A new family of spin-crossover complexes based on a [Fe.sup.II][(tetrazolyl).sub.4][(MeCN).sub.2]-type core

The synthesis of a bitopic ligand, 2-hydroxy-1-(tetrazol-1-yl)-3-(tetrazol-2-yl)propane containing 1-substituted and 2-substituted tetrazole rings tethered by a propylene spacer that was functionalized by the incorporation of the hydroxyl group is reported. The complex represents the first example of an iron(II) system with monofunctional tetrazoles possessing the Fe[(tetrazolyl).sub.4][(MeCN).sub.2]-type core and exhibiting a high-spin to low-spin transition.