These oxygen-containing functional groups appear everywhere in synthesis and biology, but each behaves differently depending on whether the oxygen acts as a nucleophile, base, leaving-group partner, or ring-opening site.
Predict the acid-base behavior and hydrogen-bonding properties of alcohols, ethers, and epoxides.
Convert alcohols into better leaving groups and choose between substitution and elimination pathways.
Apply Williamson ether synthesis and understand its substrate limitations.
Predict regioselectivity in epoxide opening under basic versus acidic conditions.
Checkpoint Questions
Q: Why is tosylation useful before substitution of an alcohol?
A: It converts a poor leaving group (OH) into a very good leaving group (OTs) without changing the carbon-oxygen stereochemistry at the moment of activation.
Q: Where does methoxide attack an unsymmetrical epoxide under basic conditions?
A: At the less substituted carbon, because the mechanism is SN2-like.