Tandem magnetization and post-synthetic metal ion exchange of metal-organic framework: Synthesis, characterization and catalytic study

For the first time, metal-exchange in a magnetic metal-organic framework (MOF) via tandem magnetization and post-synthetic modification has been developed. The new magnetic mixed-metal metal-organic framework nanocomposite, CoFe2O4/[Cu-0.63/Zn-0.37-TMU-17-NH2] (CoFe2O4/[Cu/Zn-MOF]) has been synthesized by immersing the CoFe2O4/Zn-TMU-17-NH2 (CoFe2O4/Zn-MOF) as a template in DMF solution of Cu (II) salts. CoFe2O4/[Cu/Zn-MOF] showed to be a highly reactive and easily recoverable magnetic catalyst for the preparation of tetrazole derivatives via one-pot three-component reactions of different aldehydes with hydroxyl amine hydrochloride and sodium azide. Our results (Fourier transform-infrared, inductively coupled plasma-optical emission spectroscopy, powder X-ray diffraction, field emission-scanning electron microscopy, energy-dispersive X-ray spectroscopy-mapping and vibrating-sample magnetometer) show successful partial metal-exchange in which the framework integrity remained intact during the metal-exchange process.