Draw the structure of the acetal that forms when benzaldehyde is heated with 1,2-ethanediol in an acid medium. Write a detailed mechanism that justifies your formation. Describe step by step the hydrolysis of this acetal in an aqueous acid medium.

SOLUTION:



Acetal formation mechanism:



The hydrolysis of the acetal in an aqueous acid medium follows the steps inverse to those of the synthesis.



Cyclic acetal hydrolysis mechanism.