Structure, Dynamic Behavior, and Catalytic Activity of a Novel Ruthenium Cyclopentadienyl Complex with a Tridentate P,P,O Ligand

Reaction of 1,2-bis(bis(o-methoxyphenyl)phosphino)ethane (o-MeO-dppe) with [RuClCp(PPh3)2] (1) at 135 °C results in the formation of (η5-cyclopentadienyl)[1-(bis(o-methoxyphenyl)phosphino-κP)-2-((o-methoxyphenyl)(o-phenolato-κO)phosphino-κP)ethane]ruthenium(II) ([RuCp(tappe)]; 3), which constitutes the first example of a ruthenium cyclopentadienyl complex with a tridentate P,P,O ligand. The X-ray structure of 3 has been determined to elucidate its solid-state structure, which shows evidence for a CH/π interaction. An NMR study corroborates this finding, and temperature-dependent 31P and 1H NMR spectra reveal the dynamic behavior of 3 in solution. Complex 3 shows catalytic activity in the isomerization of allylic alcohols to carbonyl compounds.