BREAKING NEWS
Cloud Server Hosting For Online Businesses
Inexpensive SEO Services
Benefits of Wanting to play Free Online Slot machines
Cyclooctadiene rhodium chloride dimer

Summary

Cyclooctadiene rhodium chloride dimer is the organorhodium compound with the formula Rh2Cl2(C8H12)2, commonly abbreviated [RhCl(COD)]2 or Rh2Cl2(COD)2. This yellow-orange, air-stable compound is a widely used precursor to homogeneous catalysts.[1]

Cyclooctadiene rhodium chloride dimer
Names
IUPAC name
di-μ-chlorido-bis[η2,η2-(cycloocta-1,5-diene)rhodium]
Other names
Cyclooctadiene rhodium chloride dimer
Identifiers
  • 12092-47-6 checkY
3D model (JSmol)
  • Interactive image
ChemSpider
  • 21171524 checkY
ECHA InfoCard 100.031.949 Edit this at Wikidata
EC Number
  • 235-157-6
  • 6436379
  • DTXSID20923606 Edit this at Wikidata
  • InChI=1S/2C8H12.2ClH.2Rh/c2*1-2-4-6-8-7-5-3-1;;;;/h2*1-2,7-8H,3-6H2;2*1H;;/q;;;;2*+1/p-2/b2*2-1-,8-7-;;;; checkY
    Key: QSUDXYGZLAJAQU-MIXQCLKLSA-L checkY
  • InChI=1/2C8H12.2ClH.2Rh/c2*1-2-4-6-8-7-5-3-1;;;;/h2*1-2,7-8H,3-6H2;2*1H;;/q;;;;2*+1/p-2/b2*2-1-,8-7-;;;;/r2C8H12.2ClRh/c2*1-2-4-6-8-7-5-3-1;2*1-2/h2*1-2,7-8H,3-6H2;;/b2*2-1-,8-7-;;
    Key: QSUDXYGZLAJAQU-PXXGERDABU
  • Cl1[Rh]Cl[Rh]1.C=1CC\C=C/CCC=1.C/1C\C=C/CC\C=C\1
Properties
C16H24Cl2Rh2
Molar mass 493.0806 g/mol
Density 1.93 g/cm3
Melting point 243 °C (469 °F; 516 K)
Solubility dichloromethane
Hazards
GHS labelling:
GHS07: Exclamation markGHS09: Environmental hazard
Warning
H302, H315, H317, H319, H335, H411
P261, P264, P270, P271, P272, P273, P280, P301+P312, P302+P352, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P333+P313, P337+P313, P362, P363, P391, P403+P233, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)
Infobox references

Preparation and reactions edit

The synthesis of [RhCl(COD)]2 involves heating a solution of hydrated rhodium trichloride with 1,5-cyclooctadiene in aqueous ethanol in the presence of sodium carbonate:[1][2]

2 RhCl3·3H2O + 2 COD + 2 CH3CH2OH + 2 Na2CO3 → [RhCl(COD)]2 + 2 CH3CHO + 8 H2O + 2 CO2 + 4 NaCl

[RhCl(COD)]2 is principally used as a source of the electrophile "[Rh(COD)]+."

[RhCl(COD)]2 + nL → [LnRh(COD)]+Cl− (where L = PR3, alkene, etc. and n = 2 or 3)

In this way, chiral phosphines can be attached to Rh. The resulting chiral complexes are capable of asymmetric hydrogenation.[3] A related but still more reactive complex is chlorobis(cyclooctene)rhodium dimer. The dimer reacts with a variety of Lewis bases (L) to form adducts with the stoichiometry RhCl(L)(COD).

Structure edit

The molecule consists of a pair of square planar Rh centers bound to a 1,5-cyclooctadiene and two chloride ligands that are shared between the Rh centers. The Rh2Cl2 core is also approximately planar,[4] in contrast to the highly bent structure of cyclooctadiene iridium chloride dimer where the dihedral angle is 86°.

References edit

  1. ^ a b Giordano, G.; Crabtree, R. H. "Di-μ-chloro-bis(η4-1,5-cyclooctadiene)dirhodium(I)" Inorganic Syntheses, 1990, volume 28, pages 88-90. doi:10.1002/9780470132593.ch22
  2. ^ Chatt, J.; Venanzi, L. M. (1956). "Olefin Complexes of Rhodium". Nature. 177 (4514): 852–3. Bibcode:1956Natur.177..852C. doi:10.1038/177852b0. S2CID 4296682.
  3. ^ W. S. Knowles (2003). "Asymmetric Hydrogenations (Nobel Lecture 2001)". Advanced Synthesis & Catalysis. 345 (1–2): 3–13. doi:10.1002/adsc.200390028.
  4. ^ "Di-μ-chloro-bis[(cis,cis-η4-1,5-cyclooctadiene)rhodium(I)]: a redetermination" De Ridder, Kirk J. A. Acta Crystallographica, Section C: Crystal Structure Communications 1994, C50, 1569-72. doi:10.1107/S0108270194001459

External links edit

  •   Media related to Cyclooctadiene rhodium chloride dimer at Wikimedia Commons

By using this platform, you agree to the Terms of Use ©2020 Knowpia