Iodine azide aziridine synthesis

Iodine azide, on the other hand, forms pure adducts with A -, A - and A -steroids by a mechanism analogous to that proposed for iodine isocyanate additions. Reduction of such adducts can lead to aziridines. However, most reducing agents effect elimination of the elements of iodine azide from the /mwj -diaxial adducts of the A - and A -olefins rather than reduction of the azide function to the iodo amine. Thus, this sequence appears to be of little value for the synthesis of A-, B- or C-ring aziridines. It is worthy to note that based on experience with nonsteroidal systems the application of electrophilic reducing agents such as diborane or lithium aluminum hydride-aluminum chloride may yet prove effective for the desired reduction. Lithium aluminum hydride accomplishes aziridine formation from the A -adducts, Le., 16 -azido-17a-iodoandrostanes (97) in a one-step reaction. The scope of this addition has been considerably enhanced by the recent... 

Reaction of iodine azide with olefins followed by reduction leads to a stereospecific synthesis of aziridines [59]. 

The alkene pseudohalogen adducts (15) of Scheme 8 are also useful intermediates for aziridine synthesis. These adducts are discussed later in Sections 3.S.6.2-4. The iodine azide and bromine azide adducts may be reduced to aziridines with many reagents recent references report use of lidiium aluminum hydride - and dimethylamineborane. The iodine isocyanate aziridination continues to prove useful, as in Scheme Since the recent reviews, - the mechanism of the triphenylphosphine-based... 

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