Organo‐Phosph(on/in)ate‐Bridged Dimers of Vanadium(IV) Complexes with the Kläui Ligand: Synthesis and Characterization

Abstract

A series of dinuclear organophosphorus‐bridged vanadium(IV) complexes with the Kläui ligand, [CpPOMeCo]–, have been synthesized to model the catalytic activity of industrially used vanadium phosphate oxidation catalysts. Dimeric species of the general formula [(CpPOMeCo)V(O)(μ‐O2PR′R″)]2 (R′,R″ = H, OH, Me, Ph, or 4‐OPh‐NO2), [(CpPOMeCo)V(O)]2(μ‐oxalate), and [(CpPOMeCo)V(Cl)]2(μ‐oxalate) are reported. These complexes have been characterized via spectral and magnetic analyses. The synthesis, characterization, and X‐ray structures of the mononuclear vanadium(IV) complexes (CpPOMeCo)V(O)Cl(OH2) and(CpPOMeCo)V(O)(acac) are also presented here. [CpPOMeCo]–= η5‐cyclopentadienyltris(dimethylphosphito‐κ1P)cobaltate(III); acac = acetylacetonate.

Anionic phosph(in)ito (“phosphoryl”) ligands: Non-classical “actor” phosphane-type ligands in coordination chemistry

“…7). These complexes have been characterized via spectral and magnetic analyses and their structures determined by X-ray analyses [155]. Metal-mediated C−H amination coupled with cyclometalation of an alkylbenzene was first reported by ruthenium−imido catalysts 109 incorporating the  1 -P−phosphonate Klaüi tripodal ligand (Fig.…”

A journey into the electrochemistry of vanadium compounds

“…The complexes uniformly exhibited a quasi-reversible cyclic voltammetric response in DCM solution (Table 1, entries [50][51][52][53][54][55][56][57].…”

“…A cathodic shift of the potential was observed with the increasing electron donating ability of the substituents. With salhyac and achyac ligands a dioxido-V(V) complex was also prepared [161] both complexes are electroactive in MeOH, with irreversible reduction peak ( Table 5, entries [49][50][51].…”

“…A series of dinuclear organophosphorus-bridged oxido-V(IV) complexes with the Kläui ligand, [Cp POMe Co] − , have been synthesized to model the catalytic activity of industrially used vanadium phosphate oxidation catalysts [50]. The dinuclear complexes had either an oxalate or a phosphonate/phosphinate bridge, with different substituents.…”

Synthesis, Characterization, and Electrochemical Analyses of Vanadocene Tetrametaphosphate and Phosphinate Derivatives

“…While several heterogeneous and homogeneous VPO model complexes have been synthesized in order to elucidate the reaction mechanism, 22-31 the vast majority of these contain vanadyl (V=O) linkages hindering the ability to distinguish V=O from terminal P=O bond reactivity (Scheme 1c). 30,[32][33][34][35] In the cases where V=O is absent, bimetallic species bridged by -OPR2O-linkers dominate, with very few having terminal P=O bonds present. 36 In order to probe possible new C-H bond functionalization pathways, such as the proposed ROA mechanism, new VPO model complexes are needed containing terminal P=O linkages bound to encapsulated V centers.…”