Grignard question

[Jongho Yoon]

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When methyl Grignard reacts with acetic acid, for example,

would it remove the most acidic proton, which is proton attached to O
(acting as a base), resulting in CH3COO-MgBr

or

would it act as a nucleophile, attacking the acid to result in acetone?

I believe it produces acetone, but I don't know when grignard acts as a base, taking the most acidic proton off, or when it acts as a nucleophile, attacking the carbonyl carbon via Sn2

 

[BaylorDDS]

Grignard will rip acidic protons off. So for above you get ch3coo- (minus on o)

 

[miedvied]

The methyl in methyl grignard is an absurdly strong base, muuuch stronger a base than it is a nucleophile. I definitely second the previous answer: it's going to grab that acidic proton.

 

[Jongho Yoon]

What if methyl grignard is reacting with acetic chloride?

I know grignard react as a nucleophile in this case resulting in acetone.

In this case,

Why is it not acting as a base, removing acidic alpha proton on acetic chloride?

 

[PooyaH]

What if methyl grignard is reacting with acetic chloride?

I know grignard react as a nucleophile in this case resulting in acetone.

In this case,

Why is it not acting as a base, removing acidic alpha proton on acetic chloride?

The alpha hydrogen is not very acidic!

 

[BaylorDDS]

Hydrogens are acidic enough for grignard to rip them off when they are connected to an electronegative element (like O or N)