Synthesis and some transformations of 5-benzotriazolyl-3,4-dihydropyrid-2-ones

5-(Benzotriazolyl)-substituted 3,4-dihydropyrid-2-ones were obtained by condensation of 4-benzotriazolyl-5-phenyl(methyl)-5-oxopentanoic acids with benzyl or aryl amines. Dehydrogenation of 3,4-dihydropyrid-2-ones resulted in 5-benzotriazolyl-substituted pyrid-2-ones and/or 5-(phenylamino)pyrid-2-ones, products of nitrogen elimination from the benzotriazolyl substituent. In turn, 5-benzotriazol-1-yl-substituted pyrid-2-ones eliminated nitrogen under Graebe-Ullmann conditions to give indolopyridones.