Syntheses, Characterization, and X-Ray Crystal Structure of a 1:1 Co-Crystal of bis{bis[((2-(1H-imidazol-2-yl)methylidene)amino)phenolato-κ3N,N’,O]nickel(II)} and bis{bis[((2-(1H-imidazol-2-yl)methylidene) amino)phenol-κ3N,N’,O]nickel(II)} tetra(chloride)

  • Babacar Diop Department of Chemistry, University Cheikh Anta Diop, Dakar 10700, Senegal
  • Gorgui Awa Seck Department of Chemistry, University Cheikh Anta Diop, Dakar 10700, Senegal
  • Ibrahima Elhadj Thiam Department of Chemistry, University Cheikh Anta Diop, Dakar 10700, Senegal
  • Ousmane DIOUF Department of Chemistry, University Cheikh Anta Diop, Dakar 10700, Senegal
  • Farba Bouyagui Tamboura Department of Chemistry, University Alioune DIOP, Bambey, 21400, Senegal
  • Pascal Retailleau Substances Naturelles, CNRS UPR 2301, Université Paris-Sud, Université, Paris-Saclay, 1 av. de la Terrasse, 91198 Gif-sur-Yvette, France
  • Mohamed Gaye Department of Chemistry, University Cheikh Anta Diop, Dakar 10700, Senegal
Keywords: Schiff base, co-crystal, complex, nickel, mononuclear, dinuclear


The present investigation describes the synthesis and structural study of the ligand 2-((1H-imidazol-2-yl)methyleneamino)phenol, which was used to generate three dimensio-nal supramolecular complex formulated as {[Ni(HL)2]2.[Ni(H2L)2]2.(Cl)4.(H2O)5}. The title compound crystallizes in the orthorhombic space group Fddd with the following unit cell parameters: a = 13.9269(4) Å, b = 29.5295(16) Å, c = 43.1739(15) Å, V = 17755.5(12) Å3, Z = 8, R1 = 0.043 and wR2 = 0.129. For this compound, the structure reveals that one neutral mononuclear unit [Ni(HL)2] and one cationic mononuclear unit [Ni(H2L)2]2+. In the neutral unit, the organic molecule acts as a tridentate through one imino nitrogen atom, one nitrogen atom from the imidazole ring and one phenolate oxygen atom. In the cationic unit, it acts as tridentate through one imino nitrogen atom, one nitrogen atom from the imidazole ring and one oxygen atom of non-deprotonated phenol group. In both units the nickel(II) ion is hexacoordinated and the coordination environment can be described as distorted octahedral geometry. Numerous hydrogen bonds link the molecules into three dimensional network.


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How to Cite
Diop, B., Seck, G. A., Thiam, I. E., DIOUF, O., Tamboura, F. B., Retailleau, P., & Gaye, M. (2022). Syntheses, Characterization, and X-Ray Crystal Structure of a 1:1 Co-Crystal of bis{bis[((2-(1H-imidazol-2-yl)methylidene)amino)phenolato-κ3N,N’,O]nickel(II)} and bis{bis[((2-(1H-imidazol-2-yl)methylidene) amino)phenol-κ3N,N’,O]nickel(II)} tetra(chloride). Earthline Journal of Chemical Sciences, 8(2), 257-273.