A Novel Surfactant Synthesis of BaTi0.85Zr0.15O3 (BTZ): Highly Efficient Catalyst for Synthesis of 1,5-benzodiazepine Derivatives under Solvent-free Conditions

The main objective of this research is to develop efficient and environmentally benign heterogeneous catalysts for synthesis of 1,5-benzodiazepine derivatives. For this purpose, for the first time, heterogeneous BaTi0.85Zr0.15O3 (BTZ) catalyst was prepared by hydrothermal synthesis in the presence of hexadecylamine (HAD) as surfactant, followed by solvothermal method, and the prepared catalyst was characterized by various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 adsorption-desorption, Fourier-transform infrared  (FTIR),Thermogravimetric  (TG-DTG) and Temperature programmed desorption  (NH3-TPD) analysis. BTZ is easily used as a heterogonous, reusable and efficient catalyst for synthesis of 1,5-benzodiazepine by reaction of o-phenylenediamine with different ketones under various conditions. The advantages of this catalytic system is mild reaction conditions, short reaction times, high product yields, easy preparation of the catalysts, non-toxicity of the catalysts, simple and clean work-up of the desired products. Furthermore, the solid catalyst demonstrates long durability for synthesis of 1,5-benzodiazepine derivatives consecutively for at least four cycles under mild conditions.