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: 3967
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)
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It's better to die on your feet, than live on your knees....Emiliano Zapata.
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