Hi.
I know that grignard systems (organomagnesium halides stabilized in ether solvents) are very sensitive to the following things:
water
alcohols
carbonyl groups
imines
nitriles
halides
acids
But what I'm curious about is, are they sensitive toward alkalai metals and also are they sensitive toward bases, such as specifically sodium hydroxide?
Would a molecule RMgX react in some way with a species of MOH where M = alkalai? Would it react with metallic M? M is not lithium. Lithium is excluded from this entire post (unless you have something to add) because lithium has its own series of organometallic compounds, that I'm not interested in here.
Basically, the reason I am interested is because Grignard systems are sensitive toward water, and one application for such a system, unfortunately involves insitu generation of water, and it must be removed chemically. Kinetic drying agents are not satisfactory. The water must be destroyed immediately.
One such method would be to use an acid anhydride such as acetic anhydride, formic acetic acid. This is obviously 100% out of the question, becuse the grignard reagent will react with acetic anhydride, and the produced acid will also destroy the reagent. This is not satisfactory.
Another avenue is to use the opposite: an alkoxide. But this produces an alcohol, which, like the former, will destroy the grignard reagent and produce a useless alkane. This is also out of the question.
But I wonder about using sodium oxide, Na
2O, as a water scavenger, as it would form 2NaOH as a product. Would this work, or will either entity, the oxide, or the hydroxide, interfere with the grignard adduct?
And also what of alkalai metals like Na metal? They will react with water to form the hydroxide as before, and evolve hydrogen gas. Are the free metals reactive toward the reagents?
I have never seen any examples before of these types of compounds being detrimental to such a system, but I have also never seen their employment, so I truly am in the dark.
Can anyone suggest a chemical reaction that involves combination with or destruction of water, but does not yield an acidic or basic compound, but rather a neutral one or perhaps something that reacts with water and becomes insoluble in a system, allowing for removal?
I know of no such methods, and I hope to get some ideas.
As for just how much water is needed to be removed, it is thought to be equimolar to the molar of the grignard reagent.
PrimoPyro
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