The carboxylic acids having electron with drawing group, EWG (-I effect) at `alpha`-position undergoes decarboxylation more readily.
(a) `IIgt I (as CH_(2)CH(Cl)COOH` has-Cl atom at `alpha`-position).
(b) `I gt II (as-CH_(3)CO` group is at `alpha`-position)
(c) `I gtII` (as three-Cl atoms at `alpha`-position increases-I effect)
(d) `Igt II` (as structure I has `-NO_(2)` group at `alpha`-position).
