Oxorhenium(V) complexes with naphtholate-oxazoline ligands in the catalytic epoxidation of olefins

Four oxorhenium(V) complexes 3a-d equipped with naphtholate-oxazoline based ligands 2a-d have been prepared and characterized by NMR, IR and mass spectroscopy as well as elemental analysis. The molecular structures of complexes 3b and 3d have been determined via single crystal X-ray diffraction analysis and both display a distorted octahedral geometry. Complexes 3a-d are active catalysts for the epoxidation of cyclooctene with tert-butylhydroperoxide (TBHP) showing moderate conversions between 41% and 65%.