A. Blackhall, D. L. Brydon, A. Sagar
1980
Citations
0
Influential Citations
7
Citations
Journal
Journal of The Chemical Society-perkin Transactions 1
Abstract
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 [i.e. the second stage of the nitration of (1)] also shows considerable variation of product ratio according to the conditions.