含窒素芳香族化合物の光環化付加反応による複素環合成

Abstract

Photochemistry of aromatic compounds has received much attention from both the mechanistic and synthetic perspectives, and the intra- and intermolecular photochemical cycloaddition of carbon aromatics is well documented. Furthermore, the photocycloaddition of alkenes to benzene derivatives is also a useful method for synthesizing natural products. However, in contrast, the photocycloaddition reaction of aza-aromatics, such as pyridines, pyridazines, pyrazines, or pyrimidines, is an underdeveloped area of research. We found that the induction of suitable substituents to appropriate position of aza-aromatic ring made the photoreactivity considerably high. Many new photochemical reactions for pyridine derivatives have been found in photodimerization, photocycloaddition with alkenes, furan, benzofuran or cyanonaphthalene. These reactions provide not only new photochemical aspect of aza-aromatics, but also useful synthetic method of polycyclic heterocycles.