Consider the preparation of ethers via the acid-catalyzed intermolecular dehydration of alcohols. Wh — Alcohols Phenols and Ethers Chemistry Question
Question
Consider the preparation of ethers via the acid-catalyzed intermolecular dehydration of alcohols. Which of the following mechanistic statements are true?
💡 Solution & Explanation
Step 1 is protonation (fast). Step 2 is the $S_N2$ attack of a neutral alcohol on the oxonium ion (slow, rate-determining) to form the ether and release water. Secondary and tertiary alcohols suffer from severe steric hindrance, causing elimination ($E1$/$E2$) to dominate over substitution, forming alkenes (Statement D). Statement C is false; mixing two different alcohols yields a complex mixture of three different ethers, making it synthetically useless for unsymmetrical ethers.