# Acetophenone reacted with LDA and diethyl carbonate. Why do I need HCl?

I'm working on a practice problem that asks for the product of acetophenone and LDA reacted with diethyl carbonate. After this, it says step 2 is HCl. After I react the first step, I get the correct answer to the problem - ethyl benzoylacetate. I'm asking why the problem says that HCl is added even when everything is neutral in the product I got and it's correct.

For isolation and purification, you want to get rid of that negative charge (initially introduced by the strongest base you added: LDA). This is called quenching and typically performed with weak acids. I personally would use ammonium chloride for this type of reaction, but carefully adding dilute $\ce{HCl}$ will do the trick just as well. You should use $\ce{HCl}$’s proton to remove any remaining negative charges and eliminate $\ce{LiCl}$.
• @5antoro I wouldn’t call them minor. 1) They are stoichiometric; 2) not too safe on the $\mathrm{p}K_\mathrm{a}$ values, but I could well assume ethyl benzoylacetate to be equally or more acidic than ethanol. – Jan Nov 19 '16 at 20:57