Synthesis and characterization of a new (E,E)-dioxime and its mono and polynuclear complexes containing a 14-membered dithiadiaza macrocyclic moiety

Abstract

A novel (E,E)-dioxime,5,6:13,14-di(4′-t-butylbenzo)-2,3-bis(hydroxyimino)-8,11-dithia-1,4-diazacyclotetradecane (H₂L), containing a 14-membered dithiadiaza macrocyclic unit has been synthesized by the reaction of 1,2-bis(4-t-butyl-2-aminobenzylthio)ethane (1) and cyanogendi-N-oxide (2). A mononuclear nickel(II) complex (3) with a metal : ligand ratio of 1 : 2 was also prepared. A heterotrinuclear complex [Cu₂Ni(HL)₂](PF₆)₂ (4) was synthesized by using the mononuclear complex 3 and [Cu(CH₃CN)₄]PF₆. A heteropentanuclear complex [Cu₂(UO₂)₂(phen)₂Ni(HL)₂](PF₆)₂(NO₃)₂ (5) containing the oximato tetraanion as a bridging ligand and 1,10-phenanthroline as an end-capping ligand was obtained by using the heterotrinuclear ligand for the Cu₂

center. The ligand and its complexes have been characterized by ¹H and ¹³C NMR, IR and mass spectroscopy, elemental analysis and semiempirical quantum chemical calculations.

Keywords:

• (E,E)-Dioxime
• N2S2-Donor macrocycle
• Heterotrinuclear complex
• Heteropentanuclear complex
• [UO2]2+
• Ni(II)
• Cu(I)

Acknowledgments

This work was supported by the Research Fund of Karadeniz Technical University, Project number: 2002.111.2.8 (Trabzon, Turkey). We are also indebted to Dr Ayhan Celik (University of Edinburgh, UK) for his assistance with the MS data.