Dichlorotris(triphenylphosphine)ruthenium(II)
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| Names | |
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| IUPAC name
Dichlorotris(triphenylphosphine)ruthenium(II)
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| Other names
Ruthenium tris(triphenylphosphine) dichloride; Tris(triphenylphosphine)dichlororuthenium; Tris(triphenylphosphine)ruthenium dichloride;Tris(triphenylphosphine)ruthenium(II) dichloride
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| Identifiers | |
3D model (JSmol)
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| ChemSpider | |
| ECHA InfoCard | 100.035.957 |
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PubChem CID
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CompTox Dashboard (EPA)
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| Properties | |
| C54H45Cl2P3Ru | |
| Molar mass | 958.83 g/mol |
| Appearance | Black Crystals or Red-Brown |
| Density | 1.43 g cm−3 |
| Melting point | 133 °C; 271 °F; 406 K |
| Structure | |
| Monoclinic | |
| C2h5-P21/c | |
a = 18.01 Å, b = 20.22 Å, c = 12.36 Å α = 90°, β = 90.5°, γ = 90°
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| Octahedral | |
| Hazards | |
| GHS labelling: | |
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| Warning | |
| H302, H312, H332 | |
| P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P312, P304+P340, P312, P322, P330, P363, P501 | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Dichlorotris(triphenylphosphine)ruthenium(II) is a coordination complex of ruthenium. It is a chocolate brown solid that is soluble in organic solvents such as benzene. The compound is used as a precursor to other complexes including those used in homogeneous catalysis.
Synthesis and basic properties
[edit]RuCl2(PPh3)3 is the product of the reaction of ruthenium trichloride trihydrate with a methanolic solution of triphenylphosphine.[1][2]
- 2 RuCl3(H2O)3 + 7 PPh3 → 2 RuCl2(PPh3)3 + 2 HCl + 5 H2O + OPPh3
The coordination sphere of RuCl2(PPh3)3 can be viewed as either five-coordinate or octahedral. One coordination site is occupied by one of the hydrogen atoms of a phenyl group.[3] This Ru---H agostic interaction is long (2.59 Å) and weak. The low symmetry of the compound is reflected by the differing lengths of the Ru-P bonds: 2.374, 2.412, and 2.230 Å.[4] The Ru-Cl bond lengths are both 2.387 Å.
Reactions
[edit]In the presence of excess of triphenylphosphine, RuCl2(PPh3)3 binds a fourth phosphine to give black RuCl2(PPh3)4. The triphenylphosphine ligands in both the tris(phosphine) and tetrakis(phosphine) complexes are readily substituted by other ligands. The tetrakis(phosphine) complex is a precursor to the Grubbs catalysts.[5]
Dichlorotris(triphenylphosphine)ruthenium(II) reacts with hydrogen in the presence of base to give the purple-colored monohydride HRuCl(PPh3)3.[6]
- RuCl2(PPh3)3 + H2 + NEt3 → HRuCl(PPh3)3 + [HNEt3]Cl
Dichlorotris(triphenylphosphine)ruthenium(II) reacts with carbon monoxide to produce the all trans isomer of dichloro(dicarbonyl)bis(triphenylphosphine)ruthenium(II).
- RuCl2(PPh3)3 + 2 CO → trans,trans,trans-RuCl2(CO)2(PPh3)2 + PPh3
This kinetic product isomerizes to the cis adduct during recrystallization. trans-RuCl2(dppe)2 forms upon treating RuCl2(PPh3)3 with dppe.
- RuCl2(PPh3)3 + 2 dppe → RuCl2(dppe)2 + 3 PPh3
RuCl2(PPh3)3 catalyzes the decomposition of formic acid into carbon dioxide and hydrogen gas in the presence of an amine.[7] Since carbon dioxide can be trapped and hydrogenated on an industrial scale, formic acid represents a potential storage and transportation medium.
Use in organic synthesis
[edit]RuCl2(PPh3)3 facilitates oxidations, reductions, cross-couplings, cyclizations, and isomerization. It is used in the Kharasch addition of chlorocarbons to alkenes.[8]
Dichlorotris(triphenylphosphine)ruthenium(II) serves as a precatalyst for the hydrogenation of alkenes, nitro compounds, ketones, carboxylic acids, and imines. On the other hand, it catalyzes the oxidation of alkanes to tertiary alcohols, amides to t-butyldioxyamides, and tertiary amines to α-(t-butyldioxyamides) using tert-butyl hydroperoxide. Using other peroxides, oxygen, and acetone, the catalyst can oxidize alcohols to aldehydes or ketones. Using dichlorotris(triphenylphosphine)ruthenium(II) the N-alkylation of amines with alcohols is also possible (see "borrowing hydrogen").[8]
RuCl2(PPh3)3 efficiently catalyzes carbon-carbon bond formation from cross couplings of alcohols through C-H activation of sp3 carbon atoms in the presence of a Lewis acid.[9]
References
[edit]- ^ Stephenson, T. A.; Wilkinson, G. "New Complexes of Ruthenium (II) and (III) with Triphenylphosphine, Triphenylarsine, Trichlorostannate, Pyridine, and other Ligands", J. Inorg. Nucl. Chem., 1966, 28, 945-956. doi:10.1016/0022-1902(66)80191-4
- ^ P. S. Hallman, T. A. Stephenson, G. Wilkinson "Tetrakis(Triphenylphosphine)Dichloro-Ruthenium(II) and Tris(Triphenylphosphine)-Dichlororuthenium(II)" Inorganic Syntheses, 1970 volume 12 doi:10.1002/9780470132432.ch40
- ^ Sabo-Etienne, Sylviane; Grellier, Mary (2006). "Ruthenium: Inorganic & Coordination Chemistry Based in part on the article Ruthenium: Inorganic & Coordination Chemistry by Bruno Chaudret & Sylviane Sabo-Etienne which appeared in the Encyclopedia of Inorganic Chemistry, First Edition". Encyclopedia of Inorganic Chemistry. doi:10.1002/0470862106.ia208. ISBN 0470860782.
- ^ La Placa, Sam J.; Ibers, James A. (1965). "A Five-Coordinated d6 Complex: Structure of Dichlorotris(triphenylphosphine)ruthenium (II)". Inorganic Chemistry. 4 (6): 778–783. doi:10.1021/ic50028a002.
- ^ Vougioukalakis, Georgios C.; Grubbs, Robert H. (2010). "Ruthenium-Based Heterocyclic Carbene-Coordinated Olefin Metathesis Catalysts". Chemical Reviews. 110 (3): 1746–1787. doi:10.1021/cr9002424. PMID 20000700.
- ^ Schunn, R. A.; Wonchoba, E. R. (1972). "Chlorohydridotris(triphenylphosphine)ruthenium(II)". Inorganic Syntheses. Vol. 13. p. 131. doi:10.1002/9780470132449.ch26. ISBN 9780470132449.
- ^ Loges, Björn; Boddien, Albert; Junge, Henrik; Beller, Matthias (2008). "Controlled Generation of Hydrogen from Formic Acid Amine Adducts at Room Temperature and Application in H2/O2Fuel Cells". Angewandte Chemie International Edition. 47 (21): 3962–3965. doi:10.1002/anie.200705972. PMID 18457345.
- ^ a b Plummer, J. S.; Shun-Ichi, M.; Changjia, Z. "Dichlorotris(triphenylphosphine)ruthenium(II)", e-EROS Encyclopedia of Reagents for Organic Synthesis, 2010, John Wiley doi:10.1002/047084289X.rd137.pub2
- ^ Zhang, Shu-Yu; Tu, Yong-Qiang; Fan, Chun-An; Jiang, Yi-Jun; Shi, Lei; Cao, Ke; Zhang, En (2008). "Cross-Coupling Reaction between Alcohols through sp3 C−H Activation Catalyzed by a Ruthenium/Lewis Acid System". Chemistry - A European Journal. 14 (33): 10201–10205. doi:10.1002/chem.200801317. PMID 18844197.