Synthesis of Benzimidazolones and N-phenyl formamides by CO2 fixation Under Mild Reaction Conditions Using Polymer Supported Zinc Complex as Catalyst
Use of formic acid or carbon dioxide as C1 source for the synthesis of medicinally as well as industrially imperative compounds has been gaining predominant attention of synthetic chemists in the current era. This article describes the synthesis of an eco-friendly low cost modified Merrifield supported zinc catalyst [Zn(Meri-Ald-Py)]. Characterization of the newly synthesized catalyst is performed properly by various instrumental techniques like CHN analysis, elemental mapping, FTIR, Energy Dispersive X-Ray analysis, FESEM, TGA, PXRD, N2 adsorption-desorption and AAS (atomic absorption spectroscopy). Benzimidazolones derivatives are synthesized quite efficiently through CO2 fixation in o-phenylenediamine in presence of Zn(Meri-Ald-Py) catalyst at 110°C using 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) under atmospheric pressure. Besides, the synthesized catalyst can effectively produce various N-formylated products from aniline derivatives by utilizing formic acid within very short reaction duration (4.5-20 minutes) at 30°C. Above all, the catalyst is highly heterogeneous in nature and can be used proficiently in several successive cycles.