Diaziridine formation

Diazirines (3) smoothly add Grignard compounds to the N—N double bond, giving 1-alkyldiaziridines. Reported yields are between 60 and 95% without optimization (B-67MI50800). The reaction is easily carried out on a preparative scale without isolation of the hazardous diazirines and may serve as an easy access to alkylhydrazines. The reaction was also used routinely to detect diazirines in mixtures. The diaziridines formed are easily detected by their reaction with iodide. Phenyllithium or ethylzinc iodide also add to (3) with diaziridine formation. 

Habisch " investigated the action of chloramine on simple Schiff s bases. In the aliphatic series, diaziridine formation was observed in all the cases investigated. Ethereal solutions of chloramine react with Schiff s bases at room temperature within a few hours [Eq. (32)]. Table VI gives details of a few of the 1-alkyl-diaziridines prepared. 

A final statement on the mechanism of the diaziridine formation cannot yet be made. The obvious formulation [Eq. (36) ] as a reaction of the CN double bond with the imen 39 (with an electron sextet) is almost certainly excluded. The formation of 39 as an intermediate has been jiroposed for the Raschig hydrazine synthesis, but has been disjmted. The following facts are against a diaziridine formation corresjionding to Eq. (36) ... 

In contrast to the Raschig hydrazine synthesis, diaziridine formation occurs in solvents of low polarity such as ether and in the absence of strong bases. An ionization of chloramine and the formation of 39 is thus unlikely. 

The rate of the diaziridine formation shows that the chloramine is attacked by the Schiff s base. Although ethereal chloramine solutions are only decomposed after weeks of standing, in the presence of a Schiffs base the chloramine is consumed after a few hours. The Schiff s base therefore does not enter into the reaction merely after the decomposition of the chloramine as it would have to do if formula 39 was an intermediate. Probably the chloramine adds onto the Schiff s base [Eq. (37) ] and ring closure of the geminal addition ]>roduct occurs. ... 

Diaziridines, formation in reactions of carbenes with azo compounds 87UK1324. 

Smooth diaziridine formation even in the presence of additional functional groups in the starting ketone, allowed many individual diaziridines to be made for pharmacological testing. More than fifty compounds of types 92 and 93 with the basic piperidone and tropine structures, were synthesized. ... 

In the steroids diaziridine formation occurs most successfully in the sterically unhindered 3-position, less favorably in the 2-position, in which formation of an aminal-like intermediate is hindered by 1,3-diaxial interaction with a methyl group. In the sterically most hindered 17-position, diaziridine synthesis may be effected by formation of a Schiff base with cyclohexylamine, thus eliminating water before introduction of the aminating... 

The diaziridine formation mentioned above to occur with HN3" was observed when the perfluorinated thioketone 101 was treated with HN3... 

Work on diazirine synthesis during the last 10 years has not led to fundamentally new ways either of diaziridine formation or of diaziridine dehydrogenation, in spite of the remarkable volume of synthetic activity, for example, in the search for biologically active diazirines. 

The diaziridine formation mentioned above to occur with HN... 

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