79102-23-1Relevant articles and documents
Diastereoselective One-Pot Synthesis of Oxazolines Using Sulfur Ylides and Acyl Imines
Mehedi, Md Shafaat Al,Tepe, Jetze J.
, p. 7219 - 7226 (2019/06/14)
This work describes an extended version of the Corey-Chaykovsky reaction to access oxazolines using sulfur ylides and stable precursors of acyl imines. The reaction proceeds through a mixture of aziridines and oxazolines, which provides the trans-oxazolines following in situ Heine-type aziridine ring expansion upon treatment with BF3·OEt2. Following the same one-pot procedure, amidine imides react with the sulfur ylides to provide imidazolines.
Friedel-Crafts reactions of some N-acylaziridines: Oxazolines as intermediates
Mall,Buchholz,Stamm
, p. 377 - 380 (2007/10/02)
Without heat supply, AlCl3 and 3-substituted 1-acyl-2-phenylaziridines 1a,b, and 2b in benzene provided the respective Friedel-Crafts products 3a,b, and 4b (acylated 1-substituted 2,2-diphenylethylamines) which in part were further converted to 1,1,2,2-teraphenylethane (5). Oxazolines 6a,b, and 7b were also found. It is shown by means of 2,4,5-triphenyloxazoline 6b that oxazolines are intermediates for 3, 4, and 5. The uncommon heterolysis of these particular oxazolines is discussed.
Single Electron Transfer versus Nucleophilic Ring Opening in Reactions of Cis-Trans Pairs of Activated 2-Phenylaziridines. Strong Influence of Nitrogen Pyramid for N-Benzoylaziridines
Falkenstein, Reinhard,Mall, Thomas,Speth, Dieter,Stamm, Helmut
, p. 7377 - 7381 (2007/10/02)
Activated 2-phenylaziridines with a second substituent R in position 3 were made to react with xanthyl anion X(1-).Nucleophilic ring opening is the only reaction that occurs with sulfonyl activation.The analogous N-benzoylaziridines 1 undergo this type of ring opening when the two substituents Ph and R are trans.The cis isomers (cis-1, Ph and R cis) react in this manner to a negligible extent if any.The (nearly) exclusive ring cleavage reaction of cis-1 is C-N homolysis of an intermediate ketyl formed by single electron transfer (SET) from X(1-).This cis-trans phenomenon is in accordance with the hypothesis that the two competing reactions depend in an opposite manner on the steepness of the nitrogen pyramid.A predominant or exclusive final result of SET is reductive aziridine opening and dimerization of the xanthyl radical X(.).Formation of both diastereomers of the amidoethylated xanthene in one case (R = Me) is evidence for a cross combination of X(.) with the radical formed by homolytic ring opening.Cross combination is also a likely path for R = H (no cis-trans isomerism), in addition to reductive ring opening. cis-Aziridines with dimethylcarbamoyl on nitrogen do not react via SET since the ketyl is not stabilized and therefore difficult to generate.Carbonyl attack on both types of acylaziridines competes more or less successfully with the two ring cleavage reactions.
Ring Opening of Aziridines by Different Fluorinating Reagents: Three Synthetic Routes to α,β-Fluoro Amines with Different Stereochemical Pathways
Alvernhe, Gerald M.,Ennakoua, Christine M.,Lacombe, Sylvie M.,Laurent, Andre J.
, p. 4938 - 4948 (2007/10/02)
The syntheses of α,β-fluoro amines from the reaction of secondary aziridines with either Olah's reagent (HF, pyridine) or anhydrous hydrogen fluoride and of N-activated aziridines with partially neutralized Olah's reagent (NR3-nHF) are reported.The stereo
