Isatin

  Isatin or 1H-indole-2,3-dione is an indole derivative. The compound was first obtained by Erdman^[1] and Laurent^[2] in 1841 as a product from the oxidation of Indigo dye by nitric acid and chromic acids. The compound is found in many plants and Schiff bases of Isatin are investigated for their pharmaceutical properties .^[3]

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It was observed that isatin forms a blue dye if it s mixed with sulfuric acid and crude benzene. The formation of the blue indophenin was long believed to be areaction with benzene. Victor Meyer was able to isolate the substance resposible for this reaction from benzene. This new heterocyclic compound was thiophene. ^[4]

Isatins can be made from the corresponding indole in good yield by a mix of InCl₃ and IBX in a acetonitrile-water solution at 80 °C.^[5]

References

1. ^ Otto Linné Erdmann (1840). "Untersuchungen über den Indigo". Journal für Praktische Chemie 19, (1): 321-362. doi:10.1002/prac.18400190161.
2. ^ Auguste Laurent (1840). "Recherches sur l'indigo". Ann. chim. phys. 3, (3): 393 - 434.
3. ^ Synthesis of 3,3´-[methylenebis(3,1-phenylenenitrilo)]bis[1,3-dihydro]-2H-indol-2-one as a novel bis-Schiff base A. A. Jarrahpour, D. Khalili Molbank 2005, M437 Online Article
4. ^ Ward C. Sumpter (1944). "The Chemistry of Isatin". Chemical Reviews 34, (3): 393 - 434. doi:10.1021/cr60109a003.
5. ^ Yadav, J. S. (2007). "Indium(III) Chloride/2-Iodoxybenzoic Acid: A Novel Reagent System for the Conversion of Indoles to Isatins". Synthesis (5): 693 - 696. doi:10.1055/s-2007-965930.