71088-63-6Relevant academic research and scientific papers
Rapid Boulton–Katritzky rearrangement of 5-aryl-3-[2-(piperidin-1-yl)ethyl]-1,2,4-oxadiazoles upon exposure to water and HCl
Kayukova, Lyudmila A.,Uzakova, Asem B.,Vologzhanina, Anna V.,Akatan, Kydyrmolla,Shaymardan, Esbol,Kabdrakhmanova, Sana K.
, p. 643 - 649 (2018/08/17)
[Figure not available: see fulltext.] Сhemical stability of 3-(2-aminoethyl)-5-substituted 1,2,4-oxadiazoles was studied with respect to Boulton–Katritzky rearrangement, which is known to produce planar pyrazolines and pyrazoles upon heating in DMF at 150°C or without solvent at 240°C. The reactivity of 5-aryl-3-[2-(piperidin-1-yl)ethyl]-1,2,4-oxadiazoles in one type of Boulton–Katritzky rearrangement was observed at room temperature in H2O, DMF + H2O, and in the presence of HCl. Hydrolysis of 3,5-disubstituted 1,2,4-oxadiazoles under the first two conditions gave 2-amino-1,5-diazaspiro[4.5]dec-1-en-5-ium benzoates, while the action of HCl on 3,5-disubstituted 1,2,4-oxadiazoles produced their hydrochlorides along with 2-amino-1,5-diazaspiro[4.5]dec-1-en-5-ium chloride hydrate. Thus, the reaction afforded spiropyrazoline compounds instead of products with a planar structure.
Cyclization of O-benzoyl-β-piperidinopropionamidoximes to form 5-phenyl-3-(β-piperidino)ethyl-1,2,4-oxadiazoles
Kayukova,Zhumadildaeva,Praliyev
, p. 2100 - 2105 (2007/10/03)
The reactions of β-piperidinopropionamidoxime with substituted benzoyl chlorides afforded O-benzoylation products, which underwent cyclization to form 5-phenyl-3-(β-piperidino)ethyl-1,2,4-oxadiazoles upon heating in dimethylformamide in the presence of molecular sieves at 60°C for 1 - 2.5 h. Heating of O-benzoyl-β-piperidinopropionamidoxime in dimethylformamide in the presence of K2CO3 at 85°C for 4 h afforded a mixture of 5-phenyl-3-(β-piperidino)ethyl-1,2,4-oxadiazole, benzoic acid, and N-(β-piperidino)ethylurea.
