<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sankar, M.</style></author><author><style face="normal" font="default" size="100%">Nair, C. Madhavan</style></author><author><style face="normal" font="default" size="100%">Murty, K. V. G. K.</style></author><author><style face="normal" font="default" size="100%">Manikandan, Palanichamy</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transesterification of cyclic carbonates with methanol at ambient conditions over tungstate-based solid catalysts</style></title><secondary-title><style face="normal" font="default" size="100%">Applied Catalysis A-General</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Dimethyl carbonate</style></keyword><keyword><style  face="normal" font="default" size="100%">ethylene carbonate</style></keyword><keyword><style  face="normal" font="default" size="100%">heterogeneous catalyst</style></keyword><keyword><style  face="normal" font="default" size="100%">Raman spectroscopy</style></keyword><keyword><style  face="normal" font="default" size="100%">sodium tungstate</style></keyword><keyword><style  face="normal" font="default" size="100%">transesterification</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">SEP</style></date></pub-dates></dates><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE BV</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS</style></pub-location><volume><style face="normal" font="default" size="100%">312</style></volume><pages><style face="normal" font="default" size="100%">108-114</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Dimethyl carbonate synthesis with 80 mol% yield is achieved through transesterification of ethylene carbonate with methanol at ambient conditions (RT and atmospheric pressure) using alkali and alkaline-earth tungstates as solid catalysts. The catalysts are efficient even at the sub-ambient temperatures. Reactions under CO2 pressure indicate that CO2 atmosphere retards the transesterification reaction completely below 100 degrees C. Experimental conditions of 150 degrees C and 3.4 MPa CO2 pressure are required to obtain maximum DMC yield of 71 mol%. Synthesis of DMC by one-pot synthesis using epoxide, CO2 and methanol is not as effective as that by two-step method with the present catalyst system. Raman and IR spectra of methanol-interacting tungstates indicate the formation of a methoxide ion species adsorbed at the catalyst surface as one possible reaction intermediates. (C) 2006 Elsevier B.V. All rights reserved.&lt;/p&gt;</style></abstract><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;</style></custom3><custom4><style face="normal" font="default" size="100%">4.012</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Upare, Pravin P.</style></author><author><style face="normal" font="default" size="100%">Kinage, Anil K.</style></author><author><style face="normal" font="default" size="100%">Shingote, Savita K.</style></author><author><style face="normal" font="default" size="100%">Gupte, Sunil P.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Environmentally benign synthesis of beta-hydroxy sulfides using cyclic carbonates catalyzed by large-pore zeolites</style></title><secondary-title><style face="normal" font="default" size="100%">Green Chemistry Letters and Reviews</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">beta-hydroxy sulfide</style></keyword><keyword><style  face="normal" font="default" size="100%">ethylene carbonate</style></keyword><keyword><style  face="normal" font="default" size="100%">propylene carbonate</style></keyword><keyword><style  face="normal" font="default" size="100%">thiophenol</style></keyword><keyword><style  face="normal" font="default" size="100%">zeolite</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2012</style></year><pub-dates><date><style  face="normal" font="default" size="100%">AUG</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">1</style></number><publisher><style face="normal" font="default" size="100%">TAYLOR &amp; FRANCIS LTD</style></publisher><pub-location><style face="normal" font="default" size="100%">4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND</style></pub-location><volume><style face="normal" font="default" size="100%">5</style></volume><pages><style face="normal" font="default" size="100%">19-26</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;An efficient one-pot synthesis of beta-hydroxy sulfides from thiophenol and cyclic carbonates catalyzed by large-pore zeolites has been reported. Reaction of thiophenol with ethylene carbonate in the presence of the Na-X zeolite catalyst gave the highest yield of 2-(phenylthio)ethanol (100%), while reaction with propylene carbonate a highest yield of regioselective product 1-(phenylthio)propan-2-ol was obtained (97%). Enantiomerically pure 1,2-propylene carbonate gave highly regioselective and stereospecific phenylthiopropanol, demonstrating that original chirality of propylene carbonate is retained. A plausible mechanism has been proposed for zeolite-catalyzed transformation involving a chemoselective nucleophilic attack of thiophenoloxide ion onto the less-substituted carbon of cyclic carbonate. The Na-X zeolite catalyst is recyclable and provides advantages of green chemistry approach to the synthesis of beta-hydroxy sulfides without the use of any solvent.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom3><style face="normal" font="default" size="100%">Foreign
</style></custom3><custom4><style face="normal" font="default" size="100%">1.392
</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nivangune, N. T.</style></author></authors><secondary-authors><author><style face="normal" font="default" size="100%">Ranade, V. V.</style></author></secondary-authors><tertiary-authors><author><style face="normal" font="default" size="100%">Kelkar, A. A.</style></author></tertiary-authors></contributors><titles><title><style face="normal" font="default" size="100%">MgFeCe ternary layered double hydroxide as highly efficient and recyclable heterogeneous base catalyst for synthesis of dimethyl carbonate by transesterification</style></title><secondary-title><style face="normal" font="default" size="100%">Catalysis Letters</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Dimethyl carbonate</style></keyword><keyword><style  face="normal" font="default" size="100%">ethylene carbonate</style></keyword><keyword><style  face="normal" font="default" size="100%">Mg–Fe–Ce Ternary Hydrotalcite</style></keyword><keyword><style  face="normal" font="default" size="100%">transesterification</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2017</style></year><pub-dates><date><style  face="normal" font="default" size="100%">OCT</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">147</style></volume><pages><style face="normal" font="default" size="100%"> 2558-2569</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A series of Mg3:Fex + Ce1−x LDHs (3:1) were synthesized by co-precipitation method by varying molar ratio of Fe:Ce between 1:0 to 0:1 (LDH-1 to LDH-6). All synthesized LDHs were characterized by XRD, FT-IR, TEM, N2 sorption, benzoic acid titration and XPS in detail and evaluated for selective synthesis of dimethyl carbonate by transesterification of ethylene carbonate with methanol. It was demonstrated that the structural and basic properties of synthesized LDHs were strongly dependent on the Fe:Ce molar ratio (Ce concentration). The correlation between their physicochemical properties and catalytic performance was studied in detail. Among all synthesized LDHs the best result was obtained with LDH-3 (Fe:Ce = 0.85:0.15) where LDH structure remained intact, and showed high number of strong basic sites on LDH surface. LDH-3 was recycled 7 times while maintaining high catalyst activity and selectivity towards DMC. The obtained results elucidate the important role of Ce in modifying the basic properties of LDH in enhancing the catalytic activity for DMC synthesis. Graphical Abstract: [Figure not available: see fulltext.]. © 2017, Springer Science+Business Media, LLC.</style></abstract><work-type><style face="normal" font="default" size="100%">Journal Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;</style></custom3><custom4><style face="normal" font="default" size="100%">2.294</style></custom4></record></records></xml>