Grubbs Catalyst® M204


Grubbs Catalyst® M2a (C848), Benzylidene[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(tricyclohexylphosphine)ruthenium, (1,3-Bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)dichloro(phenylmethylene)(tricyclohexylphosphine)ruthenium, Grubbs Catalyst® 2nd Generation, Dichloro[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene](benzylidene)(tricyclohexylphosphine)ruthenium(II)
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
PubChem Substance ID:

Quality Level

reaction suitability

core: ruthenium
reagent type: catalyst
reaction type: Ring-Opening Polymerization


143.5-148.5 °C

storage temp.



Grubbs Catalyst® M204 can be used as a catalyst for ring-closing metathesis (RCM), cross-metathesis, and ring-opening metathesis polymerization (ROMP). It is also used to synthesize trisubstituted olefins with excellent functional group tolerance and selectivity via cross-metathesis and ring closing metathesis reactions.
It can also be used as a catalyst:
  • To synthesize coumarins from phenolic compounds via RCM.
  • To cleave secondary (E)-allyl vic-diols to aldehydes.


2, 10 g in glass bottle
100, 500 mg in glass bottle

Legal Information

Product of Umicore

Product License
This product, its manufacturing or use, is the subject of one or more issued or pending U.S. Patents (and foreign equivalents) owned or controlled by Umicore PMC. The purchase of this product from Umicore PMC through Sigma-Aldrich, its affiliates or their authorized distributors conveys to the buyer a limited, one-time, non-exclusive, non-transferable, non-assignable license. Buyer′s use of this product may infringe patents owned or controlled by third parties. It is the sole responsibility of buyer to ensure that its use of the product does not infringe the patent rights of third parties or exceed the scope of the license granted herein.

For any further information on product please refer to your local Umicore PMC contact at http://www.pmc.umicore.com,
Grubbs Catalyst is a registered trademark of Umicore



Signal Word


Hazard Statements

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves


UN1325 - class 4.1 - PG 2 - Flammable solids, organic, n.o.s., HI: all

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

Certificate of Origin

  1. Which document(s) contains shelf-life or expiration date information for a given product?

    If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.

  2. What is the difference between the First and Second Generation Grubbs Catalyst?

    The Second Generation Catalyst has the same uses in organic synthesis as the First Generation Catalyst, but it has a higher activity.

A modified three-field technique for breast treatment.
Svensson GK, et al.
International Journal of Radiation Oncology, Biology, Physics, 6(6), 689-694 (1980)
D L Wright et al.
Organic letters, 3(26), 4275-4277 (2002-01-11)
The ring-opening cross-metathesis of oxabicyclo[3.2.1]octene derivatives provides a convenient method for preparing differentially substituted 4-pyrones. The major competing reaction is the ring-opening metathesis polymerization of the bridged olefin. Studies on this reaction have shown that substituents on the bicyclic alkene...
Shawn J Stachel et al.
Journal of medicinal chemistry, 49(21), 6147-6150 (2006-10-13)
A macrocyclic inhibitor of beta-secretase was designed by covalently cross-linking the P1 and P3 side chains of an isophthalamide-based inhibitor. Macrocyclization resulted in significantly improved potency and physical properties when compared to the initial lead structures. More importantly, these macrocyclic...
Highly selective cross-metathesis with phenyl vinyl sulphone using the `second generation?Grubbs? catalyst
Grela K and Bieniek M
Tetrahedron Letters, 42(36), 6425-6428 (2001)
M Scholl et al.
Organic letters, 1(6), 953-956 (2000-05-24)
[formula: see text] A new family of 1,3-dimesityl-4,5-dihydroimidazol-2-ylidene-substituted ruthenium-based complexes 9a-c has been prepared starting from RuCl2(=CHPh)(PCy3)2 2. These air- and water-tolerant complexes were shown to exhibit an increased ring-closing metathesis activity at elevated temperature when compared to that of...
TPGS-750-M, a second generation surfactant, is useful for room temperature, palladium and ruthenium-catalyzed reactions in water. Reactions include the Heck reaction, Suzuki-Miyaura reaction, Sonogashira reaction, Buchwald-Hartwig amination reaction, Negishi reaction, and olefin metathesis.
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