Pyrazole is an omnipresent moiety in many natural products and pharmaceutically active compounds. Here, we have developed a simple and dynamic method for one-pot synthesis of substituted pyrazoles through the intramolecular cyclization of hydrazides and alkynyl ketones, using a novel sulfonium saltbased iodate (& Iukcy;) reagent system. This method has the advantage that it proceeds in a one-pot, without isolating a less stable hydrazone intermediate. Hypervalent iodine-based reagents are an environmentally benign and greener option to toxic metal oxidants; they have an extensive application in metal-catalyst-free reactions, and this reaction proceeds in less time with high yields.

Foreign