1,4-Di(1,2,3-triazol-1-yl)butane as Building Block for the Preparation of the Iron(II) SpinCrossover 2D Coordination Polymer

The novel bidentate ligand 1,4-di(1,2,3-triazol-1-yl)butane (bbtr) reacts with Fe(ClO4)2·6H2O to form the 2D coordination polymer with (3,6) network topology. The {[Fe(bbtr)3](ClO4)2}(infinity) represents an example of spin-crossover material based on 1,2,3-triazole as donor group, and displays an abrupt spin transition accompanied by a thermal hysteresis loop (T1/2(down arrow) = 101 K and T1/2(UP arrow) = 109 K).