SiO2-Supported CeCl3·7H2O-NaI Lewis Acid Promoter: Investigation into the Garcia Gonzalez Reaction in Solvent-Free Conditionssrc="http://pubs.acs.org/im

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• 作者：Giuseppe Bartoli ; José ; G. Fern&aacute ; ndez-Bolañ ; os ; Giustino Di Antonio ; Gioia Foglia ; Sandra Giuli ; Roberto Gunnella ; Michele Mancinelli ; Enrico Marcantoni ; Melissa Paoletti
• 刊名：Journal of Organic Chemistry
• 出版年：2007
• 出版时间：August 3, 2007
• 年：2007
• 卷：72
• 期：16
• 页码：6029 - 6036
• 全文大小：147K
• 年卷期：v.72,no.16(August 3, 2007)
• ISSN：1520-6904

文摘

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The Knoevenagel condensation of aldose sugars with s/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-dicarbonyl compounds produces furan derivativeshaving polyhydroxyalkylated alkyl side chains; this reaction is known as the Garcia Gonzalez reaction.Despite the fact that these polyhydroxyalkyl furans are interesting scaffolds for synthetic chemists toutilize in the synthesis of a variety of biologically interesting molecules, the reported approach suffersfrom harsh conditions. The development of a general and more efficient protocol is of considerableimportance, and in this manuscript, we wish to explore the role of the NaI in enhancing the activity ofCeCl₃·7H₂O as a useful water-tolerant Lewis acid promoter for the Garcia Gonzalez reaction. The procedureproceeds with good yields at 50 s/entities/deg.gif">C using our system supported on SiO₂ in solvent-free conditions andrepresents a simple and convenient methodology for the preparation of densely functionalized molecules.Furthermore, the first qualitative results obtained on mechanistic investigation on the role of iodide onthis our heterogeneous reaction may be of value for optimization of existing organic transformations andfor the development of new ones.