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

A facile one‐pot, three‐component protocol for the synthesis of novel spiro[3 H ‐indole‐3,2′‐thiazolidine]‐2,4′(1 H )‐diones by condensing 1 H ‐indole‐2,3‐diones, 4 H ‐1,2,4‐triazol‐4‐amine and 2‐sulfanylpropanoic acid in [bmim]PF 6 (1‐butyl‐3‐methyl‐1 H ‐imidazolium hexafluorophosphate) as a recyclable ionic‐liquid solvent gave good to excellent yields in the absence of any catalyst ( Scheme 1 and Table 2 ). 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.