Ritter
Hazard to Others
Posts: 370
Registered: 20-6-2008
Location: Earth
Member Is Offline
Mood: Curious
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Solvent-free organic synthesis with microwaves
I haven't read the full article nor could I open the 2K graphics attachment in the abstract (it was blank), but microwave chemistry under solvent-free
conditions appears to offer some significant advantages to the amateur chemist given the ready availability of used & portable microwave ovens.
Quote: | Tetrahedron
Volume 58, Issue 11, 11 March 2002, Pages 2155-2162
Abstract
doi:10.1016/S0040-4020(02)00085-6
Copyright © 2002 Elsevier Science Ltd. All rights reserved.
Solvent-free preparation of amides from acids and primary amines under microwave irradiation
Laurence Perreuxa, André Loupy, and François Volatronb
a Laboratoire des Réactions Sélectives sur Supports, Université Paris-Sud, CNRS, ICMO, UMR 8615, Bâtiment 410, 91405, Orsay Cedex, France b
Laboratoire de Chimie Physique, Université Paris-Sud, 91405, Orsay Cedex, France
Received 26 July 2001; revised 19 October 2001; accepted 27 December 2001. ; Available online 1 February 2002.
Abstract
Synthesis of amides via pyrolysis of the salts obtained by mixing neat primary amines and carboxylic acids were realized under solvent-free conditions
within short times and appreciable yields under microwave activation. The evident specific non-thermal microwave effects are attributed to polarity
increase during the course of the reaction, due to development of a dipole in the transition state.
Synthesis of amides via pyrolysis of corresponding salts obtained by mixing neat primary amines and carboxylic acids were realized under solvent-free
conditions within short times and appreciable yields under microwave activation. Specific non-thermal microwave effects are evidenced and attributed
to enhancements in microwave–materials interaction due to polarity increase (formation of a polar transition state) during the course of the
reaction.
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I'm curious about the reaction mechanism involved as they appear to claim that only primary amines undergo this reaction. Alkyl, aryl & alkyl
primary amines undergo this reaction.
This appears to be related to the Nylon-6,6 industrial synthesis that pyrolyzes the adipic acid salt of 1,6-heamethylenediamine.
Since this reaction only eliminates a molecule of water, I'm curious about whether salts of secondary amines could be made to work.
[Edited on 13-8-2008 by Ritter]
[Edited on 14-8-2008 by Ritter]
Ritter
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\"The production of too many useful things results in too many useless people.\"
Karl Marx
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solo
International Hazard
Posts: 3972
Registered: 9-12-2002
Location: Estados Unidos de La Republica Mexicana
Member Is Offline
Mood: ....getting old and drowning in a sea of knowledge
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Quote: | Originally posted by Ritter
I haven't read the full article nor could I open the 2K graphics attachment in the abstract (it was blank), but microwave chemistry under solvent-free
conditions appears to offer some significant advantages to the amateur chemist given the ready availability of used & portable microwave ovens.
Quote: | Tetrahedron
Volume 58, Issue 11, 11 March 2002, Pages 2155-2162
Abstract
doi:10.1016/S0040-4020(02)00085-6
Copyright © 2002 Elsevier Science Ltd. All rights reserved.
Solvent-free preparation of amides from acids and primary amines under microwave irradiation
Laurence Perreuxa, André Loupy, and François Volatronb
a Laboratoire des Réactions Sélectives sur Supports, Université Paris-Sud, CNRS, ICMO, UMR 8615, Bâtiment 410, 91405, Orsay Cedex, France b
Laboratoire de Chimie Physique, Université Paris-Sud, 91405, Orsay Cedex, France
Received 26 July 2001; revised 19 October 2001; accepted 27 December 2001. ; Available online 1 February 2002.
Abstract
Synthesis of amides via pyrolysis of the salts obtained by mixing neat primary amines and carboxylic acids were realized under solvent-free conditions
within short times and appreciable yields under microwave activation. The evident specific non-thermal microwave effects are attributed to polarity
increase during the course of the reaction, due to development of a dipole in the transition state.
Synthesis of amides via pyrolysis of corresponding salts obtained by mixing neat primary amines and carboxylic acids were realized under solvent-free
conditions within short times and appreciable yields under microwave activation. Specific non-thermal microwave effects are evidenced and attributed
to enhancements in microwave–materials interaction due to polarity increase (formation of a polar transition state) during the course of the
reaction.
|
I'm curious about the reaction mechanism involved as they appear to claim that only primary amines undergo this reaction. Alkyl, aryl & alkyl
primary amines undergo this reaction.
This appears to be related to the Nylon-6,6 industrial synthesis that pyrolyzes the adipic acid salt of 1,6-heamethylenediamine.
Since this reaction only eliminates a molecule of water, I'm curious about whether salts of secondary amines could be made to work.
[Edited on 13-8-2008 by Ritter]
[Edited on 14-8-2008 by Ritter] |
..........read and see the whole thing ....Loupy also has a book all dealing with microwave chemistry...I have it if you want it just say so......solo
Attachment: Solvent-free preparation of amides from acids and primary amines under microwave irradiation .pdf (144kB) This file has been downloaded 2364 times
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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