W. Shi, X. Qian, G. Song
Dec 1, 2000
Citations
0
Influential Citations
28
Citations
Journal
Journal of Fluorine Chemistry
Abstract
Abstract Two 2-fluorophenyl-5-substitued cyclopropyl-1,3,4-oxadiazoles ( IIIa–b ) with cis / trans isomers were synthesized from the corresponding hydrazide ( Ia ) and aroyl chlorides by two-step reactions. Six asymmetrical 2-(2,4-dichloro-5-fluorophenyl)-5-aryl-1,3,4-oxadiazoles ( IIIc–h ) were obtained by one step reaction of 2,4-dichloro-5-fluorobenzoic acid hydrazide ( Ic ) with the corresponding aromatic carboxylic acid in the presence of phosphorus oxychloride under reflux. However, the similar reaction of 4-fluorophenoxyacetic acid hydrazide ( Ib ) with 2,4-dichloro-5-fluorobenzoic acid failed to yield the desired asymmetrical 2-(2,4-dichloro-5-fluorophenyl)-5-(fluorophenoxymethyl)-1,3,4-oxadiazole, and the resulting product was characterized as symmetrical 2,5-bis(2,4-dichloro-5-fluorophenyl)-1,3,4-oxadiazole (DCFPO). A possible reaction mechanism is suggested. Insecticidal activities of these nine new compounds against armyworms ( Pseudaletia separata Walker ) were determined.