SUBSTITUENT EFFECTS ON THE ELECTRON TRANSFER-INITIATED PHOTOCHEMICAL TRANSFORMATION OF 1,2,4-TRIAZOLE-SUBSTITUTED α-DEHYDROARYLALANINAMIDES INTO 2(1H)-QUINOLINONE DERIVATIVES

摘要

An investigation was undertaken to elucidate substituent effects on the photoreactivity of 1,2,4-triazole-substituted α-dehydroarylalaninamides [(Z)-1] as well as on the selectivity of 2(1H)-quinolinone derivatives (2) from a synthetic point of view. It was found that photoinduced electron transfer-initiated cyclization of (2)-1 bearing a meta-substituted phenyl or a 4-substituted naphthalen-1-yl group in methanol proceeds with a moderate to good efficiency affording the corresponding product 2 in a selectivity ranging from 33 to 100%.