# Why can't Grignard reagents react like Organolithium does (with acids)?

I'd read yesterday that Grignard reagents can't give ketones on reaction with carboxylic acids. It is because of the fact that Grignard reagent is a "super-base", and it will deprotonate the acid to form a carboxylate salt, rather than doing a $$\ce{Nu-}$$ attack.

However, after watching a video on Youtube, on the reaction of organolithium with acids (example reaction below),

I wondered,

• After the acid-base reaction, why couldn't Grignard reagent (when taken in excess) do a $$\ce{Nu-}$$ attack on the carboxylate salt, just like organolithium does and then form ketone? Just like it does with an ester, acid chloride, etc.
• Does this answer your question? Why are organolithium and organomagnesium compounds nucleophilic in nature? Aug 29 '20 at 7:44
• @Safdar, No. I couldn't think how a difference in Nu nature can prevent the grignard reagent from attacking the carboxylate salt? Aug 29 '20 at 7:53
• After formation of salt, the $\ce{O-}$ makes carbon way less electrophilic due to the distribution of electron density, so we need a much better nucleophile. Aug 29 '20 at 7:56