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Gunasekaran Balamurugan Sundarraman Balaji Rengan Ramesh Nattamai S.P. Bhuvanesh 《应用有机金属化学》2019,33(1)
A panel of six new arene Ru (II)‐NHC complexes 2a‐f , (NHC = 1,3‐diethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1a , 1,3‐dicyclohexylmethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1b and 1,3‐dibenzyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1c ) were synthesized from the transmetallation reaction of Ag‐NHC with [(η6‐arene)RuCl2]2 and characterized. The ruthenium (II)‐NHC complexes 2a‐f were developed as effective catalysts for α‐alkylation of ketones and synthesis of bioactive quinoline using primary/amino alcohols as coupling partners respectively. The reactions were performed with 0.5 mol% catalyst load in 8 h under aerobic condition and the maximum yield was up to 96%. Besides, the different alkyl wingtips on NHC and arene moieties were studied to differentiate the catalytic robustness of the complexes in the transformations. 相似文献
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Sangya Chitranshi Dr. B. Adinarayana Mainak Das Dr. Won-Young Cha Prof. Dr. Dongho Kim Prof. Dr. A. Srinivasan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(56):12911-12915
Three distinct conformational structures of carbaoctaphyrins were prepared by incorporating bis-4,4'-biphenyl units in the macrocyclic core. The free-base form adopts a figure-eight conformation, whereas the protonation triggers a conformational change with a pyrrole ring inversion and acquires an open-framework structure. The insertion of bis-RhI metal ion in the macrocyclic core affords a singly twisted conformational structure. Furthermore, the local aromaticity in the bis-4,4'-biphenyl ring dominates the overall macrocyclic aromaticity in all three forms, and thus adopts nonaromatic characteristics. These results are supported by spectral as well as theoretical studies, and they are unambiguously confirmed by X-ray crystal analyses. 相似文献
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A new solid‐phase approach for the synthesis of 2‐amido‐1,3,4‐oxadiazoles has been developed. In this synthesis, hydroxypentyl JandaJel polymer support was treated with excess of oxalyl chloride to give resin‐bound 2‐chloro‐2‐oxoacetate, and this intermediate was then coupled with different hydrazides to give resin‐bound 2‐(N′‐acylhydrazinyl)‐2‐oxoacetate. Intramolecular dehydrative cyclization of resulting resin‐bound linear precursor followed by direct amidation using aluminum amide reagent provided 5‐substituted 1,3,4‐oxadiazoles as 2‐carboxamides. To explore the scope of this reaction sequence, we synthesized a small set of library using a combination of hydrazides and amines, and the desired products were obtained in good to high yields. 相似文献
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This study evaluates the larvicidal activity of Scoparia dulcis aqueous extract against dengue vector and determines its major chemical components. The extract was tested at various concentrations ranging from 0.1 to 2 mg/mL against Aedes aegypti larvae. The extracts displayed significant larvicidal efficacy against Ae. aegypt species after 24 h exposure revealing LC50 of 3.3835 (mg/mL) and LC90 of 5.7578 (mg/mL). Finger printing profile carried out by CAMAG automatic TLC sample applicator programmed through WIN CATS software revealed peaks with different Rf values for three different volumes injected: 16, 15 and 18 peaks were spotted for 3, 6 and 9 μL, respectively. Ascending order of Rf values was also ascertained for each peak recorded. This study clearly signifies that S. dulcis extract contains numerous compounds that are known to have larvicidal properties which clearly substantiates its efficacy on Ae. aegypti larvae. 相似文献
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Rukmanikrishnan Balasubramanian Ramalingam Srinivasan Kim Sam Soo Lee Jaewoong 《Cellulose (London, England)》2021,28(9):5577-5590
Cellulose - Sustainable food packaging films were developed using a combination of k-Carrageenan (k-C), hydroxyl ethyl cellulose (HEC), silicon dioxide (SiO2), and silver (Ag) nanoparticles. The... 相似文献
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S. N. V. M. S. Gupta A. K. Nayak U. B. Misra Balaji Rao Yarasi C. Phani Babu G. Kalyanakrishnan 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(3):571-579
The present paper describes a new analytical method developed for direct determination of boron in steels using radio frequency glow discharge optical emission spectrometer. “Single parameter alternative method” technique has been used to optimize the various experimental conditions of glow discharge plasma such as forward power, gas pressure inside plasma chamber, pre-integration time, and integration time. Different emission lines for boron were studied and inter element interference effect is also discussed in the paper. A complete statistical analysis has been done to validate the developed method. A RSD of less than ±5% is achieved for boron in the range of 0.0010–0.020% in Steels using this method. 相似文献
10.
Woldemedhin M. T. Srinivasan J. Kelly R. G. 《Journal of Solid State Electrochemistry》2021,25(10):2699-2700
Journal of Solid State Electrochemistry - 相似文献