Synthesis of two nickel (II) complexes bearing pyrrolide-imine ligand and their catalytic effects on thermal decomposition of ammonium perchlorate

Two pyrrolide-imine chelating Ni(II) complexes {[2-(2-CH3O-C6H4-NCH)C4H3N](2)Ni (2a) and [(Fc-NCH)]C4H3N](2)Ni (2b, Fc = ferrocenyl)} were prepared via treating corresponding Schiff base with 0.5 equiv. NiCl2.6H(2)O in moderate yields. The crystal structures of 2a and 2b were determined by single-crystal X-ray diffraction. Atom Ni(II) of 2a was coordinated by two pyrrolide-imine ligands in trans position to display a twisted octahedral coordination geometry. Ni(II) of 2b had a distorted square-planar geometry, bonded with two ferrocenyl pyrrole-imine ligands, each ferrocene and pyrrole of ligands adopting a trans conformation. The UV-vis spectroscopy and electrochemical measurements were investigated. The catalytic efficiency of the complexes on the thermal decomposition of ammonium perchlorate (AP) was studied by differential scanning calorimetry (DSC) and thermogravimetry (TG). Compared with the thermal decomposition of pure AP, the decomposition temperatures were decreased by 27 degrees C, 77 degrees C, 88 degrees C and 172 degrees C, respectively when 1a, 1b, 2a and 2b were added in AP. The results indicated that the Ni(II) complex 2b bearing ferrocene-based pyrrolide-imine N,N-chelate ligand displayed an excellent catalytic efficiency on the thermal decomposition of AP. (C) 2014 Elsevier B.V. All rights reserved.