The acid strength of active methylene group in :
(i) `CH_(3)COCH_(2)COOC_(2)H_(5)`
(ii) `CH_(3)COCH_(2)COCH_(3)`
(iii) `C_(2)H_(5)OOCCH_(2)COOC_(2)H_(5)` decreases as :

Options

A. (i) `gt` iii `gt` ii
B. I `gt` (ii) `gt` iii
C. iii `gt` I `gt` ii.
D. `iiigtigtii`.

Answer

C

Explanation

In (ii) , `-CH_(2)-` group is attached to two electron withdrawing groups . Therefre it is most acidic.Acetate group `(CH_(3)COO^(-))` is less electron withdrawing than aceiyl group `(CH_(3)CO^(-))`.