Cyclic alkyl amino carbene (CAAC) ruthenium complexes as remarkably active catalysts for ethenolysis

An expanded family of ruthenium metathesis catalysis bearing cyclic alkyl amino carbene (CAAC) ligands is reported. These catalysts exhibited exceptional activity in the ethenolysis of the seed oil deriv. Me oleate. In many cases, TONs >100, 000 were achieved, at only 3 ppm catalyst loading. Remarkably, the most active catalyst system was able to achieve a TON of 330, 000, at only 1 ppm catalyst loading. 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 a truly sustainable process for the industrial scale prodn. of linear alpha- olefins (LAOs) and other terminal olefin products.