Iodine azide, IN 3 , adds to alkenes by an electrophilic mechanism similar to that of bromine.

Question:

Iodine azide, IN₃, adds to alkenes by an electrophilic mechanism similar to that of bromine. If a mono-substituted alkene such as 1-butene is used, only one product results:

(a) Add lone-pair electrons to the structure shown for IN₃, and draw a second resonance form for the molecule.

(b) Calculate formal charges for the atoms in both resonance structures you drew for IN₃ in part (a).

(c) In light of the result observed when IN3 adds to 1-butene, what is the polarity of the 1?N₃ bond? Propose a mechanism for the reaction using curved arrows to show the electron flow in each step.