title: A family of oxo-chalcogenide molybdenum and tungsten complexes, (n-Bu4N)2[M2O2(mu-Q)2(1,3-dithiole-2-thione-4,5-dithiolate)2] (M = Mo, W; Q = S, Se): new synthetic entries, structure, and gas-phase behavior.
abstract: A new series of complexes with the general formula (n-Bu4N)2[M2O2(micro-Q)2(dmit)2] (where M = Mo, W; Q = S, Se; dmit = 1,3-dithiole-2-thione-4,5-dithiolate) have been prepared. Fragmentation of the trinuclear cluster (n-Bu4N)2[Mo3(micro3-S)(micro-S2)3(dmit)3] in the presence of triphenylphosphine (PPh3) gives the dinuclear compound (n-Bu4N)2[Mo2O2(micro-S)2(dmit)2] [(n-Bu4N)2[2]], which is formed via oxidation in air from the intermediate (n-Bu4N)2[Mo3(micro3-S)(micro-S)3(dmit)3] [(n-Bu4N)2[1]] complex. Ligand substitution of the molybdenum sulfur bridged [Mo2O2(micro-S)2(dimethylformamide)6]2+ dimer with the sodium salt of the dmit dithiolate also affords the dianionic compound (n-Bu4N)2[2]. The whole series, (n-Bu4N)2[Mo2O2(micro-Se)2(dmit)2] [(n-Bu4N)2[3]], (n-Bu4N)2[W2O2(micro-S)2(dmit)2] [(n-Bu4N)2[4]], (n-Bu4N)2[W2O2(micro-Se)2(dmit)2] [(n-Bu4N)2[5]], and (n-Bu4N)2[Mo2O2(micro-S)2(dmid)2] [(n-Bu4N)2[6]; dmid = 1,3-dithiole-2-one-4,5-dithiolate], has been synthesized by the excision of the polymeric (Mo3Q7Br4)x phases with PPh3 or 1,2-bis(diphenylphosphanyl)ethane in acetonitrile followed by the dithiolene incorporation and further degradation in air. Direct evidence of the presence of the intermediates with the formula [M3Q4(dmit)3]2- (M = Mo, W; Q = S, Se) has been obtained by electrospray ionization mass spectrometry. The crystal structures of (n-Bu4N)2[1], (PPh4)2[Mo2O2(micro-S)2(dmit)2] [(PPh4)2[2]; PPh4 = tetraphenylphosphonium], (n-Bu4N)2[2], (n-Bu4N)2[4], (PPh4)2[W2O2(micro-Se)2(dmit)2] [(PPh4)2[5]], and (n-Bu4N)2[6] have been determined. A detailed study of the gas-phase behavior for compounds (n-Bu4N)2[2-6] shows an identical fragmentation pathway for the whole family that consists of a partial breaking of the two dithiolene ligands followed by the dissociation of the dinuclear cluster.
authors.affiliation: Departament de Ciències Experimentals, Universitat Jaume I, Campus de Riu Sec, P.O. Box 224, 12080 Castelló, Spain. llusar@exp.uji.es
authors.forename: Rosa
authors.initials: R
authors.lastname: Llusar
authors.forename: Sonia
authors.initials: S
authors.lastname: Triguero
authors.forename: Cristian
authors.initials: C
authors.lastname: Vicent
authors.forename: Maxim N
authors.initials: MN
authors.lastname: Sokolov
authors.forename: Benoît
authors.initials: B
authors.lastname: Domercq
authors.forename: Marc
authors.initials: M
authors.lastname: Fourmigué
mesh_terms: D018011:Chalcogens / Q000737:chemistry; D015392:Chemistry, Inorganic / Q000379:methods; D002627:Chemistry, Physical / Q000379:methods; D018360:Crystallography, X-Ray; D005740:Gases; D015394:Molecular Structure; D008982:Molybdenum / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D014050:Toluene / Q000031:analogs & derivatives / Q000737:chemistry; D014414:Tungsten / Q000737:chemistry*
chemical_list: D018011:Chalcogens; D005740:Gases; D014050:Toluene; D008982:Molybdenum; C004848:dithiol; D014414:Tungsten