Luminescence Properties of 2-[2-Allyl(arenesulfonyl)oxyphenyl]- 5-(2,6-difluorophenyl)-1,3,4-oxadiazoles

Abstract

The alkylation of 2-(2,6-difluorophenyl)-5-(2-hydroxyphenyl)-1,3,4-oxadiazole with allyl bromide gave 2-(2-allyloxyphenyl)-5-(2,6-difluorophenyl)-1,3,4-oxadiazole, and sulfonylation of the same substrate with benzene- and p-toluenesulfonyl chlorides afforded the corresponding 2-(2-arenesulfonyloxyphenyl)-5-(2,6-difluorophenyl)-1,3,4-oxadiazoles. 2-(2-Allyloxyphenyl)- and 2-(2-tosyloxyphenyl)-5-(2,6-difluorophenyl)- 1,3,4-oxadiazoles showed strong luminescence in the ultraviolet region (λ_max^fl 335–374 nm, φ = 0.12–0.80), whereas the luminescence quantum yield of 2-(2-benzenesulfonyloxyphenyl)-5-(2,6-difluorophenyl)- 1,3,4-oxadiazole was considerably lower (λ_max^fl 334–338 nm, φ = 0.012–0.090).