N-3-Oxoalkylamides and -Thioamides in the Synthesis of Heterocyclic Compounds. 7. Study of the Cyclization of N-(3-Oxoalkyl)amides of Tosylacetic Acid

Alkyl-substituted N-(3-oxoalkyl)amides of tosylacetic acid are cyclized under the action of bases with the formation of 3-tosyl-3,6-dihydropyridin-2(1H)-ones. In the presence of a phenyl substituent at position C₍₁₎ of the 3-oxoalkyl chain the reaction proceeds with the formation of 2-pyridones. The principles influencing the regiodirection of cyclization are explained.