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

Step-by-step solution

The given reaction is an E 2 elimination, which proceeds via a concerted, single-step mechanism. In the rate-determining step of an E 2 reaction, the base abstracts a -hydrogen (or its isotope) simultaneously with the departure of the leaving group. Thus, the breaking of the - C - H (or C - D , C - T ) bond is involved in the rate-determining step. The bond dissociation energy of carbon-isotope bonds follows the order: C - T > C - D > C - H . Because the C - H bond is the weakest among them, it is broken most easil