Extensive isomerization of alkenes using a bifunctional catalyst: An alkene zipper

Catalyzed movement of alkene double bonds up to 30 positions has been accomplished using a catalyst featuring a cationic CpRu fragment and bifunctional imidazolylphosphine. The basic nitrogen of the latter is thought to deprotonate coordinated alkene intermediates reversibly, facilitating isomerization between terminal and (E)-alkenes and accelerating conversions by factors of up to 1 x 10(4).