Transformation of trans-4-aryl-3-chloro-1-(2-chloroethyl)azetidin-2-ones into 3-aryl-2-(ethylamino)propan-1-ols via intermediate 1-(1-aryl-2-chloro-3-hydroxypropyl)aziridines and trans-2-aryl-3-(hydroxymethyl)aziridines.
trans-4-Aryl-3-chloro-1-(2-chloroethyl)azetidin-2-ones, prepared through cyclocondensation of chloroketene and the appropriate imines in a diastereoselective way, were unexpectedly transformed into 3-aryl-2-(ethylamino)propan-1-ols using LiAlH(4) in THF under reflux. A stepwise analysis showed that the initially formed 1-(1-aryl-2-chloro-3-hydroxypropyl)aziridines were converted into trans-2-aryl-3-(hydroxymethyl)aziridines, most probably via N-spiro bis-aziridinium intermediates, which were subsequently prone to undergo ring opening by LiAlH(4) to afford 3-aryl-2-(ethylamino)propan-1-ols.
Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000 Ghent, Belgium.
Karen
K
Mollet
Matthias
M
D'hooghe
Norbert
N
De Kimpe
D001384:Azetidines / Q000138:chemical synthesis* / Q000737:chemistry*; D001388:Aziridines / Q000138:chemical synthesis* / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D013141:Spiro Compounds / Q000737:chemistry; D013237:Stereoisomerism
D001384:Azetidines; D001388:Aziridines; D007097:Imines; D013141:Spiro Compounds