Grignard and alcohol

[JustwantDDS]

Advertisement - Members don't see this ad

whats the product here?

 

[PooyaH]

Diethyl ether.

 

[JustwantDDS]

ch3ch2MgCl will attack....which C?

the answer says ethane
i thought that was off

 

[PooyaH]

ch3ch2MgCl will attack....which C?

the answer says ethane
i thought that was off

You would only get an ethane if there was an acidic proton in which Gringard could react with.

 

[JustwantDDS]

so, can you explain the mechanism a bit for this one?
thanks

 

[needzmoar]

whats the product here?

It's an acid base reaction, essentially. You get CH3CH2MgCl as an intermediate that reacts with the acidic proton reagent #2

 

[PooyaH]

so, can you explain the mechanism a bit for this one?
thanks

I'm confused myself right now lol. You'd have CH3CH2MgCl first which will act as a nucleophile, then I believe it would attack the the ethanol, forming this:

CH3CH3 + CH3CH2O-MgCl+

 

[wired202808]

I'm confused myself right now lol. You'd have CH3CH2MgCl first which will act as a nucleophile, then I believe it would attack the the ethanol, forming this:

CH3CH3 + CH3CH2O-MgCl+

why isnt the answer Ch3CH(OH)Ch2Ch3?

 

[PooyaH]

why isnt the answer Ch3CH(OH)Ch2Ch3?

Gringard always reacts with the most acidic proton first. Here, CH3CH2MgCl will attack the acidic proton of the alcohol.

 

[wired202808]

Gringard always reacts with the most acidic proton first. Here, CH3CH2MgCl will attack the acidic proton of the alcohol.

smart! so basically its taking off the H from the alcohol so thats gonna get you that diethyl ether right?

its the little things that seem to get me!

 

[PooyaH]

smart! so basically its taking off the H from the alcohol so thats gonna get you that diethyl ether right?

its the little things that seem to get me!

Nope, this is why you shouldn't do reactions in your head all the time. I made the same mistake at first. But it should give you an ethane as I showed the mechanism in my earlier post.

 

[wired202808]

Nope, this is why you shouldn't do reactions in your head all the time. I made the same mistake at first. But it should give you an ethane as I showed the mechanism in my earlier post.

so whats the final answer?

 

[PooyaH]

so whats the final answer?

You'd get an ethane as I said in my earlier post! lol

CH3CH3 + CH3CH2OMgCl

 

[wired202808]

You'd get an ethane as I said in my earlier post! lol

CH3CH3 + CH3CH2OMgCl

got it! hope the real dat doesnt have anything this funky!

 

[JustwantDDS]

heres the reaction!!!
basically if there a protic solvent, ethanol, it makes an alkane..........

 

[DrRoyal Pains]

.

 

[DrRoyal Pains]

I thought it was diethyl ether as well.

 

[needzmoar]

I thought it was diethyl ether as well.

How would that mechanism look like? The grignard is an extremely basic molecule. I think the grignard lab really reinforced the fact that it is a strongly basic. Anyways, acid/base reactions are almost always rapid and exothermic. Even if there was another functional group on the substrate, say a carbonyl, the grignard will deprotonate the alcohol first.