Octahedral Co(III) complexes of 2-(phenylimino)pyrrolyl ligands: Synthesis and structural characterisation

Synthesis and Structure of 2,5-Bis[N-(2,6-mesityl)iminomethyl]pyrrolylcobalt(II): Evidence for One-Electron-Oxidized, Redox Noninnocent Ligand Behavior

“…Finally, the presence of an intense and well-defined charge transfer band at 410 nm in the UV–vis spectrum is consistent with a metal-to-ligand charge transfer band where a d-based electron in the e orbital is excited into the vacancy in the low-lying π orbital (Figure ). Thus, the assignment as a high-spin d 7 Co­(II) complex of a noninnocent ligand is consistent with X-ray crystallographic metrics, measured values of magnetic susceptibility, EPR, IR, and UV–vis absorption spectra and corroborated by a wealth of existing literature on the geometric behavior of Co­(II) vs Co­(III) coordination complexes. − …”

“…The Co–N Pyr distance greater than 2.0 Å is inconsistent with a Co III –pyrrole anion contact based upon analogous pyrrole– and pyridine–monoimine chemistry. An analysis of reported crystal structures shows that these contacts are closer to 1.9 Å − for Co­(II) complexes and usually less than 1.9 Å for Co­(III) − complexes with iminopyrrolate. The long 2.02 Å contact in the title complex is more consistent with a neutral nitrogen donor to Co­(II).…”

Synthesis and Characterization of Bis(2‐iminopyrrolyl) Iron(II) Complexes by N–H Bond Activation

“…[23] The reaction of CoCl 2 with three equivalents of 2-(phenylimino)pyrrolylsodium salts lead to the formation of the Co III complexes, accommodating three chelating iminopyrrolyl ligands. [24] Alternatively, the complex could be produced through direct N-H bond activation of 2-iminopyrrole by metal precursor. [25][26][27][28] In the coordination chemistry of 2-iminopyrrolyl ligand, iron is in a special situation.…”

“…A similar strategy was used to obtain the five‐coordinate bis(iminopyrrolyl) complexes of cobalt(II) by treatment of CoCl 2 (PMe 3 ) 2 with the corresponding iminopyrrolyl Na salts 23. The reaction of CoCl 2 with three equivalents of 2‐(phenylimino)pyrrolylsodium salts lead to the formation of the Co III complexes, accommodating three chelating iminopyrrolyl ligands 24. Alternatively, the complex could be produced through direct N–H bond activation of 2‐iminopyrrole by metal precursor 25–28…”

Four 1D and 2D Cadmium(II) Complexes Based on Different Anions and Two Modified Bipyridyl Ligands: Syntheses, Structures, Thermogravimetric, and Fluorescent Properties

“…Long lasting endeavors, in coordination chemistry and supramolecular chemistry, were focused on the research of metal‐organic frameworks constructed by nitrogen‐containing ligands 1–4. This is due to the extremely wide range of potential applications reported in various fields, such as homogeneous and heterogeneous catalysis,5 luminescence,6 molecular sieves and size‐selective separation,7 as well as their intriguing network topologies. Attractive configurations of the coordination polymers were found seriously influencing by many aspects, including the coordination nature of metal ions,8 the solvents, organic ligands,9 counter anions,10 crystallization methods,11 pH‐range12 etc.…”