16800-47-8Relevant academic research and scientific papers
Relative hemilabilities of H2B(az)2 (az = pyrazolyl, dimethylpyrazolyl, methimazolyl) chelates in the complexes [M(η-C3H5)(CO)2{H2B(az)2}] (M = Mo, W)
Abernethy, Robyn J.,Foreman, Mark R. St.-J.,Hill, Anthony F.,Smith, Matthew K.,Willis, Anthony C.
, p. 781 - 796 (2020)
The reactions of [M(η3-C3H5)Br(CO)2(NCMe)2] (M = Mo, W) or [Mo(η3-C3H5)Br(CO)2(PMe2Ph)2] with Na[H2B(mt)2] (mt = methimazolyl) affords the complexes [M(η3-C3H5)(CO)2{κ3-H,S,S′-H2B(mt)2}], the 3-centre, 2-electron B-H-M interaction of which was found to be inert with respect to opening under mild conditions, while more forcing conditions (heating with PMe2Ph) resulted in cleavage of the entire allyl and borate ligands to form [Mo(CO)3(PMe2Ph)3]. In contrast, the reaction of [Mo(η3-C3H5)Br(CO)2(NCMe)2] with Na[H2B(pz)2] affords either [Mo(η3-C3H5)(CO)2{κ3-H,N,N′-H2B(pz)2}] or (more likely) [Mo(η3-C3H5)(CO)2(NCMe){κ2-N,N′-H2B(pz)2}] which in turn reacts with phosphines to provide [[Mo(η3-C3H5)(CO)2(PPhR2){κ2-N,N′-H2B(pz)2}] (R = Me, Ph). The reactions discussed indicate the propensity for 3-centre, 2-electron B-H-Mo interactions increases in the order H2B(pz)2 2B(pz?)2 2B(mt)2 (pz? = 3,5-dimethypyrazolyl).
Photochemistry of bis[cyclopentadienyltricarbonyltungsten] with diphenyl diselenide to produce (benzeneselenato)cyclopentadienyltricarbonyltungsten
Abrahamson, Harmon B.,Marxen, Heather
, p. 2835 - 2840 (1993)
Visible- light photolysis of [CpW(CO)3]2 with diphenyl diselenide in THF or toluene produces good yields of CpW(CO)3SePh. Nonempirical Fenske-Hall MO calculations are used to compare the bonding in the CpW(CO)3S
Aryl Oligogermanes as Ligands for Transition Metal Complexes
Zaitsev, Kirill V.,Lam, Kevin,Tafeenko, Viktor A.,Korlyukov, Alexander A.,Poleshchuk, Oleg Kh.
, p. 4911 - 4924 (2018/12/11)
The ligand properties of a series of aryl oligogermanes R3Ge-GeAr3, 3–7 [Me3Ge-GePh3 (3), Me3Ge-Ge(pTol)3 (4), Ph3Ge-GePh3 (5), (C6F5)3Ge-GePh3 (6), Ph3Ge-GeMe2GePh3 (7)] for the synthesis of transition metal carbonyl complexes such as R3Ge-GeAr2(R′C6H4-η6)M(CO)3 (M = Cr, 3a–7a; M = Mo, 3b; M = W, 3c) were investigated. The target complexes were obtained in moderate yields using several different synthetic approaches. The physicochemical properties of these new derivatives were investigated by IR, UV/Vis, NMR spectroscopy, electrochemistry, and DFT calculations. The molecular structures of 3c, 4a, and 5a were studied by single-crystal X-ray diffraction analysis. A comparative analysis of donor and acceptor properties of aryl oligogermanes as ligands for transition metal carbonyl complexes is reported.
On the coordination chemistry of corannulene, the smallest "buckybowl"
Stoddart, Michael W.,Brownie, John H.,Baird, Michael C.,Schmider, Hartmut L.
, p. 3440 - 3450 (2007/10/03)
A variety of methods, conventional and non-conventional, are used in attempts to prepare the compounds (η6-corannulene)M(CO) 3 (M = Cr, Mo, W), all unsuccessful. Conventional methods are also utilized in attempts to prepare the compound [CpFe(η6- corannulene)]PF6, but these result in mixtures of cationic CpFe(arene) complexes containing partially hydrogenated corannulene; similar results have been reported for other polyaromatic hydrocarbons. DFT calculations on the compound (η6-corannulene)Cr(CO)3 suggest that the (η6-corannulene)-Cr linkage is only a few kcal/mol weaker than the corresponding bond in (η6-benzene)Cr(CO)3, implying that failures in syntheses arise from kinetic, not thermodynamic problems.
Synthesis and structures of dinuclear iron, molybdenum and tungsten complexes derived from (PhCHCHPh)-coupled bis(cyclopentadiene)
Li, Bin,Wang, Baiquan,Xu, Shansheng,Zhou, Xiuzhong
, p. 5309 - 5317 (2007/10/03)
Reductive coupling of phenylfulvene with amalgamated calcium metal followed by hydrolysis yields CpPhCHCHPhCp (1) in high yield. Refluxing ligand 1 and Fe(CO)5 in xylene produces (PhCHCHPh)-coupled bis(cyclopentadienyl) tetracarbonyl diiron (PhCHCHPh)[(η5-C5H 4)Fe(CO)2]2 (2) as a mixture of meso (2-meso) and racemic isomers (2-rac). The pure racemic isomers of the Mo and W analogues (3-rac and 4-rac) have been synthesized by lithiation of ligand 1 and addition of (MeCN)3M(CO)3 (M = Mo, W) followed by oxidation with 2 equiv. of ferrocenium tetrafluoroborate. All the new complexes have been fully characterized. The molecular structures of 1-meso, 2-meso, 2-rac, 3-rac, and 4-rac have been determined by X-ray diffraction analysis.
Synthesis and characterization of 6,7 and 8-coordinate monomeric complexes of tungsten obtained from reaction of [W(CO)3(MeCN)3] with pyridine-2-thiol (pySH) and PPh3
Anjumanara,Begum, Noorjahan,Camellia, Farzana K.,Kabir, Shariff E.,Kundu, Kalipada
, p. 1123 - 1125 (2007/10/03)
Complexes [W(CO)4(PPh3)2] 1, [W(CO) 4(pySH)(PPh3)] 2, [W(CO)2(pyS) 2(PPh3)] 3 and [W(pyS)4] 4 have been obtained from the reaction of [W(CO)3(MeCN)3] with pyridine-2-thiol (pySH) and PPh3 in refluxing THF. 1 and 2 are normal 6-coordinate complexes but 3 and 4 are unusual 7 and 8-coordinate complexes, respectively. The complexes have been characterized by IR, 1H and 31P{1H}NMR, mass spectra and elemental analysis.
Syntheses, characterization and structures of chromium group carbonyl complexes containing a multifunctional Ph2P(o-C6H4)CH=N(CH2) 2(o-C6H4N) ligand
Yang, Ching-Chao,Yeh, Wen-Yann,Lee, Gene-Hsiang,Peng, Shie-Ming
, p. 353 - 358 (2007/10/03)
Reactions of the phosphine-imine-pyridine-containing ligand Ph2P(o-C6H4)CH=N(CH2) 2(o-C6H4N) (PNN) with M(CO)3(NCMe)3 (M=Cr, Mo, W) produce the tridentate complexes fac-M(CO)3(η3-PNN). On the other hand, treating W(CO)4(NCMe)2 with PNN results in the bidentate complex W(CO)4(η2-PNN), which converts to fac-W(CO)3(η3-PNN) upon heating, but no facial→meridional isomerism is evidenced. The new compounds have been characterized by elemental analysis and mass, IR, and NMR spectroscopy. The molecular structures of W(CO)4(η2-PNN), fac-W(CO)3(η3-PNN) and fac-Mo(CO)3(η3-PNN) are determined by an X-ray diffraction study.
Tris[(alkylthio)methyl]silanes: Syntheses and structures of chromium, molybdenum, and tungsten complexes with a tripodal thioether ligand
Yim, Hing W.,Tran, Linh M.,Dobbin, Ebern D.,Rabinovich, Daniel,Liable-Sands, Louise M.,Incarvito, Christopher D.,Lam, Kin-Chung,Rheingold, Arnold L.
, p. 2211 - 2215 (2008/10/08)
The first member of a new family of tripodal thioether ligands, the methyltris[(alkylthio)methyl]silanes MeSi-(CH2SR)3 (R = Me), has been synthesized and characterized. Reactivity studies lead to the isolation of the complete series of group 6 metal carbonyl derivatives {η3-MeSi(CH2SMe)3}M(CO)3 (M = Cr, Mo, W), whose structures have been determined by single-crystal X-ray diffraction. The three complexes are isomorphous and display distorted octahedral structures with face-capping tridentate thioether ligands. {η3-MeSi(CH2SMe)3}Cr(CO)3 is monoclinic, P21/c, a = 8.1658(2) A?, b = 15.0563(2) A?, c = 26.5791(3) A?, β= 90.3653(6)°, V = 3267.74(8) A?3, Z = 8. {η3-MeSi(CH2SMe)3}Mo(CO)3 is monoclinic, P21/c, a = 8.34630(6) A, b = 15.2747(2) A?, c = 27.1865(4) A?, β = 90.8987(9)°, V= 3465.44(10) A?3, Z = 8. {η3-MeSi(CH2SMe)3}W(CO)3 is monoclinic, P21/c, a = 8.1582(2) A?, b = 14.9903(2) A?, c = 26.7268(4) A?, β = 90.6568(8)°, V = 3268.30(9) A?3, Z = 8.
Comparison of a range of rhodium-based catalysts for the hydroformylation of selected alkenes
Dickson,Gladiali,Bowen,Campi,Jackson,Jonasson,McGrath,Paslow,Polas,Renton
, p. 133 - 146 (2008/10/09)
To determine whether the activity and selectivity of bimetallic catalysts improve during the hydroformylation of alkenes compared to their monometallic counterparts, the hydroformylation of styrene, 1-hexene, and a variety of amino- and phosphino-alkenes using four Rh-based catalyst systems ((OC)4W(μ-PPh2)2RhH(CO)(PPh3), (OC)2RhMo(CO)3(C5H4PPh2), (OC)2RhW(CO)3(C5H4PPh2), and [Rh(OAc)2]2/PPh3) was investigated. The Rh-catalyzed reactions of unsaturated amines with H2/CO differed in chemo- and regioselectivity depending on the catalyst and the reaction conditions. The reactions of unsaturated amides differed in product ratios with varying catalyst systems.
1,3,5-Trimethyl-1,3,5-triazacyclohexane tricarbonyl complexes of Mo and W as sources of the fac-M(CO)3 fragment. Mild syntheses of fac-[M(CO)3(CH3CN)3] (M=Mo, W), [W(CO)3(PR3)3], [W(CO)(alkyne)3] and [W(CO)3(π-arene)] complexes
Baker, Murray V.,North, Michael R.
, p. 225 - 230 (2007/10/03)
The 1,3,5-trimethyl-1,3,5-triazacyclohexane (Me3tach) group in [M(CO)3(Me3tach)] complexes (M=Mo, W) is easily displaced by a variety of ligands under mild conditions. The lability of the Me3tach ligand allows the [M(CO)3(Me3tach)] complexes to be used as synthetic intermediates in convenient syntheses of products such as fac-[M(CO)3(CH3CN)3] (M=Mo, W), [W(CO)(alkyne)3], [W(CO)3(PR3)3] and [W(CO)3(η6-arene)] complexes. An improved synthesis of [W(CO)3(Me3tach)] from [W(CO)6] and Me3tach is described.
