Polycondensation of activated L‐valine and L‐leucine esters with various lewis acids
Identifieur interne : 003213 ( Istex/Corpus ); précédent : 003212; suivant : 003214Polycondensation of activated L‐valine and L‐leucine esters with various lewis acids
Auteurs : Tadamasa Nemoto ; Daisuke Ando ; Kensuke Naka ; Yoshiki ChujoSource :
- Journal of Polymer Science Part A: Polymer Chemistry [ 0887-624X ] ; 2007-02-01.
English descriptors
- KwdEn :
- Amino, Amino acid esters, Amino acids, Carbonyl, Carbonyl oxygen, Cation, Chem, Condensation reaction, Condensation reactions, Elution volume, Ester, Ftir, Ftir spectra, Hindrance, Isobutyl group, Isopropyl, Isopropyl group, Lewis acid, Lewis acids, Metal cation, Molecular weight, Naka, Nemoto, Peptide bonds, Polycondensation, Polym, Polym chem, Polymer, Polymer chemistry, Polymer science, Polymerization, Reaction mixture, Results show, Room temperature, Steric, Steric hindrance, Various kinds, Various metal, Wiley periodicals, Yttrium.
- Teeft :
- Amino, Amino acid esters, Amino acids, Carbonyl, Carbonyl oxygen, Cation, Chem, Condensation reaction, Condensation reactions, Elution volume, Ester, Ftir, Ftir spectra, Hindrance, Isobutyl group, Isopropyl, Isopropyl group, Lewis acid, Lewis acids, Metal cation, Molecular weight, Naka, Nemoto, Peptide bonds, Polycondensation, Polym, Polym chem, Polymer, Polymer chemistry, Polymer science, Polymerization, Reaction mixture, Results show, Room temperature, Steric, Steric hindrance, Various kinds, Various metal, Wiley periodicals, Yttrium.
Abstract
To develop a novel polycondensation method for the preparation of poly (amino acid)s, we screened a transition metal or a rare‐earth triflate as a Lewis acid for the polycondensation of activated amino acid esters in N,N‐dimethylformamide solutions at room temperature. The polymerizations of 4‐nitrophenyl L‐leucinate (1a) and 4‐nitrophenyl L‐valinate (1b) scarcely proceeded without any Lewis acid at room temperature. In the presence of 5 mol % metal triflates, especially scandium(III) trifluoromethanesulfonate, the polymerizations of both monomers were promoted effectively. The products, which were collected by the reaction mixture being poured into water, were recognized as poly(L‐valine)s by Fourier transform infrared spectroscopy, gel permeation chromatography analysis, and 1H NMR spectroscopy. These results showed that a metal triflate as a Lewis acid could coordinate to a carbonyl oxygen of activated L‐valinate and L‐leucinate even in a highly polar solvent, such as N,N‐dimethylformamide; therefore, the polymerizations of activated L‐valinate and L‐leucinate were promoted. Because steric hindrance derived from the isobutyl group in 1b was less than that of the isopropyl unit in 1a, the effect of the metals was not as sensitive for the polymerization of 1b. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 543–547, 2007
Url:
DOI: 10.1002/pola.21895
Links to Exploration step
ISTEX:E2930119DC315E12AB45BE12F8F61EE06D16445BLe document en format XML
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The polymerizations of 4‐nitrophenyl L‐leucinate (1a) and 4‐nitrophenyl L‐valinate (1b) scarcely proceeded without any Lewis acid at room temperature. In the presence of 5 mol % metal triflates, especially scandium(III) trifluoromethanesulfonate, the polymerizations of both monomers were promoted effectively. The products, which were collected by the reaction mixture being poured into water, were recognized as poly(L‐valine)s by Fourier transform infrared spectroscopy, gel permeation chromatography analysis, and 1H NMR spectroscopy. These results showed that a metal triflate as a Lewis acid could coordinate to a carbonyl oxygen of activated L‐valinate and L‐leucinate even in a highly polar solvent, such as N,N‐dimethylformamide; therefore, the polymerizations of activated L‐valinate and L‐leucinate were promoted. Because steric hindrance derived from the isobutyl group in 1b was less than that of the isopropyl unit in 1a, the effect of the metals was not as sensitive for the polymerization of 1b. © 2006 Wiley Periodicals, Inc. 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In the presence of 5 mol % metal triflates, especially scandium(III) trifluoromethanesulfonate, the polymerizations of both monomers were promoted effectively.</abstract><qualityIndicators><score>4.357</score><pdfVersion>1.3</pdfVersion><pdfPageSize>630 x 810 pts</pdfPageSize><refBibsNative>true</refBibsNative><abstractCharCount>1361</abstractCharCount><pdfWordCount>1969</pdfWordCount><pdfCharCount>12309</pdfCharCount><pdfPageCount>5</pdfPageCount><abstractWordCount>199</abstractWordCount></qualityIndicators><title>Polycondensation of activated L‐valine and L‐leucine esters with various lewis acids</title><genre><json:string>article</json:string></genre><host><title>Journal of Polymer Science Part A: Polymer 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acids</title></titleStmt><publicationStmt><authority>ISTEX</authority><publisher>Wiley Subscription Services, Inc., A Wiley Company</publisher><pubPlace>Hoboken</pubPlace><availability><licence>Copyright © 2006 Wiley Periodicals, Inc.</licence></availability><date type="published" when="2007-02-01"></date></publicationStmt><notesStmt><note type="content-type" subtype="article" source="article" scheme="https://content-type.data.istex.fr/ark:/67375/XTP-6N5SZHKN-D">article</note><note type="publication-type" subtype="journal" scheme="https://publication-type.data.istex.fr/ark:/67375/JMC-0GLKJH51-B">journal</note></notesStmt><sourceDesc><biblStruct type="article"><analytic><title level="a" type="main" xml:lang="en">Polycondensation of activated <hi rend="smallCaps">L</hi>‐valine and <hi rend="smallCaps">L</hi>‐leucine esters with various lewis acids</title><title level="a" type="short" xml:lang="en">Polycondensation with Various Lewis Acids</title><author xml:id="author-0000"><persName><forename type="first">Tadamasa</forename><surname>Nemoto</surname></persName><affiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan<address><country key="JP"></country></address></affiliation></author><author xml:id="author-0001"><persName><forename type="first">Daisuke</forename><surname>Ando</surname></persName><affiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan<address><country key="JP"></country></address></affiliation></author><author xml:id="author-0002" role="corresp"><persName><forename type="first">Kensuke</forename><surname>Naka</surname></persName><email>ken@chujo.synchem.kyoto‐u.ac.jp</email><affiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan<address><country key="JP"></country></address></affiliation><affiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan</affiliation></author><author xml:id="author-0003"><persName><forename type="first">Yoshiki</forename><surname>Chujo</surname></persName><affiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan<address><country key="JP"></country></address></affiliation></author><idno type="istex">E2930119DC315E12AB45BE12F8F61EE06D16445B</idno><idno type="ark">ark:/67375/WNG-T5K5V41X-H</idno><idno type="DOI">10.1002/pola.21895</idno><idno type="unit">POLA21895</idno><idno type="toTypesetVersion">file:POLA.POLA21895.pdf</idno></analytic><monogr><title level="j" type="main">Journal of Polymer Science Part A: Polymer Chemistry</title><title level="j" type="alt">JOURNAL OF POLYMER SCIENCE PART A: POLYMER CHEMISTRY</title><idno type="pISSN">0887-624X</idno><idno type="eISSN">1099-0518</idno><idno type="book-DOI">10.1002/(ISSN)1099-0518</idno><idno type="book-part-DOI">10.1002/pola.v45:3</idno><idno type="product">POLA</idno><imprint><biblScope unit="vol">45</biblScope><biblScope unit="issue">3</biblScope><biblScope unit="page" from="543">543</biblScope><biblScope unit="page" to="547">547</biblScope><biblScope unit="page-count">5</biblScope><publisher>Wiley Subscription Services, Inc., A Wiley Company</publisher><pubPlace>Hoboken</pubPlace><date type="published" when="2007-02-01"></date></imprint></monogr></biblStruct></sourceDesc></fileDesc><profileDesc><abstract xml:lang="en" style="main"><head>Abstract</head><p>To develop a novel polycondensation method for the preparation of poly (amino acid)s, we screened a transition metal or a rare‐earth triflate as a Lewis acid for the polycondensation of activated amino acid esters in <hi rend="italic">N,N</hi>‐dimethylformamide solutions at room temperature. The polymerizations of 4‐nitrophenyl <hi rend="smallCaps">L</hi>‐leucinate (<hi rend="bold">1a</hi>) and 4‐nitrophenyl <hi rend="smallCaps">L</hi>‐valinate (<hi rend="bold">1b</hi>) scarcely proceeded without any Lewis acid at room temperature. In the presence of 5 mol % metal triflates, especially scandium(III) trifluoromethanesulfonate, the polymerizations of both monomers were promoted effectively. The products, which were collected by the reaction mixture being poured into water, were recognized as poly(<hi rend="smallCaps">L</hi>‐valine)s by Fourier transform infrared spectroscopy, gel permeation chromatography analysis, and <hi rend="superscript">1</hi>H NMR spectroscopy. These results showed that a metal triflate as a Lewis acid could coordinate to a carbonyl oxygen of activated <hi rend="smallCaps">L</hi>‐valinate and <hi rend="smallCaps">L</hi>‐leucinate even in a highly polar solvent, such as <hi rend="italic">N,N</hi>‐dimethylformamide; therefore, the polymerizations of activated <hi rend="smallCaps">L</hi>‐valinate and <hi rend="smallCaps">L</hi>‐leucinate were promoted. Because steric hindrance derived from the isobutyl group in <hi rend="bold">1b</hi> was less than that of the isopropyl unit in <hi rend="bold">1a</hi>, the effect of the metals was not as sensitive for the polymerization of <hi rend="bold">1b</hi>. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 543–547, 2007</p></abstract><abstract xml:lang="en" style="graphical"><p>We screened a transition metal or a rare‐earth triflate as a Lewis acid for the polycondensation of 4‐nitrophenyl <hi rend="smallCaps">L</hi>‐leucinate and <hi rend="smallCaps">L</hi>‐valinate in <hi rend="italic">N,N</hi>‐dimethylformamide solutions at room temperature. In the presence of 5 mol % metal triflates, especially scandium(III) trifluoromethanesulfonate, the polymerizations of both monomers were promoted effectively. <figure type="box"><media mimeType="image" url="urn:x-wiley:0887624X:media:POLA21895:gra001"></media><media mimeType="image/gif" url="" rendition="webLoRes"></media><media mimeType="image/jpeg" url="" rendition="webOriginal"></media><media mimeType="image/jpeg" url="" rendition="webHiRes"></media></figure></p></abstract><textClass><keywords xml:lang="en"><term xml:id="kwd1">α‐amino acid ester</term><term xml:id="kwd2">catalysis</term><term xml:id="kwd3">Lewis acid</term><term xml:id="kwd4">oligomers</term><term xml:id="kwd5">polycondensation</term><term xml:id="kwd6">poly(α‐amino acid)s</term></keywords><keywords rend="articleCategory"><term>Article</term></keywords><keywords rend="tocHeading1"><term>Articles</term></keywords></textClass><langUsage><language ident="en"></language></langUsage></profileDesc></teiHeader></istex:fulltextTEI><json:item><extension>txt</extension><original>false</original><mimetype>text/plain</mimetype><uri>https://api.istex.fr/document/E2930119DC315E12AB45BE12F8F61EE06D16445B/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="Wiley, elements deleted: body"><istex:xmlDeclaration>version="1.0" encoding="UTF-8" standalone="yes"</istex:xmlDeclaration><istex:document><component version="2.0" type="serialArticle" xml:lang="en"><header><publicationMeta level="product"><publisherInfo><publisherName>Wiley Subscription Services, Inc., A Wiley Company</publisherName><publisherLoc>Hoboken</publisherLoc></publisherInfo><doi registered="yes">10.1002/(ISSN)1099-0518</doi><issn type="print">0887-624X</issn><issn type="electronic">1099-0518</issn><idGroup><id type="product" value="POLA"></id></idGroup><titleGroup><title type="main" xml:lang="en" sort="JOURNAL OF POLYMER SCIENCE PART A: POLYMER CHEMISTRY">Journal of Polymer Science Part A: Polymer Chemistry</title><title type="short">J. Polym. Sci. A Polym. Chem.</title></titleGroup></publicationMeta><publicationMeta level="part" position="30"><doi origin="wiley" registered="yes">10.1002/pola.v45:3</doi><numberingGroup><numbering type="journalVolume" number="45">45</numbering><numbering type="journalIssue">3</numbering></numberingGroup><coverDate startDate="2007-02-01">1 February 2007</coverDate></publicationMeta><publicationMeta level="unit" type="article" position="200" status="forIssue"><doi origin="wiley" registered="yes">10.1002/pola.21895</doi><idGroup><id type="unit" value="POLA21895"></id></idGroup><countGroup><count type="pageTotal" number="5"></count></countGroup><titleGroup><title type="articleCategory">Article</title><title type="tocHeading1">Articles</title></titleGroup><copyright ownership="publisher">Copyright © 2006 Wiley Periodicals, Inc.</copyright><eventGroup><event type="manuscriptReceived" date="2006-10-11"></event><event type="manuscriptAccepted" date="2006-11-20"></event><event type="firstOnline" date="2006-12-15"></event><event type="publishedOnlineFinalForm" date="2006-12-15"></event><event type="xmlConverted" agent="Converter:JWSART34_TO_WML3G version:2.3.6 mode:FullText source:FullText result:FullText" date="2010-04-23"></event><event type="xmlConverted" agent="Converter:WILEY_ML3G_TO_WILEY_ML3GV2 version:3.8.8" date="2014-02-07"></event><event type="xmlConverted" agent="Converter:WML3G_To_WML3G version:4.1.7 mode:FullText,remove_FC" date="2014-10-30"></event></eventGroup><numberingGroup><numbering type="pageFirst">543</numbering><numbering type="pageLast">547</numbering></numberingGroup><correspondenceTo>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan</correspondenceTo><objectNameGroup><objectName elementName="figure">Scheme</objectName></objectNameGroup><linkGroup><link type="toTypesetVersion" href="file:POLA.POLA21895.pdf"></link></linkGroup></publicationMeta><contentMeta><countGroup><count type="figureTotal" number="4"></count><count type="tableTotal" number="1"></count><count type="referenceTotal" number="13"></count><count type="wordTotal" number="2762"></count></countGroup><titleGroup><title type="main" xml:lang="en">Polycondensation of activated <sc>L</sc>‐valine and <sc>L</sc>‐leucine esters with various lewis acids</title><title type="short" xml:lang="en">Polycondensation with Various Lewis Acids</title></titleGroup><creators><creator xml:id="au1" creatorRole="author" affiliationRef="#af1"><personName><givenNames>Tadamasa</givenNames><familyName>Nemoto</familyName></personName></creator><creator xml:id="au2" creatorRole="author" affiliationRef="#af1"><personName><givenNames>Daisuke</givenNames><familyName>Ando</familyName></personName></creator><creator xml:id="au3" creatorRole="author" affiliationRef="#af1" corresponding="yes"><personName><givenNames>Kensuke</givenNames><familyName>Naka</familyName></personName><contactDetails><email normalForm="ken@chujo.synchem.kyoto-u.ac.jp">ken@chujo.synchem.kyoto‐u.ac.jp</email></contactDetails></creator><creator xml:id="au4" creatorRole="author" affiliationRef="#af1"><personName><givenNames>Yoshiki</givenNames><familyName>Chujo</familyName></personName></creator></creators><affiliationGroup><affiliation xml:id="af1" countryCode="JP" type="organization"><unparsedAffiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan</unparsedAffiliation></affiliation></affiliationGroup><keywordGroup xml:lang="en" type="author"><keyword xml:id="kwd1">α‐amino acid ester</keyword><keyword xml:id="kwd2">catalysis</keyword><keyword xml:id="kwd3">Lewis acid</keyword><keyword xml:id="kwd4">oligomers</keyword><keyword xml:id="kwd5">polycondensation</keyword><keyword xml:id="kwd6">poly(α‐amino acid)s</keyword></keywordGroup><abstractGroup><abstract type="main" xml:lang="en"><title type="main">Abstract</title><p>To develop a novel polycondensation method for the preparation of poly (amino acid)s, we screened a transition metal or a rare‐earth triflate as a Lewis acid for the polycondensation of activated amino acid esters in <i>N,N</i>‐dimethylformamide solutions at room temperature. The polymerizations of 4‐nitrophenyl <sc>L</sc>‐leucinate (<b>1a</b>) and 4‐nitrophenyl <sc>L</sc>‐valinate (<b>1b</b>) scarcely proceeded without any Lewis acid at room temperature. In the presence of 5 mol % metal triflates, especially scandium(III) trifluoromethanesulfonate, the polymerizations of both monomers were promoted effectively. The products, which were collected by the reaction mixture being poured into water, were recognized as poly(<sc>L</sc>‐valine)s by Fourier transform infrared spectroscopy, gel permeation chromatography analysis, and <sup>1</sup>H NMR spectroscopy. These results showed that a metal triflate as a Lewis acid could coordinate to a carbonyl oxygen of activated <sc>L</sc>‐valinate and <sc>L</sc>‐leucinate even in a highly polar solvent, such as <i>N,N</i>‐dimethylformamide; therefore, the polymerizations of activated <sc>L</sc>‐valinate and <sc>L</sc>‐leucinate were promoted. Because steric hindrance derived from the isobutyl group in <b>1b</b> was less than that of the isopropyl unit in <b>1a</b>, the effect of the metals was not as sensitive for the polymerization of <b>1b</b>. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 543–547, 2007</p></abstract><abstract type="graphical" xml:lang="en"><p>We screened a transition metal or a rare‐earth triflate as a Lewis acid for the polycondensation of 4‐nitrophenyl <sc>L</sc>‐leucinate and <sc>L</sc>‐valinate in <i>N,N</i>‐dimethylformamide solutions at room temperature. In the presence of 5 mol % metal triflates, especially scandium(III) trifluoromethanesulfonate, the polymerizations of both monomers were promoted effectively. <blockFixed type="graphic"><mediaResourceGroup><mediaResource alt="image" eRights="yes" copyright="Wiley Periodicals, Inc." href="urn:x-wiley:0887624X:media:POLA21895:gra001"></mediaResource><mediaResource alt="thumbnail image" rendition="webLoRes" mimeType="image/gif" href=""></mediaResource><mediaResource alt="original image" rendition="webOriginal" mimeType="image/jpeg" href=""></mediaResource><mediaResource alt="magnified image" rendition="webHiRes" mimeType="image/jpeg" href=""></mediaResource></mediaResourceGroup></blockFixed></p></abstract></abstractGroup></contentMeta></header></component></istex:document></istex:metadataXml><mods version="3.6"><titleInfo lang="en"><title>Polycondensation of activated L‐valine and L‐leucine esters with various lewis acids</title></titleInfo><titleInfo type="abbreviated" lang="en"><title>Polycondensation with Various Lewis Acids</title></titleInfo><titleInfo type="alternative" contentType="CDATA" lang="en"><title>Polycondensation of activated L‐valine and L‐leucine esters with various lewis acids</title></titleInfo><name type="personal"><namePart type="given">Tadamasa</namePart><namePart type="family">Nemoto</namePart><affiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Daisuke</namePart><namePart type="family">Ando</namePart><affiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Kensuke</namePart><namePart type="family">Naka</namePart><affiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan</affiliation><affiliation>E-mail: ken@chujo.synchem.kyoto‐u.ac.jp</affiliation><affiliation>Correspondence address: Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Yoshiki</namePart><namePart type="family">Chujo</namePart><affiliation>Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo‐Ku, Kyoto 615‐8510, Japan</affiliation><role><roleTerm type="text">author</roleTerm></role></name><typeOfResource>text</typeOfResource><genre type="article" displayLabel="article" authority="ISTEX" authorityURI="https://content-type.data.istex.fr" valueURI="https://content-type.data.istex.fr/ark:/67375/XTP-6N5SZHKN-D">article</genre><originInfo><publisher>Wiley Subscription Services, Inc., A Wiley Company</publisher><place><placeTerm type="text">Hoboken</placeTerm></place><dateIssued encoding="w3cdtf">2007-02-01</dateIssued><dateCaptured encoding="w3cdtf">2006-10-11</dateCaptured><dateValid encoding="w3cdtf">2006-11-20</dateValid><copyrightDate encoding="w3cdtf">2007</copyrightDate></originInfo><language><languageTerm type="code" authority="rfc3066">en</languageTerm><languageTerm type="code" authority="iso639-2b">eng</languageTerm></language><physicalDescription><extent unit="figures">4</extent><extent unit="tables">1</extent><extent unit="references">13</extent><extent unit="words">2762</extent></physicalDescription><abstract>To develop a novel polycondensation method for the preparation of poly (amino acid)s, we screened a transition metal or a rare‐earth triflate as a Lewis acid for the polycondensation of activated amino acid esters in N,N‐dimethylformamide solutions at room temperature. The polymerizations of 4‐nitrophenyl L‐leucinate (1a) and 4‐nitrophenyl L‐valinate (1b) scarcely proceeded without any Lewis acid at room temperature. In the presence of 5 mol % metal triflates, especially scandium(III) trifluoromethanesulfonate, the polymerizations of both monomers were promoted effectively. The products, which were collected by the reaction mixture being poured into water, were recognized as poly(L‐valine)s by Fourier transform infrared spectroscopy, gel permeation chromatography analysis, and 1H NMR spectroscopy. These results showed that a metal triflate as a Lewis acid could coordinate to a carbonyl oxygen of activated L‐valinate and L‐leucinate even in a highly polar solvent, such as N,N‐dimethylformamide; therefore, the polymerizations of activated L‐valinate and L‐leucinate were promoted. Because steric hindrance derived from the isobutyl group in 1b was less than that of the isopropyl unit in 1a, the effect of the metals was not as sensitive for the polymerization of 1b. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 543–547, 2007</abstract><abstract type="graphical" lang="en">We screened a transition metal or a rare‐earth triflate as a Lewis acid for the polycondensation of 4‐nitrophenyl L‐leucinate and L‐valinate in N,N‐dimethylformamide solutions at room temperature. In the presence of 5 mol % metal triflates, especially scandium(III) trifluoromethanesulfonate, the polymerizations of both monomers were promoted effectively.</abstract><subject lang="en"><genre>keywords</genre><topic>α‐amino acid ester</topic><topic>catalysis</topic><topic>Lewis acid</topic><topic>oligomers</topic><topic>polycondensation</topic><topic>poly(α‐amino acid)s</topic></subject><relatedItem type="host"><titleInfo><title>Journal of Polymer Science Part A: Polymer Chemistry</title></titleInfo><titleInfo type="abbreviated"><title>J. Polym. Sci. A Polym. Chem.</title></titleInfo><genre type="journal" authority="ISTEX" authorityURI="https://publication-type.data.istex.fr" valueURI="https://publication-type.data.istex.fr/ark:/67375/JMC-0GLKJH51-B">journal</genre><subject><genre>article-category</genre><topic>Article</topic></subject><identifier type="ISSN">0887-624X</identifier><identifier type="eISSN">1099-0518</identifier><identifier type="DOI">10.1002/(ISSN)1099-0518</identifier><identifier type="PublisherID">POLA</identifier><part><date>2007</date><detail type="volume"><caption>vol.</caption><number>45</number></detail><detail type="issue"><caption>no.</caption><number>3</number></detail><extent unit="pages"><start>543</start><end>547</end><total>5</total></extent></part></relatedItem><identifier type="istex">E2930119DC315E12AB45BE12F8F61EE06D16445B</identifier><identifier type="ark">ark:/67375/WNG-T5K5V41X-H</identifier><identifier type="DOI">10.1002/pola.21895</identifier><identifier type="ArticleID">POLA21895</identifier><accessCondition type="use and reproduction" contentType="copyright">Copyright © 2006 Wiley Periodicals, Inc.</accessCondition><recordInfo><recordContentSource authority="ISTEX" authorityURI="https://loaded-corpus.data.istex.fr" valueURI="https://loaded-corpus.data.istex.fr/ark:/67375/XBH-L0C46X92-X">wiley</recordContentSource><recordOrigin>Wiley Subscription Services, Inc., A Wiley Company</recordOrigin></recordInfo></mods><json:item><extension>json</extension><original>false</original><mimetype>application/json</mimetype><uri>https://api.istex.fr/document/E2930119DC315E12AB45BE12F8F61EE06D16445B/metadata/json</uri></json:item></metadata><serie></serie></istex></record>Pour manipuler ce document sous Unix (Dilib)
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