Formation of Azides by Addition Reactions

The formation of organic azides by the addition of a preformed azide moiety to unsaturated systems seemed until recently to be unpromising as a synthetic procedure and consequendy received scant attention. For example, simple alkenes were found to be inert towards hydrazoic acid in the conditions used by early workers , and additions to nitrile - and thione functions led to the 

although the reactions of quinones with hydrazoic acid (section IV.B.2) were established in 1915, similar additions to a range of a,/3-unsaturated carbonyl compounds were not demonstrated until 1951. Since then, comprehensive studies have shown that other 

In contrast with hydrogen halide additions, which have been well summarized in standard texts there are very few mechanistic 

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