<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1870-249X</journal-id>
<journal-title><![CDATA[Journal of the Mexican Chemical Society]]></journal-title>
<abbrev-journal-title><![CDATA[J. Mex. Chem. Soc]]></abbrev-journal-title>
<issn>1870-249X</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Química de México A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1870-249X2006000300010</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Catalytic Synthesis of 1,3,5-Triphenylbenzenes, &#946;-Methylchalcones and 2,4,6-Triphenyl Pyrylium Salts, Promoted by a Super Acid Triflouromethane Sulfonic Clay from Acetophenones]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ruíz-Guerrero]]></surname>
<given-names><![CDATA[Rosario]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cárdenas]]></surname>
<given-names><![CDATA[Jorge]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Bautista]]></surname>
<given-names><![CDATA[Lorena]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Vargas]]></surname>
<given-names><![CDATA[Marina]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
<xref ref-type="aff" rid="A03"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Vázquez-Labastida]]></surname>
<given-names><![CDATA[Eloy]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Salmón]]></surname>
<given-names><![CDATA[Manuel]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad Nacional Autónoma de México Instituto de Química ]]></institution>
<addr-line><![CDATA[México Distrito Federal]]></addr-line>
<country>México</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Instituto Politécnico Nacional Escuela Superior de Ingeniería Química e Industrias Extractivas ]]></institution>
<addr-line><![CDATA[México Distrito Federal]]></addr-line>
<country>México</country>
</aff>
<aff id="A03">
<institution><![CDATA[,Universidad Nacional Autónoma de México Facultad de Estudios Superiores Cuautitlán Departamento de Química]]></institution>
<addr-line><![CDATA[México Distrito Federal]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>09</month>
<year>2006</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>09</month>
<year>2006</year>
</pub-date>
<volume>50</volume>
<numero>3</numero>
<fpage>114</fpage>
<lpage>118</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1870-249X2006000300010&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1870-249X2006000300010&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1870-249X2006000300010&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[A montmorillonite clay from the State of Durango, Mexico, was used as catalyst. The clay was activated with trifluo-romethane sulfonic acid and used to study the condensation of different acetophenones in refluxing benzene to produce triphenylbenzenes, &#946;-methylchalcones and pyrylium salts. This catalytic procedure afforded a new simple one-step method for the synthesis of complex organic molecules through the C-C bonds formation and the counter ion for the pyrylium salt. A proposed mechanism of the isolated compounds is discussed as well as their identification by spectroscopic methods and by comparison with reported data, acquired from the previously synthesized derivatives by other synthetic methods.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Una arcilla de montmorilonita del estado de Durango se empleó como catalizador. La arcilla fue activada con ácido trifluoro-metansulfónico y usada para estudiar la condensación de diferentes acetofenonas en benceno a reflujo para producir trifenilbencenos, &#946;-metilchalconas y sales de pirilio. Este proceso catalítico produjo un nuevo método en una sola etapa para la síntesis de moléculas complejas a través de la formación de enlaces C-C con el contraión del ácido en el pirilio. Se discute la propuesta mecanística para la formación de los compuestos aislados, así como su identificación por métodos espectroscópicos y por comparación con datos informados, adquiridos por derivados previamente sintetizados por otros métodos.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Heterogeneous Catalysis]]></kwd>
<kwd lng="en"><![CDATA[Trifluoromethane sulfonic Clays]]></kwd>
<kwd lng="en"><![CDATA[Acetophenones]]></kwd>
<kwd lng="en"><![CDATA[Triphenylbenzenes]]></kwd>
<kwd lng="en"><![CDATA[&#946;-Methylchalcones]]></kwd>
<kwd lng="en"><![CDATA[Pyrylium salts]]></kwd>
<kwd lng="es"><![CDATA[Catálisis heterogénea]]></kwd>
<kwd lng="es"><![CDATA[arcilla trifluorometansulfónica]]></kwd>
<kwd lng="es"><![CDATA[acetofenonas]]></kwd>
<kwd lng="es"><![CDATA[trifenilbencenos]]></kwd>
<kwd lng="es"><![CDATA[&#946;-metilchalconas]]></kwd>
<kwd lng="es"><![CDATA[sales de pirilio]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  	    <p align="justify"><font face="verdana" size="4">Article</font></p> 	    <p align="justify">&nbsp;</p> 	    <p align="center"><font face="verdana" size="4"><b>Catalytic Synthesis of 1,3,5&#45;Triphenylbenzenes,</b> <b>&beta;&#45;Methylchalcones and 2,4,6&#45;Triphenyl Pyrylium Salts, Promoted by a Super Acid Triflouromethane Sulfonic Clay from Acetophenones</b></font></p>     <p align="justify">&nbsp;</p> 	    <p align="center"><font face="verdana" size="2"><b>Rosario Ru&iacute;z&#45;Guerrero,<sup>1</sup> Jorge C&aacute;rdenas,<sup>1</sup> Lorena Bautista,<sup>1</sup> Marina Vargas,<sup>1,3</sup> Eloy V&aacute;zquez&#45;Labastida<sup>2</sup> and Manuel Salm&oacute;n*<sup>1</sup></b><sup></sup></font></p> 	    <p align="justify">&nbsp;</p> 	    <p align="justify"><font face="verdana" size="2"><sup><i>1</i></sup><i>&nbsp;Instituto de Qu&iacute;mica de la Universidad Nacional Aut&oacute;noma de M&eacute;xico, Circuito Exterior, Ciudad Universitaria, Coyoac&aacute;n 04510, M&eacute;xico D. F.</i> <a href="mailto:salmon@servidor.unam.mx">salmon@servidor.unam.mx</a></font></p> 	    <p align="justify"><font face="verdana" size="2"><sup><i>2</i></sup><i>&nbsp;Escuela Superior de Ingenier&iacute;a Qu&iacute;mica e Industrias Extractivas del Instituto Polit&eacute;cnico Nacional, Edificio 7, Unidad Profesional, Zacatenco, Col. La Escalera, M&eacute;xico 07038, D. F.</i></font></p> 	    <p align="justify"><i><font face="verdana" size="2"><sup>3</sup> Departamento de Qu&iacute;mica, Facultad de Estudios Superiores Cuautitl&aacute;n, Universidad Nacional Aut&oacute;noma de M&eacute;xico, Cuautitl&aacute;n Izcalli, Estado de M&eacute;xico, M&eacute;xico 54740.</font></i><font face="verdana" size="2"></font></p> 	    ]]></body>
<body><![CDATA[<p align="justify">&nbsp;</p> 	    <p align="justify"><font face="verdana" size="2">Recibido el 9 de marzo del 2006.     <br>     Aceptado el 31 de mayo del 2006.</font></p>     <p align="justify">&nbsp;</p> 	    <p align="justify"><font face="verdana" size="2"><b>Abstract</b></font></p> 	    <p align="justify"><font face="verdana" size="2"> A montmorillonite clay from the State of Durango, Mexico, was used as catalyst. The clay was activated with trifluo&#45;romethane sulfonic acid and used to study the condensation of different acetophenones in refluxing benzene to produce triphenylbenzenes, &beta;&#45;methylchalcones and pyrylium salts. This catalytic procedure afforded a new simple one&#45;step method for the synthesis of complex organic molecules through the C&#45;C bonds formation and the counter ion for the pyrylium salt. A proposed mechanism of the isolated compounds is discussed as well as their identification by spectroscopic methods and by comparison with reported data, acquired from the previously synthesized derivatives by other synthetic methods.</font></p> 	    <p align="justify"><font face="verdana" size="2"><b>Keywords: </b>Heterogeneous Catalysis, Trifluoromethane sulfonic Clays, Acetophenones, Triphenylbenzenes, &beta;&#45;Methylchalcones, Pyrylium salts.</font></p> 	    <p align="justify">&nbsp;</p> 	    <p align="justify"><font face="verdana" size="2"><b>Resumen</b></font></p>     <p align="justify"><font face="verdana" size="2"> Una arcilla de montmorilonita del estado de Durango se emple&oacute; como catalizador. La arcilla fue activada con &aacute;cido trifluoro&#45;metansulf&oacute;nico y usada para estudiar la condensaci&oacute;n de diferentes acetofenonas en benceno a reflujo para producir trifenilbencenos, &beta;<b>&#45;</b>metilchalconas y sales de pirilio. Este proceso catal&iacute;tico produjo un nuevo m&eacute;todo en una sola etapa para la s&iacute;ntesis de mol&eacute;culas complejas a trav&eacute;s de la formaci&oacute;n de enlaces C&#45;C con el contrai&oacute;n del &aacute;cido en el pirilio. Se discute la propuesta mecan&iacute;stica para la formaci&oacute;n de los compuestos aislados, as&iacute; como su identificaci&oacute;n por m&eacute;todos espectrosc&oacute;picos y por comparaci&oacute;n con datos informados, adquiridos por derivados previamente sintetizados por otros m&eacute;todos. </font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2"><b>Palabras clave:</b> Cat&aacute;lisis heterog&eacute;nea, arcilla trifluorometansulf&oacute;nica, acetofenonas, trifenilbencenos, &beta;&#45;metilchalconas, sales de pirilio.</font></p>     <p align="justify">&nbsp;</p>     <p align="justify"><font size="2" face="verdana"><a href="/pdf/jmcs/v50n3/v50n3a10.pdf" target="_blank">DESCARGAR ARCHIVO EN FORMATO PDF</a></font></p>     <p align="justify">&nbsp;</p>     <p align="justify"><font size="2" face="verdana"><b>Acknowledgment</b></font></p>     <p align="justify"><font face="verdana" size="2">M. Salm&oacute;n and M. Vargas gratefully acknowledge the financial support to DGAPA&#45;PAPIIT IN104900, DGAPA&#45;IN500597, DGAPA&#45;IN215598 and CONACyT 25267&#45;A</font></p>  	    <p align="justify"><font face="verdana" size="2">The authors wish to thank C. Dami&aacute;n, A. Pe&ntilde;a, B. Quiroz and N. Zavala, for technical assistance.</font></p> 	    <p align="justify">&nbsp;</p> 	    <p align="justify"><font face="verdana" size="2"><b>References</b></font></p> 	    <!-- ref --><p align="justify"><font face="verdana" size="2">1. Salm&oacute;n, M.; Penieres, G.; Miranda, R. <i>J. Heterocyclic Chem.</i> <b>1980,</b> <i>18</i>, 1475&#45;1476;    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4965281&pid=S1870-249X200600030001000001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --> Miranda&#45;Ruvalcaba, R.; Arrollo&#45;Razo, G. A.; Penieres&#45;Carrillo, G.; Delgado&#45;Reyes, F.; Cabrera&#45;Ortiz, A.; Alvarez&#45;Toledano, C.; Salm&oacute;n Salazar, M. <i>Trends Heterocyclic Chem.</i> <b>2003,</b> <i>9</i>, 195&#45;235.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4965282&pid=S1870-249X200600030001000002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">2. Elderfield, R. C.; King, T. P. <i>J. Am. Chem. Soc</i> <b>1954,</b> <i>76</i>, 5437&#45;5439.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4965284&pid=S1870-249X200600030001000003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">3. Bello, A. M.; Kotra, L. <i>Tetrahedron Lett.</i> <b>2003,</b> <i>44</i>, 9271&#45;9274.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4965286&pid=S1870-249X200600030001000004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">4. Barry&#45;Kone, N.; Fossey, J.; Loupy, A.; Sib, S.; Simalty, M.; Sorba, <i>Bull. Soc. Chim. Fr.</i> <b>1993,</b> <i>130</i>, 218&#45;222.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4965288&pid=S1870-249X200600030001000005&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">5. Salm&oacute;n, M.; P&eacute;rez&#45;Luna, M.; L&oacute;pez&#45;Franco, C.; Hern&aacute;ndez, E.; Alvarez&#45;Ramirez, R. A.; L&oacute;pez&#45;Ortega, A.; Dom&iacute;nguez, J. M. <i>J. Mol. Cat. A: Chem.</i> <b>1997,</b> <i>122,</i> 169&#45;174.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4965290&pid=S1870-249X200600030001000006&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     ]]></body>
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