The behavior toward polyphosphoric acid of arylhydrazones of aromatic carbonyl compounds (anisaldehyde, substituted benzophenones,(4-methoxypheny1) glyoxylic acid esters) and arylaliphatic ketones (4-methoxy-and 4-minoacetophenone) is described. Biphenyl derivatives= e formed through a [5, 5] sigmatropic rearrangement, which often occurs in competition with the expected Fischer indole synthesis and, in the case of the 4- ...
![1-[3-(4-amino-3,5-dimethylphenyl)-4-methoxyphenyl]ethanone Structure](https://image.chemsrc.com/caspic/172/67659-00-1.png)
