Novel photochemical rearrangement of 2,4,4,6-tetraphenylpyridin-3(4H)-one to an oxazole derivative

Abstract

Irradiation of 2,4,4,6-tetraphenylpyridin-3(4H)-one 1 in solution and in the solid state gave 1,3,6,6-tetraphenyl-2-azabicyclo[3.1.0]hex-2-en-4-one 4 as a primary photoproduct, which underwent a novel photorearrangement to yield 5-(2,2-diphenylethenyl)-2,4-diphenyloxazole 3 along with 3-hydroxy-2,4,5,6-tetraphenylpyridine 2: the structures of 3 and 4 were determined by X-ray structure analysis.