949-02-0Relevant academic research and scientific papers
Synthesis of 3,5-disubstituted-1,2,4-oxadiazoles using tetrabutylammonium fluoride as a mild and efficient catalyst
Gangloff, Anthony R.,Litvak, Joane,Shelton, Emma J.,Sperandio, David,Wang, Vivian R.,Rice, Kenneth D.
, p. 1441 - 1443 (2007/10/03)
Tetrabutylammonium fluoride (TBAF) was found to be a mild and efficient catalyst for the synthesis of 3,5-disubstituted-1,2,4-oxadiazoles. Using 0.1 - 1.0 equivalents of TBAF in THF for 1 - 24 h at room temperature, alkanoyl- and aroyloxyamidines were converted in high yield to the corresponding 3,5-disubstituted-1,2,4-oxadiazoles. A variety of R and R′ substituents were investigated.
Formation and Thermal Reaction of O-(N-Acetylbenzimidoyl)benzamidoxime: Comparison with the Formation of 3,5-Disubstituted 1,2,4-Oxadiazoles from O-Acetylarylamidoximes and O-Aroylacetamidoximes
Ooi, Ngan Sim,Wilson, David A.
, p. 1792 - 1799 (2007/10/02)
Salts of O-(benzimidoyl)benzamidoxime have been obtained by the action of N-chloro- or N-bromo-succinimide, or the halogens, on benzamidoxime.Acetylation of the free base gave the title compound, which underwent a thermal cyclisation, with loss of acetamide, to give 3,5-diphenyl-1,2,4-oxadiazole.The mechanism of the reaction, in diphenyl ether, closely paralleled the thermal cyclisation of O-acetylarylamidoximes and O-aroylacetamidoximes, and is thought to involve a polar cyclisation step followed by rate-determining proton transfer. 13C N.m.r. spectra for 32 oxime, amidoxime, O-acetylamidoxime, 5-methyl-1,2,4-oxadiazol-3-yl, and 3-methyl-1,2,4-oxadiazol-5-yl groups on the phenyl ring are calculated.
