Synthesis and recyclization reactions of 4-(o-R-phenyl)-3-imidazolines

Article abstract of DOI:10.1007/BF00717352

1-Hydroxy-4-phenyl-3-imidazoline reacts with butyllithium to give the product of ortho-metallation of the phenyl group.Reactions of this compound with electrophiles followed by oxidation afford 4-(o-R-phenyl) derivatives of nitroxyl radicals.When a hydroxyalkyl group is present in the ortho-position, an unusual pathway of the decay of stable nitroxyl radicals of the imidazoline series has been observed due to the exictence of a spirobicyclic tautomer.The reaction of the o-metallated derivative with CS2 leads to a transformation of the imidazoline ring and to the formation of isoindolethione.Fast recyclization into isoquinolines occurs in the case of the 4-(o-benzoyl)phenyl derivative of 3-imidazoline.The product of o-metallation reacts with methyl nitrate to yield the 4-(o-hydroxy)phenyl derivative (a potential) paramagnetic chelate-forming reagent) and the o-nitro derivative, the starting material for further chemical transformations. - Key words: imidazoline, nitroxyl radical, ortho-matallation, recyclization.