Cu(II) and Co(II) Schiff‐Base Complexes Immobilized on Layered Double Hydroxide: Synthesis, Characterizations, DFT Calculations and Catalytic Activity
Jagat Singh Kirar, Savita Khare, Neha Tiwari
Abstract
Abstract In this study, we are reporting the synthesis, characterization, theoretical studies, and catalytic activity of Cu(II), and Co(II) Schiff base complexes immobilized on layered double hydroxide abbreviated as LDH‐[NAPABA‐M] {where M=Cu(II), and Co(II)}. The Schiff base ligand (E)‐4‐((2‐hydroxynaphthalen‐1‐yl)methyleneamino)benzoic acid have been synthesized from the condensation of 2‐hydroxy‐1‐naphthaldehyde and 4‐amino benzoic acid. The complexes were characterized using Inductively coupled plasma‐Atomic emission spectrometry (ICP‐ AES), X‐Ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X‐Ray (EDX), Fourier transform infrared (FTIR), Electron paramagnetic resonance (EPR) spectroscopy, Thermogravimetric analysis (TGA) etc. and the geometry of the ligand has been calculated using Density Functional Theory (DFT) calculations at the B3LYP/6‐31G level of theory. The catalytic activity of synthesized catalysts was tested for toluene oxidation with tert ‐butyl hydroperoxide under solvent‐free conditions. The LDH‐[NAPABA‐Cu(II)] catalyst was recycled up to seven cycles. Hot filtration experiments demonstrate that the catalyst was heterogeneous in nature and stable.