title: Biphenyl derived oxovanadium(IV) and copper(II) salen-type complexes--structure and redox tuning.
abstract: A series of vanadyl(IV) salen (N,N'-bis(salicylidene)ethylenediaminato)-type complexes (1-4) bearing phenyl or 2-hydroxyphenyl moieties have been prepared and characterized by means of mass spectrometry, infra-red, electron paramagnetic resonance (EPR), UV/Vis spectroscopy, cyclovoltammetry and X-ray crystallography. Their structures have been compared to their copper(II) analogs 5-8. Hydrogen intralinkages have been observed in the crystal structure of 5. The pendant hydroxy groups fine-tune the redox properties of the complexes. The catalytic activity in the oxygenation of ethyl phenyl sulfide to the corresponding sulfoxide was investigated. Results indicate that complex 1 bearing hydroxyphenyl subunits and a phenylene bridge is the most selective under these reaction conditions, with the smallest amount of the over-oxidized product, sulfone.
authors.affiliation: Anorganisch-Chemisches Institut der Universität Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany. patrick.plitt@urz.uni-heidelberg.de
authors.forename: Patrick
authors.initials: P
authors.lastname: Plitt
authors.forename: Hans
authors.initials: H
authors.lastname: Pritzkow
authors.forename: Thomas
authors.initials: T
authors.lastname: Oeser
authors.forename: Roland
authors.initials: R
authors.lastname: Kraemer