Bifunctional Ruthenium(II) PCP Pincer Complexes and Their Catalytic Activity in Acceptorless Dehydrogenative Reactions

New air-stable ruthenium complex 1, bearing the dibenzobarrelene-based
cooperating ligand, was synthesized in 96% yield and fully characterized.
The examination of its coordination chemistry revealed that the ruthenium
center in 1 is slightly distorted from octahedral geometry,
and 31P NMR is consistent with the formation of trans-spanned
pincer complexes bearing strongly bent dibenzobarrelene-based ligands.
The catalytic activity of the new complex was examined in acceptorless
dehydrogenation of alcohols and acceptorless dehydrogenative coupling
of alcohols with amines.