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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: shalikadm on June 11, 2012, 10:56:38 AM

Title: Do esters react with amines ?
Post by: shalikadm on June 11, 2012, 10:56:38 AM
Esters react with concentrate NH3 when heated..Does it happens with amines also ?
Title: Re: Do esters react with amines ?
Post by: discodermolide on June 11, 2012, 10:59:12 AM
Esters react with concentrate NH3 when heated..Does it happens with amines also ?


Yes.
I have done it by heating in a sealed tube using catalytic KCN. One can also use a Parr apparatus. Yields vary depending on the amine.
Title: Re: Do esters react with amines ?
Post by: Babcock_Hall on June 11, 2012, 11:00:42 AM
Are you interested only in esters derived from methanol, or do you have other alcohols in mind?
Title: Re: Do esters react with amines ?
Post by: shalikadm on June 11, 2012, 11:03:30 AM
Esters react with concentrate NH3 when heated..Does it happens with amines also ?


Yes.
I have done it by heating in a sealed tube using catalytic KCN. One can also use a Parr apparatus. Yields vary depending on the amine.

Do we have to use a catalytic for that..?
Can't we use a concentrated amine(primary or secondary) and just heat the solution..?
Title: Re: Do esters react with amines ?
Post by: shalikadm on June 11, 2012, 11:06:17 AM
Are you interested only in esters derived from methanol, or do you have other alcohols in mind?
not only from methanol...any ester..
Title: Re: Do esters react with amines ?
Post by: discodermolide on June 11, 2012, 11:07:34 AM
Esters react with concentrate NH3 when heated..Does it happens with amines also ?


Yes.
I have done it by heating in a sealed tube using catalytic KCN. One can also use a Parr apparatus. Yields vary depending on the amine.

Do we have to use a catalytic for that..?
Can't we use a concentrated amine(primary or secondary) and just heat the solution..?

Goes better with a catalyst, primary amines are, of course, more reactive than secondary, but if you push it you can get them to react as well.
Title: Re: Do esters react with amines ?
Post by: Babcock_Hall on June 11, 2012, 03:46:01 PM
So called "active esters" form amides with amines.  The first alcohol (to the best of my knowledge) was 4-nitrophenol, and the paper was in JACS in 1959 (Bodzanski might have been the corresponding author, but my memory is uncertain).  Pentafluorophenol is another alcohol that forms active esters.  The pKa of the conjugate acid of the leaving group is lower for an active ester than for a typical ester.
Title: Re: Do esters react with amines ?
Post by: orgopete on June 11, 2012, 06:37:13 PM
Formate esters and malonate esters are also more reactive to amines.