Impact of NHC ligand conformation and solvent concentration on the ruthenium-catalyzed ring-closing metathesis reaction

Journal of the American Chemical Society

Volumn 131, Issue 27, 2009, Pages 9498-9499

  Gatti, Michele ^a   Vieille Petit, Ludovic ^a   Luan, Xinjun ^a   Mariz, Ronaldo ^a   Drinkel, Emma ^a   Linden, Anthony ^a   Dorta, Reto ^a  

^a UNIVERSITY OF ZURICH   (Switzerland)

Author keywords

[No Author keywords available]

Indexed keywords

CATALYST LOADINGS; N-HETEROCYCLIC CARBENE LIGANDS; NHC LIGANDS; PRECATALYSTS; RING-CLOSING METATHESIS REACTIONS; RUTHENIUM METATHESIS; SIDE CHAINS; SOLVENT CONCENTRATION; X-RAY DIFFRACTION STUDIES;

CATALYSIS; CATALYSTS; LIGANDS; RUTHENIUM;

RUTHENIUM COMPOUNDS;

CARBENOID; HETEROCYCLIC COMPOUND; LIGAND; RUTHENIUM COMPLEX;

ARTICLE; CATALYSIS; COMPLEX FORMATION; CONFORMATION; PROTON NUCLEAR MAGNETIC RESONANCE; RING CLOSING METATHESIS;

EID: 67650468437     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja903554v     Document Type: Article

References (26)

1. (a) Trnka, T. M.; Grubbs, R. H. Acc. Chem. Res. 2001, 34, 18.
2. (b) Grubbs, R. H. Handbook of Metathesis; Wiley-VCH: Weinheim, Germany, 2003.
3. HovII: (a) Garber, S. B.; Kingsbury, J. S.; Gray, B. L.; Hoveyda, A. H. J. Am. Chem. Soc. 2000, 122, 8168.
4. BleII: (b) Wakamatsu, H.; Blechert, S. Angew. Chem., Int. Ed. 2002, 41, 2403
5. GreII: (c) Grela, K.; Harutyunyan, S.; Michrowska, A. Angew. Chem., Int. Ed. 2002, 41, 4038
6. LAGII: Bieniek, M.; Bujok, R.; Cabaj, M.; Lugan, N.; Lavigne, G.; Arlt, D.; Grela, K. J. Am. Chem. Soc. 2006, 128, 13652.
7. (a) Luan, X.; Mariz, R.; Gatti, M.; Costabile, C.; Poater, A.; Cavallo, L.; Linden, A.; Dorta, R. J. Am. Chem. Soc. 2008, 130, 6848.
8. (b) Vieille-Petit, L.; Luan, X.; Mariz, R.; Blumentritt, S.; Linden, A.; Dorta, R. Eur. J. Inorg. Chem. 2009, 1861.
9. (c) Vieille-Petit, L.; Luan, X.; Gatti, M.; Blumentritt, S.; Linden, S.; Clavier, H.; Nolan, S. P.; Dorta, R. Chem. Commun. 2009, 3783.
10. Similar NHCs with unsymmetrical phenyl side chains are fluxional, see: Stewart, I. C.; Benitez, D.; O'Leary, D. J.; Tkatchouk, E.; Day, M. W.; Goddard, W. A.; Grubbs, R. H. J. Am. Chem. Soc. 2009, 131, 1931.
11. Such systems might show differences in catalytic performance and could serve as ideal models for studying some of the mechanistically relevant and still disputed steps of metathesis reactions; see: (a) Romero, P. E.; Piers, W. E. J. Am. Chem. Soc. 2005, 127, 5032.
12. (b) Wenzel, A. G.; Grubbs, R. H. J. Am. Chem. Soc. 2006, 128, 16048.
13. (c) Romero, P. E.; Piers, W. E. J. Am. Chem. Soc. 2007, 129, 1698.
14. (d) Van der Eide, E. F.; Romero, P. E.; Piers, W. E. J. Am. Chem. Soc. 2008, 130, 4485.
15. See the Supporting Information for details.
16. The results seem counterintuitive given the overall higher steric bulk of (2,7)-SIPrNap and (2)-SICyNap compared to SIMes (ref 3a).We believe that this is due to the fact that one of the sides on the naphthyl moieties is more open than in SIMes and, as a consequence, bulky substrates can approach the metal center more easily.
17. To our knowledge, this is the first study relating reactivity to reaction concentration since productive RCM was introduced. Early studies on substrates such as 5 with less selective/active Schrock's and Grubbs' I catalysts showed that productive RCM needed dilutions of at least 0.1 M; see: (a) Forbes, M. D. E.; Patton, J. T.; Myers, T. L.; Maynard, H. D.; Smith, D. W.; Schulz, G. R.; Wagener, K. B. J. Am. Chem. Soc. 1992, 114, 10978.
18. (b) Kirkland, T. A.; Grubbs, R. H. J. Org. Chem. 1997, 62, 7310.
19. For more recent relevant reports, see: (c) Dinger, M. B.; Mol, J. C. Adv. Synth. Catal. 2002, 344, 671.
20. (d) Dolman, S. J.; Sattely, E. S.; Hoveyda, A. H.; Schrock, R. R. J. Am. Chem. Soc. 2002, 124, 6991.
21. (e) Maifeld, S. V.; Miller, R. L.; Lee, D. J. Am. Chem. Soc. 2004, 126, 12228.
22. For insightful recent studies on solvent concentration in macrocyclic RCM: (a) Conrad, J. C.; Eelman, M. D.; Silva, J. A. D.; Monfette, S.; Parnas, H.; Snelgrove, J. L.; Fogg, D. E. J. Am. Chem. Soc. 2007, 129, 1024.
23. (b) Shu, C.; Zeng, X.; Hao, M.-H.; Wei, X.; Yee, N. K.; Busacca, C. A.; Han, Z.; Farina, V.; Senanayake, C. H. Org. Lett. 2008, 10, 1303.
24. Grela and more recently Grubbs showed that high TONs can be achieved when heating 5 in toluene with HovII. However, already 7 gives much poorer results: (a) Bieniek, M.; Michrowska, A.; Usanov, D. L.; Grela, K. Chem. - Eur. J. 2008, 14, 806.
25. (b) Kuhn, K. M.; Bourg, J.-P.; Chung, C. K.; Virgil, S. C.; Grubbs, R. H. J. Am. Chem. Soc. 2009, 131, 5313.
26. Luan, X.; Mariz, R.; Robert, C.; Gatti, M.; Blumentritt, S.; Linden, A.; Dorta, R. Org. Lett. 2008, 10, 5569.