01885nas a2200241 4500008004100000022001400041245015500055210006900210260007300279300001200352490000800364520095600372653002601328653001901354653002201373653002001395653002101415653002301436100001901459700002001478700001801498856012701516 2005 eng d a0926-860X00a3-Aminopropyltriethoxysilyl functionalized Na-Al-MCM-41 solid base catalyst for selective preparation of 2-phenylpropionitrile from phenylacetonitrile0 a3Aminopropyltriethoxysilyl functionalized NaAlMCM41 solid base c aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcSEP a344-3530 v2923 a

Various solid base catalysts have been prepared by ion exchange of zeolites and Na-Al-MCM-41 and by organosilane grafting over mesoporous materials. Base catalysts thus synthesized were studied in the selective monomethylation of phenylacetonitrile (PAN) to 2-phenylpropionitrile (2-PPN) using dimethylcarbonate (DMC) as an alkylating agent in a Parr autoclave at a temperature ranging between 443 and 473 K and at autogenously developed pressure. NH2-Na-Al-MCM-41 (30) showed a high activity, and the optimum loading of 3-aminopropyltriethoxysilyl (3-APTES) was found to be 1.35 mmol g(-1), being consistent with the structural characterization. Co-condensation of 3-APTES, tetraethylorthosilicate (TEOS) and sodiumaluminate in the presence of surfactant provides a material with uniformly distributed basic sites responsible for high activity in the selective monomethylation of phenylacetonitrile. (c) 2005 Elsevier B.V. All rights reserved.

10a2-phenylpropionitrile10abase catalysis10adimethylcarbonate10amonomethylation10aNH2-Na-Al-MCM-4110aphenylacetonitrile1 aVenkatesan, C.1 aChidambaram, M.1 aSingh, A., P. uhttps://library.ncl.res.in/content/3-aminopropyltriethoxysilyl-functionalized-na-al-mcm-41-solid-base-catalyst-selective-002066nas a2200229 4500008004100000022001400041245014400055210006900199260007300268300001000341490000800351520116400359653001801523653002801541653002001569653003001589653003001619100002001649700001901669700001801688856013001706 2006 eng d a0926-860X00aOrganosilanesulfonic acid-functionalized Zr-TMS catalysts: synthesis, characterization and catalytic applications in condensation reactions0 aOrganosilanesulfonic acidfunctionalized ZrTMS catalysts synthesi aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAUG a79-900 v3103 a

Organosilanesulfonic acid (-Si-R3S-R4SO3H, OSA)-functionalized mesoporous Zr-TMS (Zr-TMS-Si-R3S-R4SO3H, Zr-TMS-OSA) was synthesized either by post-synthetic modification of Zr-TMS (zirconia-based transition metal oxide mesoporous molecular sieves) with 3-mercaptopropyltrimethoxysilane (3-MPTS) and further with 1,4-butanesultone (1,4-BS) or by in situ one-pot synthesis procedure. A number of physico-chemical characterization techniques have been used to show that the organosilanesulfonic acid groups were anchored on to the walls of Zr-TMS. MCM-41-Si-R3S-R4SO3H-20 (MCM-41-OSA-20) was also prepared by post-synthesis procedure for comparison. Physico-chemical properties of in situ made A-Zr-OSA-20, Zr-TMS-SO3H-20 and MCM-41-OSA-20 were compared with Zr-TMS-OSA catalysts. The catalytic activity of the materials was tested in liquid phase condensation of aniline with p-formaldehyde to 4,4'-diaminodiphenylmethane (4,4'-DADPM). Results showed that Zr-TMS-OSA catalysts were more active than Zr-TMS-SO3H-20, MCM-41-OSA-20 and A-Zr-OSA-20 and more selective than Zr-TMS-SO3H-20 and A-Zr-OSA-20 catalysts. (C) 2006 Elsevier B.V. All rights reserved.

10aAcid catalyst10acondensation of aniline10amesoporous ZrO210aorganic functionalization10aorganosilanesulfonic acid1 aChidambaram, M.1 aVenkatesan, C.1 aSingh, A., P. uhttps://library.ncl.res.in/content/organosilanesulfonic-acid-functionalized-zr-tms-catalysts-synthesis-characterization-and-001919nas 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

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.

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