Question

How do grignard reagents react with water?

Answer 1

Irreversibly. This [is sometimes exploited by chemists.](https://socratic.org/questions/why-does-the-glassware-have-to-be-dry-in-a-grignard-reaction)

Explanation:

The carbanionic nucleophile reacts with the electrophilic proton on the water molecule:

`R-MgX + H_2O rarr R-H + MgXOHdarr`

The reaction is irreversible, but it does have some synthetic utility if you want to label an hydorcarbyl chain with an isotope of hydrogen, `""^2H` or `""^3H`, simply by using heavy or tritiated water.