title: A facile synthesis of novel pyrrolizidines under classical and ultrasonic conditions.
abstract: Novel pyrrolizidines (1) were synthesized from 1,3-dipolar cycloaddition of azomethine ylides and dipolarophiles (4). The reactions were highly diastereoselective and regioselective and were carried out under reflux and ultrasonic condition at room temperature. In general, milder conditions and moderate improvements in rates and reaction times were observed when ultrasonic condition was used. The products were obtained in high yields, and their structures were determined by (1)H and (13)C NMR spectral data and X-ray diffraction.
authors.affiliation: Chemistry Department, Faculty of Science, Shahid Beheshti University, Evin, 1983963113, Tehran, Iran. k-jadidi@sbu.ac.ir
authors.forename: Khosrow
authors.initials: K
authors.lastname: Jadidi
authors.forename: Ramin
authors.initials: R
authors.lastname: Gharemanzadeh
authors.forename: Morteza
authors.initials: M
authors.lastname: Mehrdad
authors.forename: Hossein Reza
authors.initials: HR
authors.lastname: Darabi
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Khavasi
authors.forename: Davoud
authors.initials: D
authors.lastname: Asgari
mesh_terms: D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D018360:Crystallography, X-Ray; D003500:Cyclization; D007202:Indicators and Reagents; D013058:Mass Spectrometry; D008958:Models, Molecular; D008968:Molecular Conformation; D011763:Pyrrolizidine Alkaloids / Q000138:chemical synthesis* / Q000528:radiation effects; D014465:Ultrasonics
chemical_list: D007202:Indicators and Reagents; D011763:Pyrrolizidine Alkaloids