5509-89-7Relevant articles and documents
Substitution Reactions of Phenylated Aza-heterocycles. Part 1. Nitration of 2,5-Diphenyl-1,3,4-oxadiazole: a Product Study using High Performance Liquid Chromatography
Blackhall, Alexander,Brydon, Donald L.,Saga, Anthony J. G.,Smith, David M.
, p. 773 - 777 (2007/10/02)
Contrary to a previous literature report, nitration of 2,5-diphenyl-1,3,4-oxadiazole (1) under various conditions gives a mixture of all six possible 2,5-bisnitrophenyl derivatives, which may be analysed quantitatively using high performance liquid chromatography.Nitration using nitric acid alone gives mainly the three isomers with p-nitrophenyl groups, i.e. (7), (9), and (10), whereas mixed acids and nitronium tetrafluoroborate give mainly meta-nitration products, i.e. (6), (8), and (9).Nitration of the three 2-(nitrophenyl)-5-phenyl-1,3,4-oxadiazoles also shows considerable variation of product ratio according to the conditions.