ƞ5-Cyclopentadienyltris-(dialkylphosphito-κ1P) cobaltate(III), (CpPRCo)- was first synthesized by Kläui, and it is often called the Kläui ligand. It has been recognized as a tridentate oxygen analogue of the well-used Tp-(Trispyrazolylborate) ligand. Owing to the ligand's high stability, π-donation capability and weak ligand field strength, organometallic complexes of (CpPRCo)- were found to be quite different from the conventional Tp-based analogs. We have been using (CpPRCo)- as a ligand to make complexes to model the catalytic activity of industrially-used vanadium phosphate oxidation catalysts. Dinuclear organophoshorus-bridged vanadyl complexes with Kläui ligand have been characterized as containing a VO6 octahedral environment for the vanadium center. Our work of late has focused on synthesis and spectroscopic characterization of a series of organometallic complexes with Kläui Ligand (R=OBu); specifically we have generated a series of organo-phosph(on/in)ate-bridged dinuclear vanadium(IV) complexes with the butyloxy group, (CpPOBuCo)2[µ-O2-PR'R"]2 (R', R" = H, OH, Me, Ph, OPh, OPh-NO2, CH3, tBu). To explore the application of these vanadium-Kläui ligand complexes, the catalytic abilities will be investigated by employing 3,5-di-tert-butylcatechol to the corresponding quinone as a model reaction. Our latest results will be present here.
Wu, Xiao, "Synthesis and Characterization of a Series of Vanadium(Iv) Complexes with Kläui Ligand" (2018). University Research Symposium. 164.