Metal acetates form diverse polynuclear complexes with 4-amino-3,5-di(2-pyridyl)-1,2,4-triazole (adpt)

Abstract

The reaction of some first-row transition metal acetate salts with 4-amino-3,5-di(2-pyridyl)-1,2,4-triazole (adpt) gives crystals of interesting octa-, tetra-, di- and mononuclear metal complexes with a range of metal–ligand binding modes observed. Specifically, an octanuclear iron complex [Fe₈(adpt^− H)₂(OAc)₁₁(O)₄(OH)₂] was formed, with each deprotonated amine group bridging two iron centres; two different nickel acetate complexes [Ni₂(adpt)(adpt^− H)(OAc)₃(H₂O)] and [Ni(adpt)₂(OAc)₂] co-crystallised in a 2:1 ratio, containing both adpt and adpt^− H ligands and exhibiting several different ligand binding modes, whereas reaction of zinc acetate with adpt gave a tetranuclear complex [Zn₄(adpt)₂(OAc)₆(OH)₂] with the ligand remaining neutral.

Keywords::

• triazole
• polynuclear
• structure
• supramolecular

Acknowledgements

The authors thank the University of Otago for research funding.