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1.
Nano palladium supported on high‐surface‐area metal–organic framework MIL‐101: an efficient catalyst for Sonogashira coupling of aryl and heteroaryl bromides with alkynes
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Manne Annapurna T. Parsharamulu P. Vishnuvardhan Reddy M. Suresh Pravin R. Likhar Mannepalli Lakshmi Kantam 《应用有机金属化学》2015,29(4):234-239
Palladium nanoparticle‐incorporated metal–organic framework MIL‐101 (Pd/MIL‐101) was successfully synthesized and characterized using X‐ray diffraction, nitrogen physisorption, X‐ray photoelectron, UV–visible and infrared spectroscopies, and transmission electron microscopy. The characterization techniques confirmed high porosity and high surface area of MIL‐101 and high stability of nano‐size palladium particles. Pd/MIL‐101 nanocomposite was investigated for the Sonogashira cross‐coupling reaction of aryl and heteroaryl bromides with various alkynes under copper‐free conditions. The reusability of the catalyst was tested for up to four cycles without any significant loss in catalytic activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
2.
Selvaraj Vishnuprasad Morri Bindusai Nair Lakshmi M. Krishnan Haribabu 《Journal of Thermal Analysis and Calorimetry》2019,137(5):1527-1536
Journal of Thermal Analysis and Calorimetry - Low thermal conductivity is a primary issue in the development of efficient heat transfer fluids and materials required for the thermal management of... 相似文献
3.
2-Formyl glycals undergo rapid condensation with arylhydrazines under solvent-free conditions to give the corresponding optically pure 4-substituted pyrazoles in good yields with high selectivity. The stereochemistry of the products was assigned by various NMR experiments. 相似文献
4.
Friedel-Crafts alkylation of indoles with epoxides to afford 3-alkyl indole derivatives at room temperature with moderate to good yields and high regioselectivity using nanocrystalline titanium(IV) oxide catalyst is described. 相似文献
5.
Starting from cyclohexanecarboxylic acid, a combination of an Ireland ester Claisen rearrangement and RCM reactions was exploited for an efficient construction of spiro[5.5]undecanes containing a quaternary carbon atom adjacent to the spirocentre and the methodology was extended to complete total syntheses of three chamigrenes. 相似文献
6.
Cerium(IV) ammonium nitrate in substoichiometric amounts, promotes the intramolecular cyclization of epoxypropyl cinnamyl ethers to the corresponding 3,4,5-trisubstituted tetrahydropyran derivatives in moderate to good yields. 相似文献
7.
A. Lakshmi Sailaja K. Kishore Kumar D. V. R. Ravi Kumar C. Mohan Kumar N. M. Yugandhar G. Srinubabu 《Chromatographia》2007,65(5-6):359-361
A simple, rapid, and sensitive high-performance liquid chromatographic method for estimation of efavirenz in human plasma
has been developed and validated. Chromatography was performed with C18 analytical column and 50:50 acetonitrile–phosphate buffer (pH 3.5) as mobile phase. Compounds were monitored by UV detection
at 247 nm. The retention time for efavirenz was 6.45 min and that for the internal standard, nelfinavir, was 2.042 min. Response
was a linear over the concentration range of 0.1 μg–10 μg mL−1 in human plasma. The method was simple, specific, precise and accurate and was useful for bioequivalence and pharmacokinetic
studies of efavirenz. 相似文献
8.
G.V.M. Sharma J. Janardhan Reddy P. Sree Lakshmi Palakodety Radha Krishna 《Tetrahedron letters》2004,45(41):7729-7732
A practical and efficient electrophilic substitution reaction of indoles with a variety of aldehydes was carried out using catalytic trichloro-1,3,5-triazine (10 mol %) in acetonitrile to furnish the corresponding bis(indolyl)methanes in excellent yields. Similarly, sugar derived aldehydes gave hitherto unknown bis(indolyl)glycoconjugates in very good yields. 相似文献
9.
Efficient total syntheses of the herbertane sesquiterpene title compounds have been accomplished employing an Ireland ester Claisen rearrangement and ring-closing metathesis reaction sequence based strategy for the construction of two stereogenic vicinal quaternary carbon atoms on a cyclopentane. 相似文献
10.
Tada M Taniike T Kantam LM Iwasawa Y 《Chemical communications (Cambridge, England)》2004,(22):2542-2543
The self-dimerized chiral assembly of vanadium-Schiff-base complexes was found to occur on a SiO2 surface and to be the first heterogeneous catalyst for the asymmetric oxidative coupling of 2-naphthol with 100% selectivity and 90% enantioselectivity. 相似文献