Addition of Nitrenes and Nitrenoids to Alkenes

Notwithstanding the drawbacks to the method, the addition of nitrenes to alkenes is a well studied classical method for direct aziridination. The original reactions (often involving alkoxycarbonylnitrenes) employed harsh conditions, resulting in nonstereoselective transformations. In these pioneering reports, the requi- 

This unusually high stereoselectivity is due to the high barrier to N-inversion and the presence of the electron-withdrawing phthalimido group. It can be demonstrated that the reaction is under kinetic control when the reaction mixtures described above are allowed to warm to temperatures near or above 0 °C, whereupon a partial or complete inversion of configuration at nitrogen can be seen (by NMR spectroscopy). 

It has since transpired that the active aziridinating species in these reactions are the N-acetoxylated hydrazine derivatives, rather than nitrenes exposure of ethyl-quinazolinone ( Q1-NH2 ) to lead tetraacetate at low temperature generates N-(acetoxyamino)-quinazolinone ( Q -NHOAc ), which is a relatively stable sub- 

Che et al. have reported the use of iodobenzene diacetate as an alternative to lead tetraacetate in the original Rees-Atkinson reactions of a relatively narrow range of olefin substrates (primarily styrenes) [11]. 

Since the mid-1990s, synthetic attention has been directed more towards the use of metal-stabilized nitrenes as synthetic effectors of alkene aziridination. In 1969 it was reported that Cu(i) salts were capable of mediating alkene aziridination when treated with tosyl azide, but the method was limited in scope and was not adopted as a general method for the synthesis of aziridines [12]. Metaloporphyrins [13] were shown to be catalysts for the aziridination of alkenes in the presence of the nitrene precursor N-tosyliminophenyliodinane [14] in the early 1980s, but the reaction did 

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