Identify the correct order of acidic strength for the following compounds: (i) (ii) (iii)

Step-by-step solution

Boronic acids act as Lewis acids by accepting an OH^- ion from water to form a tetrahedral boronate anion, ArB(OH)₃^- . The acidic strength increases with the stability of this anion. Electron-withdrawing groups stabilize the anion and increase acidity, while electron-donating groups destabilize it and decrease acidity. The ethoxy group ( -OEt ) exhibits an electron-withdrawing inductive effect ( -I ) and an electron-donating resonance effect ( +R ). In the meta-isomer (ii), the -OEt group is at the meta position w