AbstractNitriles are known to give rise to salts of different compositions with halogen acids. Many of the reactions undergone by nitriles under the influence of halogen acids are, in many cases, assumed to proceed via the intermediate formation of highly reactive imidoyl derivatives. The intermediates produced, in situ, by the reaction of nitriles with hydrogen chloride should, in principle, be capable of reacting with compounds containing appropriately placed nucleophilic and electrophilic centers leading to the formation of a heterocycle incorporating the C=N of the nitrile. Thus, the reaction of aliphatic, aromatic and heterocyclic nitriles with a variety of ortho aminocarbonyl derivatives such as nitriles, amides, esters and ketones of benzene, thiophen, furan, pyrrole, benzothiophene and pyridothiophene have been found to yield the corresponding condensed pyrimidines in fair to good yields. This constitutes a facile and versatile one‐pot synthesis of condensed pyrimidines.