Novel MII (M = Mn, Fe, Co, Ni) Coordination Assemblies Based on 2-(((1-(Pyridin-n-ylmethyl)-1H-1,2,3-triazol-4-yl)methyl)thio)pyridine Ligands

Abstract

© CSIRO 2016.Three novel 1D coordination polymers [M(L1)2(OH2)2(ClO4)2]n (M≤Mn (1), Co (2)) and [Ni(L1)2(OH2)2(NO3)2]n (3), and two mononuclear complexes [Fe(L2)2(MeOH)2(ClO4)2] (4) and [Co(L2)2(OH2)2(ClO4)2] (5) were prepared from 2-(((1-(pyridin-n-ylmethyl)-1H-1,2,3-triazol-4-yl)methyl)thio)pyridine ligands (n≤4 (L1), and 2 (L2)). The complexes 1-5 were characterised by single-crystal X-ray diffraction (XRD), powder XRD, thermogravimetric analysis, elemental analysis, infrared, and electrospray ionisation mass spectrometry analyses. The complexes 1-5 showed good purity and thermal stability. The structural outcome of 1-3 is driven by the double and open-bridging coordination mode preference of the spacer L1 which favours the formation of polymeric 18-member metallomacrocycles. Use of an isomeric L2 with different picolyl nitrogen orientation, which favours chelate formation, resulted in mononuclear complexes 4 and 5. This work demonstrates a simple but powerful spacer-directed strategy to define and construct coordination frameworks tuned by different metal characters and hybrid 1,2,3-triazoles.