Abstract
The olefin metathesis reaction, discovered over sixty years ago, is catalyzed by high oxidation state alkylidenes (M=CRR’ complexes) of molybdenum and tungsten. It is arguably the most complicated catalytic reaction outside of complex reactions in biology. Much evidence in the last two decades has suggested that the alkylidenes are formed from Mo(IV) and W(IV) complexes that contain the very olefins that are then metathesized. Details as to how these olefin complexes are turned into alkylidenes have not been elucidated until 2021. I will describe and discuss several ways in which this feat has been accomplished through our research over the past four years.
