Synthesis and spectral properties of 3-(2-aryl-5-methyl-1,3-oxazol- 4-yl)-2-(2,5-dimethylthiophen-3-yl)cyclopent-2-en-1-ones

Alkylation of ethyl 4-(2,5-dimethylthiophen-3-yl)-3-oxobutanoate with 2-aryl-4-bromoacetyl-5-methyl-1,3-oxazole followed by decar-boxylation–cyclization of the intermediate diketo ester affords the title photochromic compounds. Relationship between the fluorescent characteristics, thermal stability of photoinduced form as well as quantum yields of photochemical reactions and the structure of these compounds was evaluated.