Benzimidazole Ligands

Haga, Masa‐aki

doi:10.1016/b0-08-043748-6/01095-1

Cited by 8 publications

(2 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[12][13][14] For this reason, imidazole groups are incorporated in ligand scaffolds as their N-methyl derivative. Other derivatives, such as benzimidazole [15][16][17] or bisimidazoline [18] have also been used to tackle the same issue, that is to say the tuning of the redox properties coupled with remote proton abstraction.…”

Section: Introductionmentioning

confidence: 99%

Proton‐Mediated Redox Control in a Nickel(II)–Bisimidazolate Complex: Spectroscopic Characterisation and Density Functional Analysis

Lassalle‐Kaiser¹,

Guillot²,

Sainton³

et al. 2008

Chemistry A European J

View full text Add to dashboard Cite

The synthesis and characterisation of the pro-ligand LH4, in which L is the o-phenylenebisamide-2-imidazole and its nickel(II) complexes are reported. The X-ray structures of the fully protonated [NiLH2] and deprotonated [NiL] complexes are presented. The effects of the deprotonation of the imidazole functions on the electronic structure of the complexes are analysed by (1)H NMR, UV/Vis and IR spectroscopy and cyclic voltammetry. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations support the analysis based on experimental data. The singly oxidised form of the deprotonated complex [NiL] was generated by preparative electrolysis and its electronic structure was investigated. Spectroelectrochemistry shows the appearance of intense transitions in the region lambda = 600-900 nm with several isosbestic points. X-band EPR spectroscopy presents an isotropic signal at g = 2.03, whereas the Q-band EPR reveals a weak anisotropic signal characteristic of a metalloradical species. DFT and TDDFT data support the description of the species as a nickel(II)-radical form, with a major contribution of the spin density on the phenylene ring and the amidate functions with a negligible participation of the imidazolate groups. This finding is in sharp contrast with those obtained from the one-electron-oxidised form of nickel(II) complexes containing phenolate groups.

show abstract

Section: Introductionmentioning

confidence: 99%

Proton‐Mediated Redox Control in a Nickel(II)–Bisimidazolate Complex: Spectroscopic Characterisation and Density Functional Analysis

Lassalle‐Kaiser¹,

Guillot²,

Sainton³

et al. 2008

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…They tend to be very robust and remain stable under considerable thermal and chemical stress − In addition, removal of the imidazole proton allows pH control of the electron density on the conjugated ligands. − …”

Section: Introductionmentioning

confidence: 99%

Efficient Synthesis and Characterization of Novel Bibenzimidazole Oligomers and Polymers as Potential Conjugated Chelating Ligands

Yin

Elsenbaumer

2005

J. Org. Chem.

View full text Add to dashboard Cite

[Structure: see text]. A simple and mild condensation route for the synthesis of novel bibenzimidazole oligomers and polymers is reported here using methyl 2,2,2-trichloroacetimidate as a key starting material. The dimer, trimer, tetramer, and polymers of bibenzimidazole were synthesized as a new series of potential conjugated chelating ligands for metallopolymer studies. The polymers show a maximum absorption at around 400 nm. The optical band gap of the polymer was estimated to be 2.68 eV.

show abstract