Piperazine core-containing Schiff ligands define chemical reactivity toward divalent metal ions

Publication date: Available online 16 April 2019Source: Inorganica Chimica ActaAuthor(s): Carmen Cretu, Liliana Cseh, Ramona Tudose, Alina Bora, Sevasti Matsia, Antonios Hatzidimitriou, Otilia Costisor, Athanasios SalifoglouAbstractA series of homologous Schiff bases N,N’-bis[(4-decyloxy-salicylideneamino)-n-propyl]-piperazine] (ZOPPH2), and N,N’-bis[(4-dodecyloxy-benzylideneamino)-n-propyl]-piperazine (DBPP)(1), based on 1,4-bis(3-amino-propyl)-piperazine (APPZ), were designed and synthesized, with APPZ serving as the piperazine core, bilaterally flanked by extended alkyl chain-containing antennae. Driven by the pursuit of metallomesogenic materials bearing liquid crystalline state properties, chemical reactivity toward divalent metals Co(II) and Cu(II), in alcoholic or tetrahydrofuran/dimethylsulfoxide media, led to compounds [{Co(ZOPP)}(ClO4)]2.(CH3OH).2(CH3)2SO(2) and [Cu(APPZ)Cl]Cl(3). All materials were characterized by elemental analysis, spectroscopic techniques (UV-Visible, FT-IR, NMR where appropriate), molar conductivity, and X-ray crystallography. Physicochemical characterization emphasizes the a) importance of N,O-containing Schiff anchors in metal ion binding, b) significance of the phenolic moiety, on the flanks of the Schiff ligands, in promoting either metal ion complexation or dissociation of the Schiff base at the azomethine moiety junction, thereby altering metal ion chemical reactivity, and c) observed oxidation of Co(II) to Co(III) upon mononuclear c...

Source: Inorganica Chimica Acta - April 17, 2019 Category: Chemistry Source Type: research