) 3 ] with cuboidal-type W 4 S 4 6+ cores (dtp ) dithiaphosphate). 23 Solid-state molybdenum compounds Mo 4 S 4 X 4 (X ) Cl, Br, I) and M′Mo 4 E 8 (M′ ) Al, Ga, E ) S; M′ ) Ga, E ) Se) are known to contain [Mo 4 E 4 ] cores, with each Mo octahedrally coordinated by three chalcogen and three halogen atoms, or six chalcogen atoms.…”

Aggregation of PMe3-Stabilized Molybdenum Sulfides and the Catalytic Dehydrogenation of H2S

“…The 1 H and 31 P NMR signals match those observed in 5H . A derivative of this species, W 4 (μ 2 -S) 4 (μ 3 -S) 2 (PMe 2 Ph) 6 (SH) 2 , had been previously synthesized via treatment of W(N 2 ) 2 (PMe 2 Ph) 4 with (Me 3 Si) 2 S and MeOH, conditions conducive to in situ formation of H 2 S. Previous workers did not detect the S H signals in the 1 H NMR spectrum for W 4 (μ 2 -S) 4 (μ 3 -S) 2 (PMe 2 Ph) 6 (SH) 2 .…”

A Model for Protonation of Dinitrogen by Nitrogenase: Protonation of Coordinated Dinitrogen on Tungsten with Hydrosulfido-Bridged Dinuclear Complexes1

“…Up until now, many mononuclear and polynuclear N 2 complexes of transition metals have been prepared, some of which liberate NH 3 and/or hydrazine (NH 2 NH 2 ) by protonolysis with inorganic acids such as H 2 SO 4 . Typically, molybdenum and tungsten N 2 complexes of the type M(N 2 ) 2 (PMe 2 Ph) 4 (M = Mo, W) produce NH 3 and/or NH 2 NH 2 in good yields by treatment with inorganic acids. 5a, Previously, the reactions of organic thiols or H 2 S with those N 2 complexes were investigated, where H 2 gas was evolved and no N−H bond formation was observed. , This indicates that organic thiols and H 2 S attack the electron-rich metal center in the N 2 complexes in place of the coordinated N 2 . Very recently, we have reported the formation of NH 3 by ruthenium-assisted protonation of N 2 on W atom with H 2 under mild conditions .…”

“…5a,6 Previously, the reactions of organic thiols or H 2 S with those N 2 complexes were investigated, where H 2 gas was evolved and no N-H bond formation was observed. 7,8 This indicates that organic thiols and H 2 S attack the electron-rich metal center in the N 2 complexes in place of the coordinated N 2 . Very recently, we have reported the formation of NH 3 by ruthenium-assisted protonation of N 2 on W atom with H 2 under mild conditions.…”