(Cymene)ruthenium dichloride dimer

(cymene)ruthenium dichloride dimer
Other names Dichloro(p-cymene)ruthenium(II) dimer
Identifiers
CAS number	52462-29-0 Y
ChemSpider	8297222 Y
Jmol-3D images	Image 1 Image 2
SMILES [Ru+2].[Ru+2].[Cl-].[Cl-].[Cl-].[Cl-].c1cc(ccc1C(C)C)C.c1cc(ccc1C(C)C)C Cc1ccc(cc1)C(C)C.Cc1ccc(cc1)C(C)C.[Cl-].[Cl-].[Cl-].[Cl-].[Ru+2].[Ru+2]
InChI InChI=1S/2C10H14.4ClH.2Ru/c2*1-8(2)10-6-4-9(3)5-7-10;;;;;;/h2*4-8H,1-3H3;4*1H;;/q;;;;;;2*+2/p-4 Y Key: LAXRNWSASWOFOT-UHFFFAOYSA-J Y InChI=1/2C10H14.4ClH.2Ru/c2*1-8(2)10-6-4-9(3)5-7-10;;;;;;/h2*4-8H,1-3H3;4*1H;;/q;;;;;;2*+2/p-4 Key: LAXRNWSASWOFOT-XBHQNQODAM
Properties
Molecular formula	C20H28Cl4Ru2
Molar mass	612.39 g mol−1
Appearance	Red solid
Melting point	247-250 °C (decomp.)
Solubility in water	Slightly, with hydrolysis
Y dichloride dimer (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

(Cymene)ruthenium dichloride dimer is the organometallic compound with the formula [(cymene)RuCl₂]₂. This red-coloured, diamagnetic solid is a reagent in organometallic chemistry and homogeneous catalysis.

Preparation and reactions

The dimer is prepared by the reaction of the phellandrene with hydrated ruthenium trichloride.^[1] Upon heating, [(cymene)RuCl₂]₂ undergoes exchange with other arenes, releasing free p-cymene. This dimeric molecule cleaves easily in the presence of Lewis bases to give monomeric adducts:

[(cymene)RuCl₂]₂ + 2 PPh₃ → 2 (cymene)RuCl₂(PPh₃)

Such monomers adopt pseudo-octahedral piano-stool structures.

Treatment of [(cymene)RuCl₂]₂ with the chelating anionic ligand precursor TsDPENH gives (cymene)Ru(TsDPEN-H), a catalyst for asymmetric transfer hydrogenation.^[2]

New catalysts

[(cymene)RuCl₂]₂ is also used to prepare catalysts (by monomerization with dppf) used in borrowing hydrogen catalysis^[3], a catalytic reaction that is based on the activation of alcohols towards nucleophilic attack.

References

1. ^ Bennett, M. A.; Huang, T. N.; Matheson, T. W. , Smith, A. K. "(η⁶-Hexamethylbenzene)ruthenium Complexes", Inorganic Syntheses, 1982, volume 21, pages 74–8.
2. ^ Takao Ikariya, Shohei Hashiguchi, Kunihiko Murata, and Ryōji Noyori (2005), "Preparation of Optically Active (R,R)-Hydrobenzoin from Benzoin or Benzil", Org. Synth.: 10, http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=v82p0010 
3. ^ Hamid et al.; Advanced Synthesis & Catalysis Volume 349, Issue 10, pages 1555–1575, July 2, 2007; doi:10.1002/adsc.200600638