Synthesis of butadiene via vinyl–ethylene combination at a diruthenium centre
Abstract
Treatment of the µ-vinyl cation [Ru2(CO)(McCN)(µ-CO)(µ-CHCH2)(η-C5H5)2]+ with ethylene (1 atm, 25 °C) gives two isomers of [Ru2(CO)2(µ-H)(µ-CH2CHCHCH2)(η-C5H5)2]+, containing (S)-cis- or (S)-trans-butadiene; deprotonation is effected with KOH/ethanol to afford the neutral (S)-trans-butadiene complex [Ru2(CO)2(µ-CH2CHCHCH2)(η-C5H5)2].