File Download
 
Links for fulltext
(May Require Subscription)
 
Supplementary

Article: Water- and acid-mediated excited-state intramolecular proton transfer and decarboxylation reactions of ketoprofen in water-rich and acidic aqueous solutions
  • Basic View
  • Metadata View
  • XML View
TitleWater- and acid-mediated excited-state intramolecular proton transfer and decarboxylation reactions of ketoprofen in water-rich and acidic aqueous solutions
 
AuthorsLi, MD1
Yeung, CS1
Guan, X1
Ma, J1
Li, W1
Ma, C1
Phillips, DL1
 
Issue Date2011
 
PublisherWiley - V C H Verlag GmbH & Co KGaA. The Journal's web site is located at http://www.wiley-vch.de/home/chemistry
 
CitationChemistry - A European Journal, 2011, v. 17 n. 39, p. 10935-10950 [How to Cite?]
DOI: http://dx.doi.org/10.1002/chem.201003297
 
AbstractWe present an investigation of the decarboxylation reaction of ketoprofen (KP) induced by triplet excited-state intramolecular proton transfer in water-rich and acidic solutions. Nanosecond time-resolved resonance Raman spectroscopy results show that the decarboxylation reaction is facile in aqueous solutions with high water ratios (water/acetonitrile≥50 %) or acidic solutions with moderate and strong acid concentration. These experimental results are consistent with results from density functional theory calculations in which 1) the activation energy barriers for the triplet-state intramolecular proton transfer and associated decarboxylation process become lower when more water molecules (from one up to four molecules) are involved in the reaction system and 2) perchloric acid, sulfuric acid, and hydrochloric acid can shuttle a proton from the carboxyl to carbonyl group through an initial intramolecular proton transfer of the triplet excited state, which facilitates the cleavage of the C-C bond, thus leading to the decarboxylation reaction of triplet state KP. During the decarboxylation process, the water molecules and acid molecules may act as bridges to mediate intramolecular proton transfer for the triplet state KP when KP is irradiated by ultraviolet light in water-rich or acidic aqueous solutions and subsequently it generates a triplet-protonated carbanion biradical species. The faster generation of triplet-protonated carbanion biradical in acidic solutions than in water-rich solutions with a high water ratio is also supported by the lower activation energy barrier calculated for the acid-mediated reactions versus those of water-molecule-assisted reactions. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
 
ISSN0947-6539
2013 Impact Factor: 5.696
 
DOIhttp://dx.doi.org/10.1002/chem.201003297
 
ISI Accession Number IDWOS:000296262400020
 
ReferencesReferences in Scopus
 
DC FieldValue
dc.contributor.authorLi, MD
 
dc.contributor.authorYeung, CS
 
dc.contributor.authorGuan, X
 
dc.contributor.authorMa, J
 
dc.contributor.authorLi, W
 
dc.contributor.authorMa, C
 
dc.contributor.authorPhillips, DL
 
dc.date.accessioned2012-08-16T05:48:28Z
 
dc.date.available2012-08-16T05:48:28Z
 
dc.date.issued2011
 
dc.description.abstractWe present an investigation of the decarboxylation reaction of ketoprofen (KP) induced by triplet excited-state intramolecular proton transfer in water-rich and acidic solutions. Nanosecond time-resolved resonance Raman spectroscopy results show that the decarboxylation reaction is facile in aqueous solutions with high water ratios (water/acetonitrile≥50 %) or acidic solutions with moderate and strong acid concentration. These experimental results are consistent with results from density functional theory calculations in which 1) the activation energy barriers for the triplet-state intramolecular proton transfer and associated decarboxylation process become lower when more water molecules (from one up to four molecules) are involved in the reaction system and 2) perchloric acid, sulfuric acid, and hydrochloric acid can shuttle a proton from the carboxyl to carbonyl group through an initial intramolecular proton transfer of the triplet excited state, which facilitates the cleavage of the C-C bond, thus leading to the decarboxylation reaction of triplet state KP. During the decarboxylation process, the water molecules and acid molecules may act as bridges to mediate intramolecular proton transfer for the triplet state KP when KP is irradiated by ultraviolet light in water-rich or acidic aqueous solutions and subsequently it generates a triplet-protonated carbanion biradical species. The faster generation of triplet-protonated carbanion biradical in acidic solutions than in water-rich solutions with a high water ratio is also supported by the lower activation energy barrier calculated for the acid-mediated reactions versus those of water-molecule-assisted reactions. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
 
dc.description.naturelink_to_subscribed_fulltext
 
dc.identifier.citationChemistry - A European Journal, 2011, v. 17 n. 39, p. 10935-10950 [How to Cite?]
DOI: http://dx.doi.org/10.1002/chem.201003297
 
dc.identifier.doihttp://dx.doi.org/10.1002/chem.201003297
 
dc.identifier.eissn1521-3765
 
dc.identifier.epage10950
 
dc.identifier.hkuros203396
 
dc.identifier.isiWOS:000296262400020
 
dc.identifier.issn0947-6539
2013 Impact Factor: 5.696
 
dc.identifier.issue39
 
dc.identifier.pmid21850720
 
dc.identifier.scopuseid_2-s2.0-80052849918
 
dc.identifier.spage10935
 
dc.identifier.urihttp://hdl.handle.net/10722/159295
 
dc.identifier.volume17
 
dc.languageeng
 
dc.publisherWiley - V C H Verlag GmbH & Co KGaA. The Journal's web site is located at http://www.wiley-vch.de/home/chemistry
 
dc.publisher.placeGermany
 
dc.relation.ispartofChemistry - A European Journal
 
dc.relation.referencesReferences in Scopus
 
dc.subject.meshAcids - chemistry
 
dc.subject.meshAnti-Inflammatory Agents, Non-Steroidal - chemistry
 
dc.subject.meshDecarboxylation
 
dc.subject.meshKetoprofen - chemistry
 
dc.subject.meshProtons
 
dc.subject.meshSpectrum Analysis, Raman
 
dc.subject.meshWater - chemistry
 
dc.titleWater- and acid-mediated excited-state intramolecular proton transfer and decarboxylation reactions of ketoprofen in water-rich and acidic aqueous solutions
 
dc.typeArticle
 
<?xml encoding="utf-8" version="1.0"?>
<item><contributor.author>Li, MD</contributor.author>
<contributor.author>Yeung, CS</contributor.author>
<contributor.author>Guan, X</contributor.author>
<contributor.author>Ma, J</contributor.author>
<contributor.author>Li, W</contributor.author>
<contributor.author>Ma, C</contributor.author>
<contributor.author>Phillips, DL</contributor.author>
<date.accessioned>2012-08-16T05:48:28Z</date.accessioned>
<date.available>2012-08-16T05:48:28Z</date.available>
<date.issued>2011</date.issued>
<identifier.citation>Chemistry - A European Journal, 2011, v. 17 n. 39, p. 10935-10950</identifier.citation>
<identifier.issn>0947-6539</identifier.issn>
<identifier.uri>http://hdl.handle.net/10722/159295</identifier.uri>
<description.abstract>We present an investigation of the decarboxylation reaction of ketoprofen (KP) induced by triplet excited-state intramolecular proton transfer in water-rich and acidic solutions. Nanosecond time-resolved resonance Raman spectroscopy results show that the decarboxylation reaction is facile in aqueous solutions with high water ratios (water/acetonitrile&#8805;50 %) or acidic solutions with moderate and strong acid concentration. These experimental results are consistent with results from density functional theory calculations in which 1) the activation energy barriers for the triplet-state intramolecular proton transfer and associated decarboxylation process become lower when more water molecules (from one up to four molecules) are involved in the reaction system and 2) perchloric acid, sulfuric acid, and hydrochloric acid can shuttle a proton from the carboxyl to carbonyl group through an initial intramolecular proton transfer of the triplet excited state, which facilitates the cleavage of the C-C bond, thus leading to the decarboxylation reaction of triplet state KP. During the decarboxylation process, the water molecules and acid molecules may act as bridges to mediate intramolecular proton transfer for the triplet state KP when KP is irradiated by ultraviolet light in water-rich or acidic aqueous solutions and subsequently it generates a triplet-protonated carbanion biradical species. The faster generation of triplet-protonated carbanion biradical in acidic solutions than in water-rich solutions with a high water ratio is also supported by the lower activation energy barrier calculated for the acid-mediated reactions versus those of water-molecule-assisted reactions. &#169; 2011 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim.</description.abstract>
<language>eng</language>
<publisher>Wiley - V C H Verlag GmbH &amp; Co KGaA. The Journal&apos;s web site is located at http://www.wiley-vch.de/home/chemistry</publisher>
<relation.ispartof>Chemistry - A European Journal</relation.ispartof>
<subject.mesh>Acids - chemistry</subject.mesh>
<subject.mesh>Anti-Inflammatory Agents, Non-Steroidal - chemistry</subject.mesh>
<subject.mesh>Decarboxylation</subject.mesh>
<subject.mesh>Ketoprofen - chemistry</subject.mesh>
<subject.mesh>Protons</subject.mesh>
<subject.mesh>Spectrum Analysis, Raman</subject.mesh>
<subject.mesh>Water - chemistry</subject.mesh>
<title>Water- and acid-mediated excited-state intramolecular proton transfer and decarboxylation reactions of ketoprofen in water-rich and acidic aqueous solutions</title>
<type>Article</type>
<description.nature>link_to_subscribed_fulltext</description.nature>
<identifier.doi>10.1002/chem.201003297</identifier.doi>
<identifier.pmid>21850720</identifier.pmid>
<identifier.scopus>eid_2-s2.0-80052849918</identifier.scopus>
<identifier.hkuros>203396</identifier.hkuros>
<relation.references>http://www.scopus.com/mlt/select.url?eid=2-s2.0-80052849918&amp;selection=ref&amp;src=s&amp;origin=recordpage</relation.references>
<identifier.volume>17</identifier.volume>
<identifier.issue>39</identifier.issue>
<identifier.spage>10935</identifier.spage>
<identifier.epage>10950</identifier.epage>
<identifier.eissn>1521-3765</identifier.eissn>
<identifier.isi>WOS:000296262400020</identifier.isi>
<publisher.place>Germany</publisher.place>
</item>
Author Affiliations
  1. The University of Hong Kong