Cyclic Alkyl Amino Carbene (CAAC) Ruthenium Complexes as Remarkably Active Catalysts for Ethenolysis

• Published in: Angewandte Chemie (International ed.) Vol. 54; no. 6; pp. 1919 - 1923
• Main Authors: Marx, Vanessa M., Sullivan, Alexandra H., Melaimi, Mohand, Virgil, Scott C., Keitz, Benjamin K., Weinberger, David S., Bertrand, Guy, Grubbs, Robert H.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 02-02-2015; WILEY‐VCH Verlag; Wiley Subscription Services, Inc; Wiley
• Edition: International ed. in English
• Subjects: Carbenes; Catalysis; Catalysts; cyclic alkyl amino carbenes; Decomposition reactions; Derivatives; ethenolysis; Ethylene; Ethylenes - chemistry; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Ligands; Metathesis; Methane - analogs & derivatives; Methane - chemistry; Models, Molecular; olefin metathesis; Ruthenium - chemistry; seed-oil derivatives; terminal olefins; cyclic alkyl amino carbenes; olefin metathesis; terminal olefins; ethenolysis; seed-oil derivatives
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201410797

An expanded family of ruthenium‐based metathesis catalysts bearing cyclic alkyl amino carbene (CAAC) ligands was prepared. These catalysts exhibited exceptional activity in the ethenolysis of the seed‐oil derivative methyl oleate. In many cases, catalyst turnover numbers (TONs) of more than 100 000 were achieved, at a catalyst loading of only 3 ppm. Remarkably, the most active catalyst system was able to achieve a TON of 340 000, at a catalyst loading of only 1 ppm. This is the first time a series of metathesis catalysts has exhibited such high performance in cross‐metathesis reactions employing ethylene gas, with activities sufficient to render ethenolysis applicable to the industrial‐scale production of linear α‐olefins (LAOs) and other terminal‐olefin products.
A new series of olefin‐metathesis catalysts containing cyclic alkyl amino carbene (CAAC) ligands exhibit unprecedented activity in the ethenolysis of methyl oleate. This work advances the state‐of‐the‐art of the ethenolysis reaction and is expected to find particular use in large‐scale industrial applications.