Aziridines from epoxides

Formation of Aziridines from Epoxides Amino-de-alkoxylation... 

Synthesis of aziridines from epoxides via amino alcohols or azido alcohols and reaction with phosphines or phosphites (see 1 edition). 

Aziridines from epoxides. A direct acc of epoxides with iminotriphenylphosphoranes yields are variable (< 5-84%). 

Oxaziridines unsubstituted at nitrogen as well as some iV-acylated oxaziridines offer synthetic potentialities due to their ability to transfer their nitrogen function to nucleophiles (Section 5.08.3.1.4). The simplicity of preparation of some aziridines from alkenes and the Spiro oxaziridine (S2) equals the simplicity of epoxidation. Aziridine (299), for example, is obtained by simple heating of indene with (52) in toluene (74KGS1629). 

The present authors have found that the preparation of 7V-acetyl aziridine derivates provides the most secure method of differentiating aziridines from primary amines which are alternate reaction products in a number of cases. The infrared spectra of the former derivatives show only a peak at 1690 cm" for a tertiary amide peaks at ca. 3440 and 1530 cm" indicative of a secondary amide are absent. Acetylation also shifts the aziridine ring protons to a lower field in the NMR by ca. 1 ppm relative to the parent aziridine. The A"-acetyl aziridines are hydrolyzed with 3% methanolic potassium hydroxide. " Published NMR spectra of several 16j5,17j -aziridines reveal resonance patterns resembling those of the respective epoxides. " ... 

Asymmetric Synthesis of Epoxides and Aziridines from Aldehydes and I mines... 

This review summarizes the best asymmetric methods for preparing epoxides and aziridines from aldehydes (or ketones) and imines. 

Of course, the key limitation of the ylide-mediated methods discussed so far is the use of stoichiometric amounts of the chiral reagent. Building on their success with catalytic asymmetric ylide-mediated epoxidation (see Section 1.2.1.2), Aggarwal and co-workers have reported an aza version that provides a highly efficient catalytic asymmetric synthesis of trans-aziridines from imines and diazo compounds or the corresponding tosylhydrazone salts (Scheme 1.43) [68-70]. 

Aziridines from Amino Epoxides by a Modified Payne... 

Research efforts are ongoing into the use of dinitrogen pentoxide for the industrial synthesis of nitrated hydroxy-terminated polybutadiene (NHTPB) from epoxidated HTPB (Section 3.10). The reaction of aziridines with dinitrogen pentoxide is an important route to 1,2-nitramine-niU ates and these reactions are discussed in Section 5.8.1. ... 

P8 Thermal conrotatory 4tt ring opening of aziridines and epoxides is a well-recognized method of generating azomethine and carbonyl ylidesd (From Johnson, 2003)... 

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