Butadiene from acetylene–ethylene cross-metathesis†
Acetylene to butadiene direct synthesis, via enyne cross-metathesis, is demonstrated with commercial ruthenium carbene catalysts. Using excess of ethylene, yields greater than 50% are obtained. High activity is observed in the first minute of the reaction (TOF > 800 h−1 based on butadiene). Catalyst reusability and poisoning are discussed.