Synthesis and structure characterization of metal-organic frameworks with a triple iron helical complex

Metal-organic frameworks were achieved from triple metal helical iron complex [(Fe2L3)(.)(H2O)(4)] (L = bis[2-hydroxybenzaldehyde]hydrazonate). The phenyl rings of the helical units contact the neighbors via pi-pi and C-H... pi interactions to form two-dimensional channeled frameworks in which four solvent water molecules are included in the channels of the structure. Thermogravimetric analyses reveal that the solvent water molecules can be evacuated from the pores without loss of the framework periodicity. The crystal lattice is thermally stable up to 339.9 degrees C, and water can be re-included by putting the heated material in water.