Look for posts by Ritter. He has thoroughly covered the addition of hydrogen halides (HF, HCl, HBr, HI) to terminal alkenes (C-C=C) to form halo-alkanes (C-C[F,Cl, Br,I]-C) which can then be reacted through substitution via ammonolysis (NH3) or aminolysis (NH2CH3, for example) to aquire the desired final amine (C-C[NH2, NHCH3]-C).
Elimination has been reported to occur when iodo-alkanes (C-C-C) are reacted with ammonia (NH3) or amines (NH2CH3), thus forming the starting terminal alkene (C-C=C) and the ammonia/amine hydrohalogenide salt (NH4I, NH3CH3I) as products.
Sorry, but I could illustrate the ionic structures for you very well using ASCII.