Electronic effects of substituents on the oxidation potentials of vanadyl complexes with tetradentate Schiff base ligands derived from 1,2-propylenediamine

Kinetic study of the oxovanadium(IV)–salen-catalyzed H2O2 oxidation of phenols

“…When this complex is used as the catalyst, higher conversion is achieved, which is explained by the presence of electronreleasing substituents in the ligand. Thus, the higher reactivity observed in our catalytic system in the presence of electron-releasing groups in the salen ligand is similar to the observations of Rayati et al [22] and shares a common origin.…”

“…Hence, formation of the transition state is facilitated by electron-donating groups in both the oxidant and the substrate. Similar results have been reported for the oxidation of cyclooctene and styrene with TBHP in the presence of vanadyl complexes [22]. Rayati et al [22] have reported that the introduction of electron-donating groups on the aromatic rings as well as the imine bonds of salen bases accelerates the reaction effectively.…”

“…The catalytic potential of oxovanadium(IV)-Schiff base complexes derived from 2-hydroxy-3-methoxy-benzaldehyde and 2-hydroxy-4-methoxy-acetophenone with 1,2-propanediamine was tested for the oxidation of cyclooctene and styrene using t-BuOOH as oxidant [22]. The presence of electron-donating substituents on the aromatic ring as well as the imine bond improved the catalytic activity.…”

“…Hammett plot for the oxidation of para-substituted phenols by oxovanadium(IV)-salen-Structure of V(IV) complex used by Rayati et al[22] …”

Catalytic potentials of homodioxo-bimetallic dihydrazone complexes of uranium and molybdenum in a homogeneous oxidation of alkenes

“…High attraction on the high-valent molybdenum(VI) complexes is considerable interest in research due to their catalytic activity as internal catalyst [4] for the oxidation of alkenes and arenes. Many transition metal complexes have been reported for oxidation of alkenes [5][6][7][8][9][10], while dioxomolybdenum Schiff base complexes [4,[11][12][13] have been of great interest due to their ease and low cost in formation, as well as their sterical and electronical structural features. The catalytic oxidation of alkenes by Mo(VI) complexes has been demonstrated by Mimoun et al [14].…”