Synthesis of Lophine-Modified Magnetite Nano-LEGO Blocks.

Recently, in order to prevent environmental pollution by nanosized materials, nanosized magnetite, which reversibly disperses and aggregates in a solvent, has been attracting attention because the aggregated particles can be easily collected using a magnet. Here, magnetite nano-LEGO blocks with lophine skeletons on the surface were obtained by the reaction between bromopropyl-modified magnetite nanoparticles and 4-(4,5-diphenyl-1H-imidazol-2-yl)-phenol under the conditions of Williamson ether synthesis. The obtained magnetite nano-LEGO blocks aggregated into fine particles of approximately 280 nm through an oxidation reaction using potassium ferricyanide by forming a lophine dimer skeleton between particles. These submicron-sized fine particles could be easily collected with a magnet at a high yield. Furthermore, nano-LEGO block units could be redispersed in a solvent by irradiating the obtained submicron-sized fine particles with LED light.