Question

The compound that gives precipitate on warming with aqueous AgNO3 (i.e. undergoes fastest SN1 solvolysis) is:

• A. I
• B. II
• C. III
• D. IV

Hint:

Work out what carbocation each C-Br bond gives on ionization and pick the most stable one.

Answer 1

The Correct Option is C

Method: rank cation types. Aryl cation (I) very high energy. Electron-poor heteroaryl cation (IV) even worse. Allylic cation (II) moderately stabilized. Tropylium cation (III), aromatic, is far more stable than all others.

\[\boxed{\text{III}}\]