Aziridines reaction with nitrous acid

Aziridines not substituted on the nitrogen atom react with nitrous acid to produce olefins.324 An N-nitroso compound is an intermediate (2-51) other reagents that produce such intermediates also give olefins. The reaction is stereospecific cis aziridines give cis olefins and trans aziridines give trans olefins.325 Aziridines carrying N-alkyl substituents can be converted to olefins by treatment with ferrous iodide326 or with m-chloroperbenzoic acid.327 An N-oxide intermediate (9-28) is presumably involved in the latter case. 

Aziridines not substituted on the nitrogen atom react with nitrous acid to produce alkenes. ° An A-nitroso compound is an intermediate (12-50) other reagents that produce such intermediates also give alkenes. The reaction is stereospecific cis... 

The base-catalysed addition of acetone to trans-aziridines (368) affords oxazolidines (369). The complex reaction of 2-aminoethanol with nitrous acid results in the nitroso-compound (370). °... 

Azetidines are thermally stable and less reactive than aziridines. They behave in their reactions almost like secondary alkylamines. The value of azetidine is 11.29 and so it is more basic than aziridine (pAT = 7.98) and even dimethylamine ( Ka = 10.73). Azetidines unsubstituted on the N-atom react with alkyl halides to give 1-alkylazetidines which can react further to give quaternary azetidinium salts. With acyl halides, they produce acylazetidines and with nitrous acid, they give 1-nitrosoazetidines. 

The action of nitrous acid on the benzodiazepine A -oxide 38 gives the nitrosoamino derivative 39,234 which reacts with alcohols, ethanethiol and various amino compounds, such as hydrazines and guanidine, by replacement of the methyl(nitroso)amino group.235 Reaction with aziridine affords the aziridinyl compound 40f or the 2-(aziridin-l-yl)ethylainino derivative 40g, depending on the conditions. 

As a result of our previous work on the scope and mechanism of tertiary amine nitrosation (X), we became interested in the behavior of N-alkylaziridines toward nitrous acid. Possible modes of reaction are illustrated in Scheme 1. The operation of either path A or C would be consistent with our previous studies of oxidative dealkylation of tertiary amines (1 ), while pathway B would be akin to the observed cheleotropic transformation of N-nitroso-aziridines (2). 

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