ABSTRACT
Heterocyclic chemistry is the most interesting branch of organic chemistry and of utmost theoretical and practical importance. Various heterocycles prepared in laboratories are successfully used as clinical agents. Six-membered heterocyclic compounds were synthesized conveniently by catalytic hetero-Diels-Alder reaction. Six-membered aromatic rings possessing two nitrogen atoms including quinazolinones, phthalazinones, pyrimidinones, and pyrimidines, exhibit a wide spectrum of pharmacological properties and therefore they are interesting target compounds in medicinal and pharmaceutical chemistry. Efficient protocols for the preparation of nitrogen (N)-containing heterocycles are of fundamental importance and represent a major challenge in synthetic chemistry. Palladium-catalyzed asymmetric allylic substitution reactions have also emerged as an efficient method for the construction of carbon-carbon and carbon-heteratom bonds. The six-membered carbo- and heterocyclic rings were formed via intramolecular direct arylation of aryl bromides and aryl iodides in the presence of palladium hydroxide/carbon. Functionalized N-heterocycles were synthesized by insertion of carbon monoxide into intermediate aminopalladium adducts.
