314030-41-6Relevant academic research and scientific papers
Synthesis of new benzocoumaryl oxadiazolyls as strong blue-green fluorescent brighteners
Rajesha,Kiran Kumar,Bhojya Naik,Mahadevan
, p. 88 - 94 (2012/06/18)
The benzocoumarin-3-ethylcarboxylate 2 on treatment with hydrazine hydrate at room temperature afforded benzocoumarin-3-carbohydrazide 3. The compound 3 served as key intermediate in the synthesis of the title compounds. Thus, benzocoumarin-1,3,4-oxadiazolyls 6a-e were obtained in two ways, i.e. one by direct cyclization of benzocoumarin-3-carbohydrazide 3 with substituted benzoic acids in POCl3 and the other by cyclization of Schiff bases of compounds 5a-e in the presence of bromine/acetic acid. The structures of the novel benzocoumaryl oxadiazolyls 6a-e were confirmed by spectral analysis. The benzocoumarin-1,3,4- oxadiazolyls 6a-e exhibited strong blue and green fluorescent properties. The Stoke's shifts range from 43 to 165 nm. The absorption and fluorescence maxima of the benzocoumaryl oxadiazolyls showed good bathochromic shifts.
