Problems and exercisesAldol condensation: importance and mechanism
Exercise 1
Which products can form when a mixture of propanal and butanal is treated with aqueous NaOH? How would you selectively prepare the product in which butanal provides the enolate and propanal the carbonyl?
Exercise 2
Diacetone alcohol decomposes into acetone when heated with a base. Explain this fact and why, by contrast, the condensation of butanal with hot NaOH gives 2-ethylhex-2-enal in good yield.
Exercise 3
Propose a synthesis of (E)-4-phenylbut-3-en-2-one (benzylideneacetone) and explain why the reaction is clean even though it is carried out under equilibrium conditions.