01655nas a2200181   4500008004100000022001400041245009200055210006900147260007100216300001400287490000700301520095700308100002101265700002201286700002201308700002201330856012101352       2013                        eng d  a1083-616000aContinuous flow multipoint dosing approach for selectivity engineering in sulfoxidation0 aContinuous flow multipoint dosing approach for selectivity engin  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcOCT  a1293-12990 v173 a<p>A continuous synthesis approach with multipoint dosing of one of the reagents is demonstrated for the synthesis of sulfoxide compounds such as proton pump inhibitors. Use of multipoint dosing of the oxidizing agent helped to minimize the possibility of over-oxidation leading to sulfone. Different oxidizing agents were used, and the effect of various parameters (viz. mole ratio of sulfide to oxidizing agent, temperature, residence time, concentration of oxidizing agent, etc.) on the yield of the desired sulfoxide compound was studied. Single-point and multipoint dosing approaches of the oxidizing agent were used for the most promising set of parameters. The performance was compared in terms of conversion of sulfide and the selectivity of the desired sulfoxide. Numbering up approach was used to produce the sulfoxide in a relatively large quantity at laboratory scale with complete conversion and over 99% selectivity for the sulfoxide.</p>1 aKulkarni, A., A.1 aNivangune, N., T.1 aJoshi, Rohini, R.1 aJoshi, Ramesh, A.  uhttp://library.ncl.res.in/content/continuous-flow-multipoint-dosing-approach-selectivity-engineering-sulfoxidation-001998nas a2200205   4500008004100000245016600041210006900207260000800276300001500284490000800299520118800307653002301495653002301518653003801541653002401579100002201603700001901625700001901644856012901663       2017                        eng d00aMgFeCe ternary layered double hydroxide as highly efficient and recyclable heterogeneous base catalyst for synthesis of dimethyl carbonate by transesterification0 aMgFeCe ternary layered double hydroxide as highly efficient and   cOCT  a 2558-25690 v1473 aA 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.10aDimethyl carbonate10aethylene carbonate10aMg–Fe–Ce Ternary Hydrotalcite10atransesterification1 aNivangune, N., T.1 aRanade, V., V.1 aKelkar, A., A.  uhttp://library.ncl.res.in/content/mgfece-ternary-layered-double-hydroxide-highly-efficient-and-recyclable-heterogeneous-base