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

摘要: Abstract A 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 synthesized, with APPZ serving as the piperazine core, bilaterally flanked by extended alkyl chain-containing antennae. Driven pursuit metallomesogenic materials bearing liquid crystalline state properties, chemical reactivity toward divalent metals Co(II) Cu(II), in alcoholic or tetrahydrofuran/dimethylsulfoxide media, led to compounds [{Co(ZOPP)}(ClO4)]2.(CH3OH).2(CH3)2SO(2) [Cu(APPZ)Cl]Cl(3). All characterized elemental analysis, spectroscopic techniques (UV–Visible, FT-IR, NMR where appropriate), molar conductivity, X-ray crystallography. Physicochemical characterization emphasizes a) importance N,O-containing anchors metal ion binding, b) significance phenolic moiety, flanks ligands, promoting either complexation dissociation base at azomethine moiety junction, thereby altering reactivity, c) observed oxidation Co(III) upon mononuclear complex formation. Hybrid DFT calculations DBPP ZOPPH2 suggest increased CH N absence concurrent presence, lending credence notion metal-assisted rupture specific bond emergence metal-ligand product(s). Collectively, data denote structural features piperazine-core antennae ligands transition metals, defining lattice architecture, parameterizing such into synthetic advances new well-defined solid-state physicochemical properties.