Microwave-Assisted Esterification of N-Acetyl-L-Phenylalanine Using Modified Mukaiyama’s Reagents: A New Approach Involving Ionic Liquids

2.50
Hdl Handle:
http://hdl.handle.net/11286/581395
Title:
Microwave-Assisted Esterification of N-Acetyl-L-Phenylalanine Using Modified Mukaiyama’s Reagents: A New Approach Involving Ionic Liquids
Authors:
Zhao, Hua; Song, Zhiyan; Cowins, Janet V.; Olubajo, Olarongbe
Abstract:
Inspired by the concept of ionic liquids (ILs), this study modified the original Mukaiyama’s reagent, 2-chloro-1-methylpyridinium iodide (m.p. 200-dec), from ionic solid into liquids by changing its anion. The esterification of N-acetyl-L-phenylalanine was investigated as a model reaction. The microwave irradiation was more effective in esterifying N-acetyl-L-phenylalanine than the conventional reflux method. The original Mukaiyama’s reagent was modified into ILs through manipulating its anion. However, only non-nucleophilic anions (such as EtSO4- and Tf2N-) were favorable since nucleophilic ones (such as CF3COO- and CH3COO-) could exchange with chlorine resulting in non-reactive coupling reagents. Two modified Mukaiyama’s compounds (i.e. hydrophilic [2- ClMePy][EtSO4] and hydrophobic [2-ClMePy][Tf2N]) have been identified as the best ILtype coupling reagents. The esterification reaction was greatly enhanced by using 1- methylimidazole as the base instead of conventional toxic tertiary amines, and by using excess amount of alcohols as solvents instead of dichloromethane. Overall, the method reported is effective and ‘greener’.
Affiliation:
Savannah State University
Citation:
Zhao, H., Song, Z., Cowins, J. V., & Olubajo, O. (2008). Microwave-Assisted Esterification of N-Acetyl-L-Phenylalanine Using Modified Mukaiyama’s Reagents: A New Approach Involving Ionic Liquids. International Journal of Molecular Sciences, 9(1), 33–44. MDPI AG. Retrieved from http://dx.doi.org/10.3390/ijms9010033
Publisher:
MDPI
Journal:
International Journal of Molecular Sciences
Issue Date:
16-Jan-2008
URI:
http://hdl.handle.net/11286/581395
DOI:
10.3390/ijms9010033
Additional Links:
http://www.mdpi.com/1422-0067/9/1/33
Type:
Article
Language:
en_US
ISSN:
1422-0067
Appears in Collections:
Faculty Research Articles

Full metadata record

DC FieldValue Language
dc.contributor.authorZhao, Huaen
dc.contributor.authorSong, Zhiyanen
dc.contributor.authorCowins, Janet V.en
dc.contributor.authorOlubajo, Olarongbeen
dc.date.accessioned2015-10-28T20:11:10Zen
dc.date.available2015-10-28T20:11:10Zen
dc.date.issued2008-01-16en
dc.identifier.citationZhao, H., Song, Z., Cowins, J. V., & Olubajo, O. (2008). Microwave-Assisted Esterification of N-Acetyl-L-Phenylalanine Using Modified Mukaiyama’s Reagents: A New Approach Involving Ionic Liquids. International Journal of Molecular Sciences, 9(1), 33–44. MDPI AG. Retrieved from http://dx.doi.org/10.3390/ijms9010033en
dc.identifier.issn1422-0067en
dc.identifier.doi10.3390/ijms9010033en
dc.identifier.urihttp://hdl.handle.net/11286/581395en
dc.description.abstractInspired by the concept of ionic liquids (ILs), this study modified the original Mukaiyama’s reagent, 2-chloro-1-methylpyridinium iodide (m.p. 200-dec), from ionic solid into liquids by changing its anion. The esterification of N-acetyl-L-phenylalanine was investigated as a model reaction. The microwave irradiation was more effective in esterifying N-acetyl-L-phenylalanine than the conventional reflux method. The original Mukaiyama’s reagent was modified into ILs through manipulating its anion. However, only non-nucleophilic anions (such as EtSO4- and Tf2N-) were favorable since nucleophilic ones (such as CF3COO- and CH3COO-) could exchange with chlorine resulting in non-reactive coupling reagents. Two modified Mukaiyama’s compounds (i.e. hydrophilic [2- ClMePy][EtSO4] and hydrophobic [2-ClMePy][Tf2N]) have been identified as the best ILtype coupling reagents. The esterification reaction was greatly enhanced by using 1- methylimidazole as the base instead of conventional toxic tertiary amines, and by using excess amount of alcohols as solvents instead of dichloromethane. Overall, the method reported is effective and ‘greener’.en
dc.language.isoen_USen
dc.publisherMDPIen
dc.relation.urlhttp://www.mdpi.com/1422-0067/9/1/33en
dc.subjectSavannah State University (Savannah, Ga.)en
dc.subjectAmino aciden
dc.subjectIonic liquiden
dc.subjectMukaiyama’s reagenten
dc.subjectMicrowaveen
dc.subjectEsterificationen
dc.titleMicrowave-Assisted Esterification of N-Acetyl-L-Phenylalanine Using Modified Mukaiyama’s Reagents: A New Approach Involving Ionic Liquidsen_US
dc.typeArticleen
dc.contributor.departmentSavannah State Universityen
dc.identifier.journalInternational Journal of Molecular Sciencesen
All Items in Savannah State University Repository are protected by copyright, with all rights reserved, unless otherwise indicated.