Dichlorotris(triphenylphosphine)ruthenium(II)

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.

Dichlorotris(triphenylphosphine)­ruthenium(II)
Dichlorotris(triphenylphosphine)ruthenium(II)
Names
IUPAC name
Dichlorotris(triphenylphosphine)ruthenium(II)
Other names
Ruthenium tris(triphenylphosphine) dichloride; Tris(triphenylphosphine)dichlororuthenium; Tris(triphenylphosphine)ruthenium dichloride;Tris(triphenylphosphine)ruthenium(II) dichloride
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.035.957 Edit this at Wikidata
EC Number
  • 239-569-7
  • InChI=1S/3C18H15P.2ClH.Ru/c3*1-4-10-16(11-5-1)19(17-12-6-2-7-13-17)18-14-8-3-9-15-18;;;/h3*1-15H;2*1H;/q;;;;;+2/p-2 checkY
    Key: WIWBLJMBLGWSIN-UHFFFAOYSA-L checkY
  • InChI=1/3C18H15P.2ClH.Ru/c3*1-4-10-16(11-5-1)19(17-12-6-2-7-13-17)18-14-8-3-9-15-18;;;/h3*1-15H;2*1H;/q;;;;;+2/p-2
    Key: WIWBLJMBLGWSIN-NUQVWONBAX
  • [Ru+2].[Cl-].[Cl-].c3c(P(c1ccccc1)c2ccccc2)cccc3.c1ccccc1P(c2ccccc2)c3ccccc3.c1ccccc1P(c2ccccc2)c3ccccc3
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°
Octahedral
Hazards
GHS labelling:
GHS07: Exclamation mark
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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Synthesis and basic properties

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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

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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

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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

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  1. ^ 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
  2. ^ 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
  3. ^ Sabo-Etienne, S.; Gellier, M., "Ruthenium: Inorganic and Coordination Chemistry", Encyclopedia of Inorganic Chemistry, 2006, John Wiley & Sons 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.
  4. ^ 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.
  5. ^ Georgios C. Vougioukalakis, Robert H. Grubbs "Ruthenium-Based Heterocyclic Carbene-Coordinated Olefin Metathesis Catalysts" Chem. Rev., 2010, volume 110, pp 1746–1787 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.
  6. ^ Schunn, R. A.; Wonchoba, E. R. (1972). "Chlorohydridotris(triphenylphosphine)ruthenium(II)". Inorganic Syntheses. Vol. 13. p. 131. doi:10.1002/9780470132449.ch26. ISBN 9780470132449.
  7. ^ Loges, B.; Boddien, A.; Junge, H.; Beller, M., "Controlled Generation of Hydrogen from Formic Acid Amine Adducs at Room Temperature and Application in H2/O2 Fuel Cells", Angew. Chem. Int. Ed., 2008, 47, 3962-3965 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.
  8. ^ 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
  9. ^ Shu-Yu, Z.; Yong-Qiang, T.; Chun-An, F.; Yi-Jun, J.; Lei, S.; Ke, C.; En, Z.; "Cross-Coupling Reactions between alcohols through sp3 C-H Activation Catalyzed by a Ruthenium/Lewis Acid System" Chem. Eur. J., 2008, 14, 10201-10205 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 sp3CH Activation Catalyzed by a Ruthenium/Lewis Acid System". Chemistry - A European Journal. 14 (33): 10201–10205. doi:10.1002/chem.200801317. PMID 18844197.