01919nas a2200205   4500008004100000022001400041245018300055210006900238260007300307300001200380490000600392520104200398653002401440653004001464653002501504100001901529700002001548700001801568856012701586       2007                        eng d  a1566-736700aBenzylsulfonic acid functionalized mesoporous Zr-TMS catalysts: an efficient and recyclable catalyst for the preparation of coumarin derivatives by pechmann condensation reaction0 aBenzylsulfonic acid functionalized mesoporous ZrTMS catalysts an  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAY  a777-7830 v83 a<p>Benzylsulfonic acid functionalized mesoporous Zr-TMS (Zr-TMS-BSA, Zr-TMS, zirconia based transition metal oxide mesoporous molecular sieves) catalyst is used as an alternative to conventional acid catalysts in the von Pechmann condensation of aromatic alcohols with ethyl acetoacetate leading to the formation of coumarin derivatives in solvent free condition at 150 degrees C. Three types of coumarins, 7-hydroxy-4-methylcoumarin (beta-methylumbelliferone), 7-methoxy-4-methylcoumarin (Methyl-4-methylumbelliferyl ether) and 7,8-benzo-4-methylcoumarin derivatives have been prepared using resorcinol, 3-methoxyphenol and 1-naphthol, respectively. The catalytic activity and the recycle studies of the catalyst in all the three reactions proved the superior performance of the catalyst. Further the products were confirmed by GC, elemental analysis, melting point and NMR techniques. Finally, the probable mechanism for Pechmarm condensation using Zr-TMS-BSA catalyst has been reported. (c) 2006 Elsevier B.V. All rights reserved.</p>10abenzylsulfonic acid10aPechmann condensation and coumarins10aZr-TMS-BSA catalysts1 aSelvakumar, S.1 aChidambaram, M.1 aSingh, A., P.  uhttps://library.ncl.res.in/content/benzylsulfonic-acid-functionalized-mesoporous-zr-tms-catalysts-efficient-and-recyclable