In this question, I need to find the order of decreasing rate of solvolysis of the above molecules with aqueous ethanol.
I think this can be done by finding the species that can form the most stable carbocation intermediate (and consequently, solvolysis will easily take place).
Now, the third molecule is obviously going to produce the least stable carbocation (since it can only form a secondary carbocation and no hydride shift is possible).
That leaves with us the first two molecules.
In the first molecule, the carbocation can be stablised by resonance. I believe that hyperconjugation from the methyl group will also help.
In the second structure, the carbocation formed will be tertiary and it too is relatively stable.
I had this notion that resonance in the first structure would make the carbocation formed by it the most stable. So, my answer was 1>2>3.
But it seems that I am wrong. The correct answer is 2>3>1 (ie. C).
Could someone tell me why this is the correct answer (and also clarify the mistakes in my assumptions)? Thank you for the help.