Ferrocene-bis(phosphinimine) Nickel(II) and Palladium(II) Alkyl Complexes: Influence of the Fe–M (M = Ni and Pd) Interaction on Redox Activity and Olefin Coordination

Abstract

The synthesis of several novel nickel(II) and palladium(II) ferrocene-bis(phosphinimine) alkyl complexes containing iron-nickel and iron-palladium interactions is reported. The redox behavior of all complexes was evaluated electrochemically and chemically; in addition, reactions with weak nucleophiles, such as acetonitrile and olefins, were also investigated. DFT calculations were performed to understand the electronic structure of the alkyl metal complexes.

Exploring Oxidation State-Dependent Selectivity in Polymerization of Cyclic Esters and Carbonates with Zinc(II) Complexes

“…However, in the case of the reduced species, a direct zinc-phosphine interaction was not observed. Despite this finding, and because of our interest in redox-switchable catalytic processes ( Abubekerov et al., 2016 , Abubekerov et al., 2017 , Wang et al., 2014 , Wang et al., 2015 , Quan and Diaconescu, 2015 , Brosmer and Diaconescu, 2015 , Abubekerov and Diaconescu, 2015 , Upton et al., 2014 , Broderick et al., 2011a , Broderick et al., 2011b , Broderick et al., 2011c , Quan et al., 2016 , Quan et al., 2017 , Lowe et al., 2017 , Shepard and Diaconescu, 2016 ), we set out to investigate the influence of the redox state of fc P,B on the zinc-mediated ring-opening polymerization of cyclic esters and carbonates. In addition, an investigation into the redox and polymerization activity of a monomeric ferrocene-chelating heteroscorpionate zinc complex, (fc P,B )Zn(OPh), is reported.…”

Recent Progress in Decoupled H2 and O2 Production from Electrolytic Water Splitting

“…Overall, the electrolyte pH was not buffered and fluctuated between 6.5 and 9. Since a rich library of ferrocene derivatives could be readily synthesized with a broad range of redox potential, it is anticipated that ferrocene derivatives can utilized for decoupled electrolysis of not only water splitting but also many other redox reactions …”

Beyond Common Metal–Metal Bonds, κ3‐Bis(donor)ferrocenyl→Transition‐Metal Interactions

“…The ferrocenyl moiety is, however, primarily used as a structural component however there are limited examples of a Fe→TM bond found with metals containing organometallic ligands relevant for catalysis or such complexes playing a role in catalysis . The organometallic nickel and palladium alkyl complexes containing ferrocene‐bis(phosphinimine) [Fe(C 5 H 4 NPPh 3 ) 2 ] were synthesized from [PdClMe(PPh 3 ) 2 ] or [NiClPh(PPh 3 ) 2 ], NaBPh 4 , and the ferrocenyl ligand (Scheme ) to form [ 14 ] + and [ 15 ] + respectively . The molecular structures of both [ 14 ] + and [ 15 ] + show ferrocenyl ligand distortion consistent with a Fe→TM bond.…”

“…[29] The organometallic nickel and palladium alkyl complexes con- respectively. [30] The molecular structureso fb oth [14] [14] + + ,w hich prevented both these complexes from being useful as ac atalyst in ac ross-coupling reaction. Additionally,e xternal stimuli resulted in decompositionf urther hamperingt heir use in any type of redox-activated catalysis.…”

“…Additionally,e xternal stimuli resulted in decompositionf urther hamperingt heir use in any type of redox-activated catalysis. [30] The catalytically active species[ PdBr(Ar)(dtbpf)] ([16Br]) was generated througho xidativea ddition of ArBr to Pd 0 speciesi n the presenceo fd tbpf. The Br À ligand in [16Br] was displaced by the formation of aF e !Pd bond in polar solvents to form [16]Br.T he formation of the Fe dative bond, however,i nhibits the reactivity of [16Br] toward transmetallation and therefore the catalystdoes not react any furtherinthe reductiveelimination of diaryl ethers( Scheme12).…”