Dimethylamine reacts with iodoethane by substitution to produce a mixture of products.
Which compound is not a possible product of this reaction?
[(CH3)2NH2]+I−[(\text{CH}_3)_2\text{NH}_2]^+\text{I}^-[(CH3)2NH2]+I−
CH3N(C2H5)2\text{CH}_3\text{N}(\text{C}_2\text{H}_5)_2CH3N(C2H5)2
(CH3)2NC2H5(\text{CH}_3)_2\text{NC}_2\text{H}_5(CH3)2NC2H5
[(CH3)2N(C2H5)2]+I−[(\text{CH}_3)_2\text{N}(\text{C}_2\text{H}_5)_2]^+\text{I}^-[(CH3)2N(C2H5)2]+I−