Meisenheimer salts

The thiol-diarylsulfide 101 produced a Meisenheimer salt that underwent rearrangement and eventually resulted in the production of 1,3-dinitrothianthrene (75ZOR1440). 

For a monograph on Meisenheimer salts and on this mechanism, see Buncel Crampton Strauss Terrier Electron Deficient Aromatic- and Heteroaromatic-Base Interactions Elsevier New York. 1984. For reviews of structural and other studies, sec Illuminati Stcgcl Adv. Heterocvcl. Chem. 1983,34. 305-444 Artamkina Egorov Bcletskava Chem. Rev. 1982.82. 427-459 Terrier Chem. Rev. 1982, 82. 77-152 Strauss Chem. Rev. 1970, 70. 667-712. Ace. Chem. Res. 1974, 7. 181-188 Hall Poranski. in Fcucr The Chemistry of the Nitro and Niiroso Groups, pt, 2. Wiley New York. 1970. pp. 329-384 Crampton, Adv. Phvs. Org. Chem. i969, 7, 211-257 Foster Fyfe Rev. Pure Appl. Chem. 1966. 16, 61-82. 

A regioselective transformation of quinolines to indoles was developed. The 1,4-dihydro Meisenheimer salts were prepared, to the exclusion of the 1,2-isomer. Yields were poor to excellent <03TL6241>. 

Meisenheimer salt The salt that results from, for example, the reaction between a cyanide anion and 1,3-dinitrobenzene or 1,3,5-trinitrobenzene (at the 2 or 4 positions) in an aprotic solvent such as CHCI3. 

Hz) appears in the aliphatic shift region. This shows that the benzene CH unit rehybridises from trigonal (sp ) to tetrahedral (sp ). so that a Meisenheimer salt A is produced. 

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