PEG-400 Catalyzed N-C, O-C & C-S Bond Formations: A Robust Sonication Promoted Synthesis of Benzo[d]oxazole-2 (3H)-thione & Benzo[d]thiazole-2(3H)-thione Hybrids

Abstract Herein an efficient and green protocol has been disclosed for the synthesis of biologically competent and structurally simple benzo[d]oxazole-2(3H)-thione/benzo[d]thiazole-2(3H)-thione derivatives. The reaction has been carried out under sonication at 15oC up to 11 hours. Timely progress of the reaction was monitored by using TLC technique. The simple skeletal product with strong biological profile synthesized via simple reaction procedure under complete green conditions is highly useful as per environmental concerns. The unveiled methodology is highly efficient and easy handling as it is devoid of any transition metal catalyst and volatile organic solvent, mostly used for reaction progress. Further, the use of polyethylene glycol, a green catalyst, sonication a selective energy source, better product yield and feasible reaction time are supplementary attributes towards the developed methodology. GRAPHICAL ABSTRACT