Preparation and evaluation of some benzimidazole derivatives as antioxidants for local base oil

Some benzimidazole derivatives, 2(1-H benzo(d)imidazole-2-y1)thio) N-butyl acetamide Ia, 2(I-H benzo(d)imidazole-2-yl)thio) N-octylacetamid Ib and 2(I-H benzo(d)imidazole-2-yl) thio) N-dodecylactamide Ic were prepared and studied as antioxidants for base stock. The structure of these compounds was elucidated by elemental analysis, IR and 1H NMR spectroscopy. The inhibition efficiency of the prepared compounds was determined by studying the oxidation stability of the local base oil via the change in total acid number (TAN), viscosity and infrared (IR) spectroscopy.