Question

From the list of structures on the right, select the major product formed when the following alkyl bromide:

Answer 1

This is a very hindered tertiary alkyl halide, so SN2 reactions aren't really possible.

That leaves E2 reactions. Potential E2 reaction products are C and E, since the carbon bearing the bromine must be part of the double bond.

Of these, C is the most stable (it has more alkyl groups on the double bond), but E is favored kinetically, since deprotonating a -CH3 group is much easier than deprotonating a -CH group.

For a small, unhindered base (methoxide), the major product is indeed the more stable one, so for 1, the major product is C.

For a larger, branched base (t-butoxide), the major product is formed by deprotonation of the most accessible proton, so for @, the answer is E.