Identify the correct reactivity order for the E 2 elimination reaction of the following compounds with alcoholic KOH : (i) (ii) (iii)

Step-by-step solution

The reactivity of alkyl halides towards E2 elimination with a strong base like alcoholic KOH depends primarily on the stability of the developing alkene character in the transition state. A more stable alkene product corresponds to a lower activation energy and a faster reaction rate. Compound (i), 1-chloro-1-phenylpropane, is a secondary alkyl halide. Elimination of HCl yields 1-phenylpropene. This is a disubstituted alkene that is highly stabilized by extended conjugation with the phenyl ring and hyperconjugation