Iodine azide reactions with allenes

The addition of iodine azide to double bonds gives p-iodo azides. The reagent can be prepared in situ from KI—NaNa in the presence of Oxone -wet alumina. The addition is stereospecific and anti, suggesting that the mechanism involves a cyclic iodonium ion intermediate. The reaction has been performed on many double-bond compounds, including allenes and a,p-unsaturated ketones. Similar reactions can be performed with BrNa and CfNa. 1,4-Addition has been found with acyclic conjugated dienes. In the case of BrNa, both electrophilic and free-radical mechanisms are important, whUe with CIN3 the addi-... 

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