Direct Observation Of Ru-Alkylidene Forming Into Ethylene In Ring-Closing Metathesis From Hyperpolarized H-1 Nmr

Ring-closing metathesis was monitored using real-time NMR of H-1 hyperpolarized olefins at room temperature. By applying a selective saturation to an observable intermediate, its protons were found to transfer to ethylene. The intermediate was thus identified as a Ru-alkylidene species, which appears in the ethylene formation pathway.