destroyer OC # 24 said that when in acid, it will attack the more substituted carbon. When in base, attack the least substituted carbon. This is very clear to me. However, in the McMurry page 651 said, when in acid, if only primary and secondary, it will attack the less substituted by SN2. but when tertary present, it attack to high substituted by SN1. what am i missing here? please.