Synthesis and characterisation of new ditetrazole-ligands as more rigid building blocks of envisaged iron(II) spin-crossover coordination polymers

摘要: Abstract As the ligand system plays most important role in behaviour of spin-transition iron(II) spin-crossover compounds a series eight new mainly bridging di-tetrazole ligands were synthesised and produced insights into spacer modifications as well geometric prerequisites their impact on behaviour. The focus laid aryl-spaced tetrazole ligands, which interesting analogues to well-known alkyl-di-tetrazoles due expected enhanced interaction within molecular structure through π–π-stacking. results this fundamental study yielded further guidelines optimize fine-tune design, are envisaged be used for coordination polymers high T ½ -values with abrupt spin transition Additionally, one SCO compound [μ-Tris(1-[1,1-dimethyl-2-(1 H -tetrazol-1-yl)ethyl]-1 -tetrazole- N 4, 4′)iron(II)] bis(tetrafluoroborate)—[Fe( dtmp ) 3 ](BF 4 2 —is presented. features around 160 K small thermal hysteresis 5 K.