Hydrogenation & Isomerization of Alkenes

Abstract

Alkenes are isomerized by complexes of late, second or third series transition metals. This occurs either by successive β‐hydride abstraction reactions or, more rarely, by a π–allylic mechanism. Both decyclization and annulation reactions of strained, cyclic hydrocarbons are catalyzed by these complexes. Palladium complexes are active catalysts for the Cope‐ and Claisen rearrangements. Homogeneous, catalytic hydrogenation can occur via three possible routes. Ruthenium complexes catalyze transfer hydrogenation. Catalyst modifications can be made to minimize by‐product formation during hydrogenation or deuteriation.