# What is the role of ammonium chloride in the workup of a Grignard reaction?

In the following Grignard reaction, why is aqueous ammonium chloride used to get to the products? I don't see how it participated in or modified the reaction from what is normally expected.

• This question has been edited to be more obviously on-topic. – A.K. Jan 18 at 23:50
• In scientific writing, brevity is highly valued. I do not see the point of padding a post when the question is perfectly clear and answerable. It is a waste of time for the editor as well as for future readers. To make myself abundantly clear, I am not criticising the edit, but rather the situation which necessitates this edit. – orthocresol Jan 18 at 23:55

Ammonium chloride ($$\ce{NH4Cl}$$) is the work-up reagent that quenches the magnesium alkoxide product of the Grignard addition. It is the reagent of choice as it is a proton source without being acidic; acidic conditions could result in protonation of the tertiary alcohol product and elimination to the alkene. It also ensures that all inorganic salts of Mg will extract into the aqueous phase.