Aziridines nitrogen unsubstituted

Aziridines with Nitrogen Unsubstituted 352.2 N-Alkyl-andN-AIkenyl-aziridines... 

Aziridines with Nitrogen Unsubstituted 3J2.2 N-Alkyl- and N-Alkenyl-aziridines... 

Other non-oxidative procedures have also been used to deaminate aziridines. For example, aziridines react with carbenes to yield ylides which subsequently decompose to the alkene. Dichlorocarbene and ethoxycarbonylcarbene have served as the divalent carbon source. The former gives dichioroisocyanides, e.g. (281), as by-products (72TL3827) and the latter yields imines (72TL4659). This procedure has also been applied to aziridines unsubstituted on the nitrogen atom although the decomposition step, in this case, is not totally stereospecific (72TL3827). 

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 use of isophthalic acid-2-methyl aziridine was also reported as a bonding agent for composite propellants in the literature. Based on this fact, its analog, that is, isophthalic dimethyl oxaziridine (reaction product of oxaziridine unsubstituted on the nitrogen and isophthaloyl dichloride) also appears to be a potential bonding agent [223] but needs to be evaluated in propellant formulations. 

Padwa and Hamilton examined other aziridines where the nitrogen was unsubstituted.43 44 cis-1,2-Diphenylaziridine (21) on refluxing with DMAD in benzene gave 85% of the adduct 22 DEAD was also used. tranj-2-Benzoyl-3-phenylaziridine (23) gave the pyrrole 24 with DMAD the latter was also synthesized from 4-benzyl-2-phenyl-5-oxazolone (26), via 25, which was oxidized with selenium dioxide to 24. 

Another synthetic method for the preparation of aziridinyl ketones involves the initial modification of unsaturated ketones, with formation of /3-methoxyamino derivatives, followed by treatment with either metal alcoholates [11, 28, 29, 30, 31], or hydroxylamine hydrochloride and then potassium hydroxide [32]. An obvious drawback of this approach is the possibility of obtaining an exclusively unsubstituted nitrogen atom for the aziridinyl ketones. Among the advantages are high yields for these reactions. For example, Jin et al. [31] recorded yields of aziridine 18 of 99%. In other publications the yields of target compounds were reported to be around 90%. 

Heterocycles form a specific class of monomers. They do not usually undergo radical polymerization, and the kind of ionic polymerization mechanism is determined by the kind of heteroatom, substituent and ring size. Oxiranes and, aziridines are polymerized by both ionic mechanisms. With the exception of lactone, four-membered and larger heterocycles with oxygen and with substituted nitrogen can only be polymerized cationically heterocycles with unsubstituted nitrogen can also be polymerized anionically. 

N-Unsubstituted aziridines can be elaborated by taking advantage of the nucleophilicity of the nitrogen center. One noteworthy example is the palladium-catalyzed arylation of aziridine 201 with /i-bromonitrobenzene 202 using a... 

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