One-Pot, Three-Component Synthesis of Novel Spiro[3H-indole-3,2′-thiazolidine]-2,4(1H)-diones in an Ionic Liquid as a Reusable Reaction Media

A facile one-pot, three-component protocol for the synthesis of novel spiro[3H-indole-3,2-thiazolidine]-2,4(1H)-diones by condensing 1H-indole-2,3-diones, 4H-1,2,4-triazol-4-amine and 2-sulfanylpropanoic acid in [bmim]PF6 (1-butyl-3-methyl-1H-imidazolium hexafluorophosphate) as a recyclable ionic-liquid solvent gave good to excellent yields in the absence of any catalyst (Scheme1 and Table2). The advantages of this protocol over conventional methods are the mild reaction conditions, the high product yields, a shorter reaction time, as well as the eco-friendly conditions.