TY - JOUR
T1 - Electron Ionization Induced Fragmentation of some 3-Aroylamino-5-Methyl-1,2,4- Oxadiazoles and 3-Acetylamino-5-Aryl-1,2,4-Oxadiazoles
AU - Di Stefano, Vita
AU - Indelicato, Serena
AU - Ceraulo, Leopoldo
AU - Bongiorno, David
AU - Avellone, Giuseppe
AU - Frenna, Vincenzo
AU - Boga, Carla
AU - Zuppiroli, Luca
AU - Spinelli, Domenico
AU - Spinelli, Domenico
PY - 2017
Y1 - 2017
N2 - Background and Objectives: 1,2,4-Oxadiazoles show a high reactivity and represent starting compounds for the synthesis of several other heterocycles. Some their derivatives can give the so called Boulton-Katritzky Reactions (BKR) which opens the way to the synthesis of several azoles. For this reason we have registered the mass spectra of several 3-aroylamino-5-methyl-1,2,4-oxadiazoles and 3-acetylamino-5-aryl1,2,4-oxadiazoles.Methods and Results: Thus, studying the mass spectra of the isomeric couple 3-benzoylamino-5-methyl-1,2,4-oxadiazole (1A) and 3-acetylamino-5-phenyl-1,2,4-oxadiazoles (1B) we have observed that MIKE and CID MIKE spectra of their molecular ions and of the [M - CH2CO](+). evidence that several fragmentation processes arise from common structure(s).Conclusions: These findings lead to suggest that the BKR could occur also under electron ionization. In order to evidence possible substituent effects the EI-MS spectra of a large series of 3-aroylamino-5-methyl-1,2,4-oxadiazoles (2A-19A) and of the corresponding 3-acetylamino-5-aryl-1,2,4-oxadiazoles (2B-19B) have been examined.
AB - Background and Objectives: 1,2,4-Oxadiazoles show a high reactivity and represent starting compounds for the synthesis of several other heterocycles. Some their derivatives can give the so called Boulton-Katritzky Reactions (BKR) which opens the way to the synthesis of several azoles. For this reason we have registered the mass spectra of several 3-aroylamino-5-methyl-1,2,4-oxadiazoles and 3-acetylamino-5-aryl1,2,4-oxadiazoles.Methods and Results: Thus, studying the mass spectra of the isomeric couple 3-benzoylamino-5-methyl-1,2,4-oxadiazole (1A) and 3-acetylamino-5-phenyl-1,2,4-oxadiazoles (1B) we have observed that MIKE and CID MIKE spectra of their molecular ions and of the [M - CH2CO](+). evidence that several fragmentation processes arise from common structure(s).Conclusions: These findings lead to suggest that the BKR could occur also under electron ionization. In order to evidence possible substituent effects the EI-MS spectra of a large series of 3-aroylamino-5-methyl-1,2,4-oxadiazoles (2A-19A) and of the corresponding 3-acetylamino-5-aryl-1,2,4-oxadiazoles (2B-19B) have been examined.
KW - 2
KW - 4-oxadiazoles
KW - Mass spectrometry; Fragmentation mechanisms; EI induced rearrangements; boulton-Katritzky reactions (BKR); 3-acylamino-1
KW - 2
KW - 4-oxadiazoles
KW - Mass spectrometry; Fragmentation mechanisms; EI induced rearrangements; boulton-Katritzky reactions (BKR); 3-acylamino-1
UR - http://hdl.handle.net/10447/245882
M3 - Article
VL - 21
SP - 2207
EP - 2215
JO - Current Organic Chemistry
JF - Current Organic Chemistry
SN - 1385-2728
ER -