A half-salamo-based pyridine-containing ligand and its novel Ni^II complexes including different auxiliary ligands: syntheses, structures, fluorescence properties, DFT calculations and Hirshfeld surface analysis

Abstract

Three novel multinuclear NiII complexes, namely, bis{μ-2-methoxy-6-[8-(pyridin-2-yl)-3,6-dioxa-2,7-diazaocta-1,7-dien-1-yl]phenolato}bis[thiocyanatonickel(II)], [Ni2(L)2(NCS)2], 1, bis{μ-2-methoxy-6-[8-(pyridin-2-yl)-3,6-dioxa-2,7-diazaocta-1,7-dien-1-yl]phenolato}bis[azidonickel(II)], [Ni2(L)2(N3)2], 2, and catena-poly[[{2-methoxy-6-[8-(pyridin-2-yl)-3,6-dioxa-2,7-diazaocta-1,7-dien-1-yl]phenolato}nickel(II)]-μ-dicyanamidato], [Ni(L)(dca)] n , 3 {dca is dicyanamide, C2N3, and HL is 2-methoxy-6-[8-(pyridin-2-yl)-3,6-dioxa-2,7-diazaocta-1,7-dien-1-yl]phenol, C16H17N3O4}, with a half-salamo-based pyridine-containing HL ligand have been synthesized and characterized by FT–IR, UV–Vis absorption spectroscopy, X-ray crystallography, Hirshfeld surface analysis and density functional theory (DFT) calculations. The central NiII ions in complexes 1–3 are hosted in the half-salamo-based N3O-donor cavity of the organic ligand. Complex 1 is a centrosymmetric dimer and two [Ni(L)(NCS)] units form a centrosymmetric dimeric structure, which is bridged by two phenolate O atoms. The two N atoms at the axial ends are provided by two NCS− ligands. In complex 1, each NiII ion has a six-coordinated octahedral geometry. Complex 2 is similar to 1, but they differ in that the auxiliary NCS− ligand is replaced by N3 −. However, complex 3 is a one-dimensional coordination polymer constructed from [Ni(L)(dca)] units, which are connected by the auxiliary bidentate dca ligand via N-donor atoms. As with complexes 1 and 2, the NiII ion in 3 has a six-coordinated octahedral geometry.

Exploring two helical centrosymmetric homotetranuclear Cu (II) bis (salamo)‐based complexes

“…The energy gap (ΔE = Δ LUMO ‐Δ HOMO ) is also an important factor to likely influence the stability and reactivity of the complexes. For the complex, the lower value of ΔE represents more stable and reactivity, and the higher value of ΔE shows softness or hardness of the complexes 67 …”

Exploitation of a Half-Conjugate Polydentate Salamo–Salen Hybrid Ligand and Its Two Phenoxide-Bridged Heterohexanuclear 3d–s Double-Helical Cluster Complexes

“…Zhang et al developed bioinspired single-chain polymeric nanoparticles with a chiral Salen-Ti IV complex that were used as an enzyme-mimetic catalyst to realize the enantioselective oxidation of different sulfides in water (H 2 O) . To date, a lot of Salamo-type compounds derived from Salen have found potential applications within the fields of nonlinear-optical materials . Among them, Akine and colleagues described that the introduction of different benzocrown substituents to the trisalamo ligand system realizes the helicity control and helix inversion of two helical isomers (left- or right-handed) in the coordination process of metal ions .…”

“…15 To date, a lot of Salamo-type compounds 16 derived from Salen have found potential applications within the fields of nonlinear-optical materials. 17 Among them, Akine and colleagues described that the introduction of different benzocrown substituents to the trisalamo ligand system realizes the helicity control and helix inversion of two helical isomers (left-or right-handed) in the coordination process of metal ions. 18 Schmid et al reported that several Salen complexes based on a hybrid ligand system could behave as homogeneous catalysis for the 1,4-addition reaction of an oxindole to produce a nitroolefin.…”

An investigation of structure, Hirshfeld surface, and fluorescence properties of two dinuclear Ni (II) and Zn (II) salamo‐type complexes

“…[ 22–30 ] Due to the electronegativity of the oxygen atoms, which can significantly affect the reversible reaction of the imine bond, salomo‐based compounds with specific functions [ 31–37 ] and novel structures were synthesized. [ 38–45 ] With the continuous deepening and expansion of their research, a lot of 3d, [ 46–50 ] 3d‐s, [ 51 ] 3d‐4f [ 52–55 ] complexes have been synthesized by coordination‐driven self‐assembling, at the same time, the fast and efficient chemical probes have also been developed. [ 56–59 ]…”