Diaziridines characterization

It was not their reactivity but their chemical inertness that was the true surprise when diazirines were discovered in 1960. Thus they are in marked contrast to the known linear diazo compounds which are characterized by the multiplicity of their reactions. For example, cycloadditions were never observed with the diazirines. Especially surprising is the inertness of diazirines towards electrophiles. Strong oxidants used in their synthesis like dichromate, bromine, chlorine or hypochlorite are without action on diazirines. Diazirine formation may even proceed by oxidative dealkylation of a diaziridine nitrogen in (186) without destruction of the diazirine ring (75ZOR2221). The diazirine ring is inert towards ozone simple diazirines are decomposed only by more than 80% sulfuric acid (B-67MI50800). 

From l-cyclohexyl-3-ethyldiaziridine, crystalline derivatives have been prepared with p-toluenesulfonyl chloride and with 3,5-dinitro-benzoyl chloride, e.g., 46/ The quantitative liberation of iodine from acid iodide solution characterizes these compounds as true diaziridines. 

For the characterization of 1,3-dialkyl-diaziridines, derivatives can be prepared with phenyl isocyanate. The reaction products (47) are... 

Diaziridines 96a and 96b react with diethyl acetylenedicarboxylate to yield oily products, presumed to be 97a and 97b. These have been characterized by hydrolyzing them to the known pyrazolinones 98a and 98b, respectively [Eq. (17)]. A similar observation has been made in the reaction of l-methyl-3,3-pentamethylenediaziridine (96b) with ethyl propiolate. The reaction of 3,3-pentamethylenediaziridine with ethyl propiolate, on the other hand, yields a simple 1 1 Michael adduct. ... 

The end-product from synthesis of a diaziridine and its fission to alkylhydrazine is the same as is obtained by direct treatment of an amine with chloramine or hydroxylamine-O-sulfonic acid, as the carbonyl component of the Schiff base is recovered however, the detour through the diaziridine is worthwhile because in the direct reaction a considerable excess of the amine must be used to suppress further reaction of the alkylhydrazine product with the animating agent, whereas the diaziridines are unaffected thereby moreover, the diaziridine route is more widely applicable. Even further, the diaziridine route avoids both the requirement for an excess of alkali and the production of the hydrazine as a very dilute aqueous solution, both of which characterize the direct reaction. Indeed it provides an effective and generally applicable synthesis of mono-284,285 and 1,1-dialkyl-hydrazines.286... 

Sridar, C. Kobayashi, Y Brevig, H. Kent, U.M. Puppali, S.G. Rimoldi, J.M. Hollenberg, P.F. S3mthesis of substituted phenyl diaziridines and characterization as mechanism-based inactivators of human c3dochrome P450 2B6. Drug Metab. Dispos. 2006, 34, 1849. 

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