Ruthenium catalysts for metathesis

Diver has recently reported new entries for the assembly of tetracyclic compounds.304 Interestingly, ruthenium catalysts for metathesis have also yielded tricyclic products by incorporating a cyclopropane from dienynes, a process reminiscent of Dixneuf s work (see above). 

Grela, K., Harutyunyan, S., Michrowska, A., A highly efficient ruthenium catalyst for metathesis reactions, Angew. Chem. Int. Edit. 2002, 41 4038-4040. 

For a thorough review of Ru-NHC-catalysts for metathesis, see Samojlowicz C, Bieniek M, Grela K (2009) Chem Rev 109 3708-3742 for ruthenium indenylidene-complexes in cross metathesis, see Boeda F, Bantreil X, Clavier H, Nolan SP (2008) Adv Synth Catal 350 2959-2966 For Hll-types systems, see Schrodi Y, Pederson RL (2007) Aldrichimica Acta 40 45-52... 

WO 2009/124853 Al, F Hoffmann-La Roche AG New ruthenium complexes as catalysts for metathesis reactions... 

A Novel Class of Ruthenium Catalysts for Olefin Metathesis, T. Weskamp,... 

W. C. SCHATTENMANN, M. SpiEGLER, et at, Angew. Chem. 1998, 110, 2631-2633 Angew. Chem. Int. Ed. 1998, 37, 2490-2493 (b) Highly Active Ruthenium Catalysts for Olefin Metathesis The Synergy of N-Heterocyclic Carbenes and Coordi-natively Labile Ligands, T. Weskamp,... 

Asymmetric Olefin Metathesis Using Ruthenium Catalysts Ruthenium catalysts for asymmetric synthesis have also been developed (Figure 6.3). 

J. Wolf, W. Stuer, C. Grunwald, H. Werner, P. Schwab, and M. Schulz, Ruthenium Trichloride, Tricyclohexylphosphane, 1-Alkynes, Magnesium, Hydrogen, and Water-Ingredients of an Efficient One-Pot Synthesis of Ruthenium Catalysts for Olefin Metathesis, Angew. Chem. Int. Ed. 37, 1124-1126 (1998). 

J. M. Berlin, S. D. Goldberg, and R. H. Grubbs, Highly Active Chiral Ruthenium Catalysts for Asymmetric Cross- and Ring-Opening Cross-Metathesis, Angew. Chem. Int. Ed. 45, 7591-7595 (2006). 

J. C. Conrad, D. Amoroso, P. Czechura, G. P. A. Yap, andD. E. Fogg, The First Highly Active, Halide-Free Ruthenium Catalyst for Olefin Metathesis, Organometallics 22, 3634-3636 (2003). 

Figure 333 Achiral and chiral ruthenium catalysts for olefin metathesis reactions.

Grubbs catalyst (Section 26.6) A widely used ruthenium catalyst for olefin metathesis that has the structure Cl2(Cy3P)2Ru=CHPh. 

A series of easily prepared and exceptionally active ruthenium catalysts for ringopening metathesis polymerization (ROMP) have been reported. As mentioned previously, the reaction of isoprene with RuCh gave a bis(jt-allyl)ruthenium(IV) complex of [RuC1(m-C1)( -CioHi6)]2, which was converted into cationic bis(jt-allyl)-ruthenium(IV) complexes by treatment with silver tetrafluoroborate. All of these complexes are stable in air and in solution for several hours. Although alone they... 

Highly active ruthenium (pre)catalysts for metathesis reactions... 

HIGHLY ACTIVE RUTHENIUM (PRE)CATALYSTS FOR METATHESIS REACTIONS... 

Due in large part to the development of ruthenium catalysts, olefin metathesis reactions can now be carried out on a diverse array of functionalized electron-rich and electron-poor olefins. As we have described, mechanistic analysis was instrumental in the design of more highly active second generation catalysts with expanded substrate scope, which was achieved by proper differentiation of the two L-type ligands within the (L)2(X)2Ru=CHR framework. Further investigations have revealed that these new catalysts display several unexpected features, and mechanistic analysis continues to be an invaluable tool for understanding reactivity patterns and for the development of new catalyst systems. 

Fig. 4.38. Molybdenum and ruthenium catalysts for asymmetric olefin metathesis reactions.

The structures of three important ruthenium complexes used as catalysts for metathesis are given on p. 1025. 

Evaluation of ruthenium catalysts for ring-op>ening metathesis polymerization-based selfhealing applications. Chem Mater 2008 20(10) 3288-97 [suprporting information]. 

Grubbs and co-workers reported the first successful results of the inter-molecular cross-metathesis and intramolecular ring-closing metathesis with more reactive ruthenium catalyst for the a-functionalized olefins bearing ester, aldehyde, benzoyl or acetyl group. 

A chiral, non-racemic ruthenium catalyst for asymmetric olefin metathesis. 

RUTHENIUM CATALYSTS FOR RING-OPENING METATHESIS POLYMERIZATION (ROMP) AND RELATED CHEMISTRY... 

Muhlebach, A., van der Schaaf, P.A., Hafner, A., Kolly, R., Rime, F., and Kimer, H.-J. (2001) Ruthenium catalysts for ring-opening metathesis polymerization (ROMP) and related chemistry, NATO ASI Series, this issue. 

Greco, G.E. Nobel Ghemistry in the Laboratory Synthesis of a Ruthenium Catalyst for Ring-Closing Olefin Metathesis. /. Chem. Educ. 2007, 84,1995-1997. 

Stewart IC, Ung T, Pletnev AA, Berlin JM, Grubbs RH, Schrodi Y. Highly Efficient Ruthenium Catalysts for the Formation of Tetrasubstituted Olefins via Ring-Closing Metathesis. Org Lett. 2007 9(8) 1589-1592. 

Keitz BK, Endo K, Patel PR, Herbert MB, Grubbs RH. Improved Ruthenium Catalysts for Z-Selective Olefin Metathesis. J dm Chem Soc. 2011 134(l) 693-699. 

Occhipinti G, Bjorsvik H-R, Jensen VR. Quantitative Structure-Activity Relationships of Ruthenium Catalysts for Olefin Metathesis. J Am Chem Soc. 2006 128(21) 6952-6964. 

Latent Ruthenium Catalysts for Ring Opening Metathesis Polymerization (ROMP)... 

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