MOLECULAR-REARRANGEMENTS .14. PHOTOLYSIS AND THERMOLYSIS OF PHENYLPROPIONANILIDES

Photolysis and thermolysis of phenylpropionanilide and (o-methylphenyl)- and (p-methylphenyl)propionanilides gave the corresponding arylamine, 1,4-diphenylbutane, together with ortho and para (α-phenethyl)arylamine. The first step in such a process is the homolysis of the acyl-N bond into arylamino and phenylpropionyl free radicals. The latter undergo decarbonylation into β-phenethyl radicals which rearrange to their α isomers. Photolysis was found to be an intramolecular process, while thermolysis was found to be mainly intermolecular as shown by cross-over experiments. On the other hand, alkyl derivatives of the solvent were isolated when the anilides were pyrolyzed in the presence of β-naphthol or isoquinoline as aromatic solvents. © 1979, American Chemical Society. All rights reserved.