Syntheses, Characterization, and X-Ray Crystal Structure of a Co-Crystal Containing One Neutral Mononuclear Copper (II) Unit and One Cationic Dinuclear Copper (II) Unit Assembled with Schiff Base and Perchlorate Copper(II) Salt

  • Ngoné Diouf Department of Chemistry, University Cheikh Anta Diop, Dakar 10700, Senegal
  • Ibrahima Elhadj Thiam Department of Chemistry, University Cheikh Anta Diop, Dakar 10700, Senegal
  • Rokhaya Sylla-Gueye Department of Chemistry, University Cheikh Anta Diop, Dakar 10700, 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, copper, mononuclear, dinuclear


The use of 2-{[2-(2-hydroxybenzylideneamino)phenylimino]methyl}phenol (H2L) in metal transition  chemistry has yielded a co-crystal which is composed by one neutral mononuclear, one cationic dinuclear and one perchlorate anion. During the formation of the complex, one of the salicylaldimine groups of one of the molecules of the H2L ligand hydrolyzed to form an asymmetrical ligand with an amino group leading to the molecule (2-((2-aminophenylimino)methyl)phenol (HL'). The complex was formulated as {[Cu(L)].[Cu2(L)(L')]}.(ClO4). The structure of the complex was solved by single crystal X-ray crystallography. In the mononuclear unit, the Cu2+ atom is coordinated by one dideprotonated  molecule of the ligand acting in tetradentate fashion. In the  dinuclear unit, one the Cu2+ atom is coordinated by one dideprotonated  molecule of the ligand acting in tetradentate fashion and the other Cu2+ is coordinated by the monodeprotonated (2-((2-aminophenylimino)methyl)phenol (HL') acting in tridentate fashion. The two Cu2+ are bridged by the two phenoxo oxygen atoms of the dideprotonated  molecule of the ligand. The complex crystallizes in the triclinic space group Pī with the following parameters: a = 13.8864 (3) Å, b = 14.2078 (4) Å, c = 14.5007 (4)) Å, α = 64.593 (3), β = 71.353 (2), γ = 71.707 (2)°, V = 2395.80 (13) Å3, Z = 2, R1 = 0.037, wR2 = 0.041. The supramolecular structures are consolidated by multiple hydrogen bonds.


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How to Cite
Diouf, N., Thiam, I. E., Sylla-Gueye, R., Retailleau, P., & Gaye, M. (2022). Syntheses, Characterization, and X-Ray Crystal Structure of a Co-Crystal Containing One Neutral Mononuclear Copper (II) Unit and One Cationic Dinuclear Copper (II) Unit Assembled with Schiff Base and Perchlorate Copper(II) Salt. Earthline Journal of Chemical Sciences, 8(1), 35-52.