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One pot green synthesis of 1-(1,2,4-triazol-4-yl)spiro[azetidine-2,3′-(3H)-indole]-2′,4′(1′H)-diones was carried out by the reaction of indole-2,3-diones,4-amino-4H-1,2,4-triazole and acetyl chloride/chloroacetyl chloride in ionic liquid [bmim]PF6 with/without using a catalyst. It was also prepared by conventional method via Schiff's bases, 3-[4H-1,2,4-triazol-4-yl]imino-indol-2-one. Further, the corresponding phenoxy derivatives were obtained by the reaction of chloro group attached to azetidine ring with phenols. The synthesized compounds were characterized by analytical and spectral (IR, 1H NMR, 13C NMR, and FAB mass) data. Evaluation for insecticidal activity against Periplaneta americana exhibited promising results.

Studies on the title reaction in different media indicate that ionic liquid [bmim]PF6 is a good solvent to achieve spiro[indole-pyrazole] (III) in excellent yield.

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 (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.

Diones (I) are treated with amino substrates (II), (IV) or (VI) to form the different heterocyclic systems shown.

The azomethine ylide, generated in situ by decarboxylative condensation of isatin with sarcosine, undergoes 1,3-dipolar cycloaddition with dipolarophiles (I) in ionic liquid to give novel dispiro heterocycles with high regio- and stereoselectivity.

A new reagent N-hydroxy-N-(o-chlorophenyl)-N′-(p-methoxyphenyl)benzamidine hydrochloride, has been synthesized and is characterized on the basis of mp, elemental analysis, IR and UV spectra. The reactions of the reagent with metal ions suggest that new methods can be developed for gravimetric and extraction spectrophotometric determination of metal ions. The reagent has been successfully used for the extraction-spectrophotometric determination of vanadium(V) in presence of phenol. Many common ions including Co2+, Zn2+, Ag+, Mn2+, etc. do not interfere in the determination. The method has been applied for the determination of vanadium in steel samples.