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Reduction of nitrile to amine

My textbook says you can "add LiAlH4 then dilute acid, or add Na and ethanol then reflux". Do you need to reflux the LiAlH4 one too or just the Na one?
Reply 1
Original post by SophieDizzy
My textbook says you can "add LiAlH4 then dilute acid, or add Na and ethanol then reflux". Do you need to reflux the LiAlH4 one too or just the Na one?

Hello,
Refluxing is kind if further oxidation, so it really depends on what type of amine whether primary, secondary or tertiary amines you want to get.
By Refluxing you will get primary amine.
I think so you have mistaken Na for Ni-Nickel. It should be refluxed with Nickel only
Original post by cpocha1
Hello,
Refluxing is kind if further oxidation, so it really depends on what type of amine whether primary, secondary or tertiary amines you want to get.
By Refluxing you will get primary amine.
I think so you have mistaken Na for Ni-Nickel. It should be refluxed with Nickel only


I thinl you may be confusing a few reactions.

The conversion of nitrile to amine is a reduction, so reflux is not further oxidation in this instance.
Reflux is a way of providing significant energy to a reaction, without boiling away the reagents. This drives reactions towards completion. When oxidising primary alcohols you will get further oxidation, because that is 'completion' of that reaction, but the reflux is just promoting completion ib general.

I don't believe there is a mechanism when using LiAlH4 to reduce nitriles that would continue to secondary or tertiary amines.
I think you may be confusing this with another way of making amines: nucleophilic substitution of haloalkanes with ammonia.



To answer the original question: no, the two reagent choices are separate ways of reducing the nitrile.
Reply 3
Original post by TutorsChemistry
I thinl you may be confusing a few reactions.

The conversion of nitrile to amine is a reduction, so reflux is not further oxidation in this instance.
Reflux is a way of providing significant energy to a reaction, without boiling away the reagents. This drives reactions towards completion. When oxidising primary alcohols you will get further oxidation, because that is 'completion' of that reaction, but the reflux is just promoting completion ib general.

I don't believe there is a mechanism when using LiAlH4 to reduce nitriles that would continue to secondary or tertiary amines.
I think you may be confusing this with another way of making amines: nucleophilic substitution of haloalkanes with ammonia.



To answer the original question: no, the two reagent choices are separate ways of reducing the nitrile.


I'm really sorry for that. And thanks that you have come forward and helped.
Reply 4
Thank you so much!!

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