Identify the correct order of acidic strength for the indicated protons in the following compound:

Step-by-step solution

The acidic strength of a proton is directly proportional to the stability of its conjugate base. Removal of proton (ii) yields the cyclopentadienyl anion. This anion has 6 electrons in a cyclic, continuous conjugated system, making it aromatic and exceptionally stable. Removal of proton (i) yields the cycloheptatrienyl anion. This anion has 8 electrons in a cyclic, continuous conjugated system, making it antiaromatic and highly unstable. Removal of proton (iii) yields a localized tertiary carbanion on the alkyl cha