Synthesis, crystal molecular structure, and magnetic characteristics of coordination polymers formed by Co(ii) diketonates with pentaheterocyclic triphenodioxazines

Abstract

Stable crystalline complexes of Co(II) acetylacetonate [Co(II)(acac)2], trifluoacetylacetonate [Co(II)(tfac)2], and hexafluoroacetylacetonate [Co(II)(hfac)2] with triphenodioxazines (TPDO) were synthesized and their structures studied using X-ray crystallography. In the crystal, complexes [Co(II)(tfac)2]TPDO and...

Synthesis, structure and evaluation of spectral, luminescent and optoelectronic properties of Zn(ii) hexafluoroacetylacetonate complexes of triphenodioxazines

“…The density of the crystals is equal to 1.487 g cm 3 , which is substantially higher than that (1.32 g cm 3 ) of Co(II) complexes 2. 13 The coordination spheres of the Zn centers of Zn(hfac) 2 adduct 5d are similar to those of Zn(hfac) in 4a and 4b, but its crystal packing is different and reveals no p-stacking between the parallel planes of molecules along the a-axis, which is obviously due to the steric hindrance created by four tertbutyl groups of the TPDO ligands. The closest intermolecular contact (atom-plane distance equal to 3.093 Å) is found in the This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2024 crystal between a fluorine atom of hfac and an oxazine fragment of a TPDO ligand.…”

“…S15, ESI †), all studied Zn(hfacac) 2 -TPDO complexes are substantially stable in the solid state, but similar to their Co(II) and Cu(II) analogs. 13,14 The compounds partially dissociate in solution, as shown by changes in the absorption and emission spectra detected under dilution of their solutions.…”

“…11 The structural rigidity of heteropentacenes and the presence in their molecules of two oppositely oriented donor centers (sp 2 nitrogen atoms) impart these compounds with the properties of bridging ligands capable of forming multiple coordination bonds with metal ions to give coordination polymers (CPs) with one-and two-dimensional metal organic frameworks (MOFs). The ability of TPDOs 1 to function as efficient linkers in the formation of 1D CPs has recently been demonstrated by their reaction with Co(II) acetylacetonates 13 (Scheme 1). The strength of these chains is critically dependent on the nature of the metal ion and the type of ligand L. In the case of Co(II) complexes, infinite NÁ Á ÁCoÁ Á ÁNÁ Á Áchains featuring lengthy 1D CP structures 2 are formed only with hexafluoroacetylacetonate (L = hfac) containing electron-accepting trifluoro substituents in the diketonate moieties, whereas the crystal structures of the complexes of acetylacetonate (acac) and trifluoroacetylacetonate (acfac) correspond to the 1 : 1 or 1 : 2 adducts, respectively.…”

“…15 Interesting magnetic properties, particularly strong easy-plane-type magnetic anisotropy, are also demonstrated by Co(II) complexes 2. 13 An earlier study of TPDO metal (d 8 , d 9 ) complexes with open electronic shells 13,14 focused on the investigation of their structural characteristics and magnetic behavior. In the present work, we report the synthesis of diamagnetic Zn(II)-TPDO complexes 4, 5 and exploration of their spectral, luminescent, and electrochemical properties.…”

Field-assisted slow relaxation of magnetization in Cu(ii) complexes with pentaheterocyclic triphenodioxazine ligands: the quasi-one-dimensional versus the binuclear case

“…In 2021, we reported on the synthesis of a novel family of Co( ii ) based 1D coordination polymers 30 formed by Co( ii ) β-diketonates and sterically crowded triphenodioxazines (TPDOs). 31 More recently, a similar reaction between TPDO and Cu(hfac) 2 has been shown to lead to the formation of a unique quasi-one-dimensional Cu( ii ) complex 24 exhibiting slow relaxation of the magnetization in the presence of a rather low applied DC field of 500 Oe, which favorably distinguishes this complex from all other field-induced S = 1/2 SIMs reported to date.…”