Catalytic homogeneous CH-activation reactions of cyclooctane with [Ir(cod)LL]X complexes (LL = N, N-chelating ligands, amines, phosphines; X = Cl, PF 6)

Abstract

A series of new [Ir(cod)LL]X complexes (LL = chelating ligands, amines, phosphines; X = Cl, PF 6) was synthesized. The complexes catalyzed the selective homogeneous dehydrogenation of cyclooctane to give cyclooctene up to a rate of 61 turnovers. The activity and selectivity depends on the ligand structure of the corresponding coordination compound. The addition of external additives (amines and phosphines) increased the activities up to 100% in case of PCy 3 and NHPh 2. The dehydrogenation reaction showed a high temperature dependence.