Syntheses, structures and magnetic properties of Fe6 and Fe12 ferric wheels

Abstract

Starting from the same Fe3O(RCO2)6 complex and using a similar synthesis strategy, the Fe6and Fe12 wheels were obtained by utilizing two designed ligands, 2-amino-2-methyl-1,3-propanediol (L1) and 1,3-propanediol (L2), respectively. A biological buffer reagent, Bis-Tris (2-[bis-(2-hydroxyethyl)amino]-2-(hydroxymethyl)propane-1,3-diol) was first introduced in the synthesis of the Fe12 wheel, playing a vital role in adjusting the acidity of reaction environment. Magnetic studies on both Fe6 and Fe12 wheels revealed strong antiferromagnetic coupling between the spins on FeIII ions.