2,6-Di(thiazol-4-yl)pyridine
(1a), 2,6-di(2-methylthiazol-4-yl)pyridine (1b) and 2,6-di(2-phenylthiazol-4-yl)pyridine (1c) have been prepared by Hantzsch syntheses from 2,6-di(ω- bromoacetyl )pyridine and the appropriate thioamide. Bis ( ligand ) iron(II) and nickel(II) complexes of (1a) and (1b) have been prepared but no metal complexes of (1c) were isolated. The bis ( ligand ) iron(II) complexes of (1a) are low-spin whereas those of (1b) undergo thermally induced spin-transitions, both in the solid state and solution. The field strengths of the ligands , determined from the spectra of their nickel(II) complexes, correlate well with the observed magnetic behaviour of their iron(II) complexes. The structure of [FeL2][ClO4]2.H2O, L = (1a), was determined by single-crystal X-ray diffractometry . The complex cation has the meridional configuration with the ligand functioning as an approximately planar tridentate. The structural parameters relating to the Fe-N6 coordination sphere are remarkably similar to those found for bis (2,2′:6′, 2′- terpyridine )iron(II) bis ( perchlorate ) monohydrate.
Thermal Reactivity in Metal Organic Materials (MOMs): From Single-Crystal-to-Single-Crystal Reactions and Beyond