Tolkunov S. Fused derivatives benzofuro[2,3-c]- and benzothieno[2,3-c]pyrilium salts and pyridines. Synthesis and reactions.

The thesis is concerned with the synthesis and the chemical properties study of fused pyrilium and pyridinium salts and pyridinium derivatives of benzofuran, benzothiophene, benzoselenophene. The general procedure towards the synthesis of tri-, tetra- and pentacyclic benzofuro[2,3-c]-, benzothieno[2,3-c]-, and benzoselenopheno[2,3-c]pyrilium salts has been developed. It is based upon the acid catalyzed acylation-heterocyclization. By the interaction of the above mentioned salts with ammonia the novel derivatives of fused benzofuro-, benzothieno- and benzoselenophenopyridines were synthesized. Recyclization reactions of fused pyrilium salts with primary and secondary amines, hydrazine hydrate have also been studied. These reactions led to the formation of the novel derivatives of fused benzofuro-, benzothieno- and benzoselenophenopyridines, dibenzothiophenes and dibenzofuranes, benzothienodiazepines.