Hydride, alkyl and carbyne derivatives of the unsaturated heterometallic anion [MoWCp2(μ-PCy2)(μ-CO)2]-

被引:2
作者
Angeles Alvarez, M. [1 ]
Esther Garcia, M. [1 ]
Garcia-Vivo, Daniel [1 ]
Huergo, Estefania [1 ]
Ruiz, Miguel A. [1 ]
机构
[1] Univ Oviedo, Dept Quim Organ & Inorgan, IUQOEM, E-33071 Oviedo, Spain
关键词
Heterometallic complexes; Metal-metal interactions; Carbonylate complexes; Hydride complexes; Carbyne complexes; Agostic complexes; BRIDGED DIMOLYBDENUM COMPLEXES; TRANSITION-METAL HYDROGEN; SET MODEL CHEMISTRY; TOTAL ENERGIES; AB-INITIO; MO; CY; BONDS; CYCLOPENTADIENYL; ACTIVATION;
D O I
10.1016/j.jorganchem.2019.04.028
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
The heterometallic hydride [MoWCp2(mu-H)(mu-PCy2)(CO)(4)] was prepared in 30% yield through reaction of an equimolar mixture of [Mo2Cp2(CO)(6)] and [W2Cp2(CO)(6)] with a two-fold excess of PHCy2 in xylene solution, in a sealed tube at 453 K. The sodium salt of the title anion was then prepared from the latter hydride in a three-step process first involving dehydrogenation with HBF4 center dot OEt2 in dichloromethane to give the cationic derivative [MoWCp2(mu-PCy2)(CO)(4)](BF4), then reaction of the latter with NaI in refluxing 1,2-dichloroethane to yield the iodide-bridged dicarbonyl complex [MoWCp2(mu-I)(mu-PCy2)(CO)(2)] and, finally, reaction of the latter with Na(Hg) in tetrahydrofuran solution. Reaction of this anion with (NH4) PF6 gave the hydride [MoWCp2(H)(m-PCy2)(CO)(2)], which in solution displays an equilibrium mixture of two isomers, one with terminal carbonyls and the hydride ligand bridging the metal atoms (B), another one with a semibridging carbonyl and the hydride ligand terminally bound to the W atom (T). The prevalence of isomer T was higher than the observed ones in the corresponding homometallic analogues, and there was a clear thermodynamic preference of the hydride ligand for the W site, estimated in some 20 kJ/mol according to density functional theory (DFT) calculations. The title anion reacted selectively with benzyl chloride at room temperature, to give the agostic benzyl-bridged derivative [MoWCp2(mu-kappa(1): eta(2)-CH2Ph)(mu-PCy2)(CO)(2)], which displays specific k1-coordination to the W atom (MoeW 1/4 2.580(1) A), while the analogous reaction with MeI gave a mixture of the related methyl-bridged complex [MoWCp2(mu-k(1): eta(2)-CH3)(mu-PCy2)(CO)(2)] and its methoxycarbyne-bridged isomer [MoWCp2(m-COMe)(mPCy(2))( m-CO)] in a ratio of ca. 5:1, with the latter corresponding to a chemical behaviour intermediate between those of its homonuclear analogues. Photolysis of the above alkyl complexes with visible-UV light at room temperature resulted in fast decarbonylation followed by dehydrogenation, to give the corresponding carbyne-bridged derivatives [MoWCp2(m-CR)(m-PCy2)(m-CO)] (R = H, Ph) in good yield. This suggests that the cooperative action of Mo and W atoms greatly reduces the thermal barrier of the CeH bond cleavage steps required for dehydrogenation of the alkyl ligands in these substrates. (c) 2019 Elsevier B. V. All rights reserved.
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页码:61 / 71
页数:11
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共 61 条
[1]   CHEMISTRY OF PHOSPHIDO-BRIDGED DIMOLYBDENUM COMPLEXES .3. REINVESTIGATION OF THE REACTION BETWEEN [MO2(ETA-C5H5)2(CO)6] AND P2PH4 - X-RAY STRUCTURES OF [MO2(MU-C5H5)2(MU-PPH2)2(CO)2], [MO2(ETA-C5H5)2(MU-PPH2)2(MU-CO)], AND TRANS-[MO2(ETA-C5H5)2(MU-PPH2)2O(CO)] [J].
ADATIA, T ;
MCPARTLIN, M ;
MAYS, MJ ;
MORRIS, MJ ;
RAITHBY, PR .
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 1989, (08) :1555-1564
[2]   Trapping of hemiquinone radicals at Mo and P sites by phosphide-bridged dimolybdenum species:: Chemistry of complexes [Mo2(η5-C5H5)2(OC6H4OH)(μ-PR2)(CO)4] and [Mo2(η5-C5H5)2{μ-PR(OC6H4OH)}(CO)4]-(R = Cy, Ph) [J].
Alvarez, Celedonio M. ;
Alvarez, M. Angeles ;
Alonso, Maria ;
Garcia, M. Esther ;
Rueda, M. Teresa ;
Ruiz, Miguel A. ;
Herson, Patrick .
INORGANIC CHEMISTRY, 2006, 45 (23) :9593-9606
[3]   Chemical and electrochemical oxidation of diphenylphosphide-bridged hydrides [M2 (η5-C5H5)2(μ-H)(μ-PPh2)(CO)4] and anions [M2(η5-C5H5)2(μ-PPh2)(CO)4]- (M = mo, w) [J].
Alvarez, CM ;
García, ME ;
Rueda, MT ;
Ruiz, MA ;
Sáez, D .
ORGANOMETALLICS, 2005, 24 (04) :650-658
[4]   A triply bonded dimolybdenum hydride complex with acid, base and radical activity [J].
Alvarez, CM ;
Alvarez, MA ;
García, ME ;
Ramos, A ;
Ruiz, MA ;
Lanfranchi, M ;
Tiripicchio, A .
ORGANOMETALLICS, 2005, 24 (01) :7-9
[5]   Proton induced P-H and Mo-H bond activation at the phosphide bridged dimolybdenum complexes [Mo2Cp2(μ-H)(μ-PHR)(CO)4] (R = Cy, 2,4,6-C6H2R′3; R′ = H, Me, tBu) [J].
Alvarez, CM ;
Alvarez, MA ;
García-Vivó, D ;
García, ME ;
Ruiz, MA ;
Sáez, D ;
Falvello, LR ;
Soler, T ;
Herson, P .
DALTON TRANSACTIONS, 2004, (24) :4168-4179
[6]   Reactivity of the α-agostic methyl bridge in the unsaturated complex [Mo2(η5-C5H5)2(μ-η1:η2-CH3)(μ-PCy2)(CO)2]:: Migratory behavior and methylidyne derivatives [J].
Alvarez, M. Angeles ;
Garcia-Vivo, Daniel ;
Garcia, M. Esther ;
Martinez, M. Eugenia ;
Ramos, Alberto ;
Ruiz, Miguel A. .
ORGANOMETALLICS, 2008, 27 (09) :1973-1975
[7]   Structural and Chemical Effects of the PtBu2 Bridge at Unsaturated Dimolybdenum Complexes Having Hydride and Hydrocarbyl Ligands [J].
Angeles Alvarez, M. ;
Casado-Ruano, Melodie ;
Esther Garcia, M. ;
Garcia-Vivo, Daniel ;
Ruiz, Miguel A. .
INORGANIC CHEMISTRY, 2017, 56 (18) :11336-11351
[8]   Reactions of the Unsaturated Ditungsten Anion [W2Cp2(μ-PCy2)(μ-CO)2]- with C- and P-Based Electrophiles [J].
Angeles Alvarez, M. ;
Esther Garcia, M. ;
Garcia-Vivo, Daniel ;
Ruiz, Miguel A. ;
Fernanda Vega, M. .
ORGANOMETALLICS, 2015, 34 (05) :870-878
[9]   Hydride, gold(I) and related derivatives of the unsaturated ditungsten anion [W2Cp2(μ-PCy2)-(μ-CO)2]- [J].
Angeles Alvarez, M. ;
Esther Garcia, M. ;
Garcia-Vivo, Daniel ;
Ruiz, Miguel A. ;
Fernanda Vega, M. .
DALTON TRANSACTIONS, 2014, 43 (42) :16044-16055
[10]   Binuclear Carbyne and Ketenyl Derivatives of the Alkyl-Bridged Complexes [Mo2(η5-C5H5)2(μ-CH2R)(μ-PCy2)(CO)2] (R = H, Ph) [J].
Angeles Alvarez, M. ;
Esther Garcia, M. ;
Garcia-Vivo, Daniel ;
Eugenia Martinez, M. ;
Ruiz, Miguel A. .
ORGANOMETALLICS, 2011, 30 (08) :2189-2199