A new family of spin-crossover complexes based on a FeII(tetrazolyl)4(MeCN)2-type core

A bitopic ligand 2-hydroxy-1-(tetrazol-1-yl)-3-(tetrazol-2-yl)propane (12pbtzOH) was synthesized and reacted with Fe(CIO4)2 center dot 6H(2)O, giving a 1D coordination polymer {[Fe(12pbtzOH)(2)(CH3CN)(2)](CIO4)(2)center dot 2CH(3)CN}(infinity) that exhibits a high-spin to low-spin transition (T1/2 down arrow = T-1/2 up arrow congruent to 104 K),. This is an unprecedented example of an iron(II) complex containing Fe(tetrazolyl)(4)(MeCN)(2) cores.