Synthesis of 3-Pyridinols. II. Reaction of 4-Methyloxzaole with Dienophiles

Abstract

Condensation of I with several dienophiles caused three types of reaction, i.e. reaction A, B, and C; reaction B and C afforded 3-pyridinol derivatives. A likely mechanism of these reactions are considered as Diels-Alder's condensation of I with dienophiles and subsequent aromatization to pyridine nuclei.