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351.
Priyanka L. Anandgaonker Sunita Jadhav Suresh T. Gaikwad Anjali S. Rajbhoj 《Journal of Cluster Science》2014,25(2):483-493
An electrochemical reduction method was used for the preparation of TiO2 nanoparticles in which agglomeration with formation of undesired metal powders is prevented by the presence of ammonium stabilizers. These synthesized nanoparticles were characterized by UV–Visible, XRD, SEM–EDS and TEM analysis techniques. These synthesized nanoparticles of TiO2 were tested as heterogeneous catalyst for the synthesis of tetrahydrobenzo[b]pyran derivative using three components reaction of aromatic aldehyde, dimedione and malononitrile by simply stirring at room temperature in a solvent free condition. 相似文献
352.
Maddali L.N. Rao Varadhachari Venkatesh Deepak N. Jadhav 《Journal of organometallic chemistry》2008,693(15):2494-2498
An atom-efficient cross-coupling reactivity of triarylbismuths (1 equiv) was demonstrated by cross-coupling reaction with 3 equiv of α,β-unsaturated acyl chlorides under palladium catalysis in the synthesis of a series of functionalized α, β-unsaturated ketones in high isolated yields. 相似文献
353.
Jadhav VH Jang SH Jeong HJ Lim ST Sohn MH Kim JY Lee S Lee JW Song CE Kim DW 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(13):3918-3924
Herein, we report the promising use of n-oligoethylene glycols (oligoEGs) as mutifunctional promoters for nucleophilic-substitution reactions employing alkali metal salts. Among the various oligoEGs tested, pentaethylene glycol (pentaEG) had the most efficient catalytic activity. In particular, when compared with other nucleophiles examined, a fluorine nucleophile generated from CsF was significantly activated by the pentaEG promoter. We also performed various facile nucleophilic-displacement reactions, such as the halogenation, acetoxylation, thioacetoxylation, nitrilation, and azidation of various substrates with potassium halides, acetate, thioacetate, cyanide, and sodium azide, respectively, in the presence of the pentaEG promoter. All of these reactions provided their desired products in excellent yields. Furthermore, the combination of pentaEG and a tert-alcohol medium showed tremendous efficiency in the nucleophilic-displacement reactions (fluorination and methoxylation) of base-sensitive substrates with basic nucleophiles (cesium fluoride and potassium methoxide, respectively). The catalytic role of oligoEGs was examined by quantum-chemical methods. The oxygen atoms in oligoEGs were found to act as Lewis bases on the metal cations to produce the "flexible" nucleophile, whereas the two terminal hydroxy (OH) groups acted as "anchors" to orientate the nucleophile and the substrate into an ideal configuration for the reaction. 相似文献
354.
Bandyopadhyay A Jadhav SV Gopi HN 《Chemical communications (Cambridge, England)》2012,48(57):7170-7172
Synthesis, crystal conformations of α/γ(4)-hybrid peptide helices containing proteinogenic amino acid side-chains, and the analogy with the α-helix are reported. Results suggest that α/γ(4)-hybrid peptides adopted helical conformations with 12-membered H-bond pseudocycles in single crystals. 相似文献
355.
V.A. Shelke S.M. Jadhav V.R. Patharkar S.G. Shankarwar A.S. Munde T.K. Chondhekar 《Arabian Journal of Chemistry》2012,5(4):501-507
The solid complexes of La(III), Ce(III), Pr(III), Nd(III), Sm(III) and Gd(III) with 4-hydroxy-3-(1-{2-(2-hydroxy-benzylidene)-aminophenylimino}-thyl)-6-methy-pyran-2-one (H2L) derived from o-phenylenediamine, 3-acetyl-6-methyl-(2H)pyran,2,4(3H)-dione (dehydroacetic acid or DHA) and salicylic aldehyde have been synthesized and characterized by elemental analysis, conductometry, magnetic susceptibility, UV–visible, FTIR, 1H NMR spectra, X-ray diffraction, and thermal analysis and screened for antimicrobial activity. The FTIR spectral data suggest that the ligand behaves as a dibasic tetradentate ligand with ONNO donar atoms sequence towards central metal ion. From the microanalytical data, the stoichiometry of the complexes has been found to be 1:1 (metal:ligand). The physico-chemical data suggest distorted octahedral geometry for La(III), Ce(III), Pr(III), Nd(III), Sm(III) and Gd(III) complexes. The X-ray diffraction data suggest monoclinic crystal system for La(III) and Ce(III) and orthorhombic crystal system for Pr(III) and Nd(III) complexes. Thermal behaviour (TGA/DTA) of the complexes was studied and kinetic parameters were determined by Horowitz–Metzger and Coats–Redfern methods. The ligand and their metal complexes were screened for antibacterial activity against Staphylococcus aureus, Escherichia coli and Bacillus sp. Fungicidal activity against Aspergillus niger, Trichoderma and Fusarium oxysporum. 相似文献
356.
Sushilkumar A. Jadhav 《Central European Journal of Chemistry》2012,10(5):1640-1646
Two new long-chain carboxylic acids (1, 2) bearing strong fluorescent group pyrene as ligands for Self-Assembled Monolayers (SAMs) have been synthesized. The multistep targeted synthesis is accomplished by use of Pyren-1-yl methylamine hydrochloride and employing simplified synthetic protocols. Compound 2 contains a chiral center purposely introduced along the atom chain in order to make it suitable for chiro-optical studies of the resulting SAMs. 相似文献
357.
A new facile amphiphile cholestane-based zinc complex 4 containing a 3-aminopropylimidazole moiety at the 3α and 7α positions of cholestane was designed and synthesized. Recognition selectivity of the new receptor 4 with various anions was assessed by 1H NMR titration. Dihydrogen phosphate showed the highest binding affinity among all the tested anions (Ka = 4.4 × 105 M?1). 相似文献
358.
Nagi Reddy P Ramesh V Srinivas R Sharma GV Jayaprakash P Jadhav VB Nagendar P 《Journal of mass spectrometry : JMS》2006,41(8):1105-1108
359.
Jyoti Ramesh Jadhav 《Tetrahedron letters》2010,51(45):5954-5958
A new facial amphiphile cholestane-based receptor 1 containing a 2-imidazolylethylamino moiety at the 3α and 7α positions of cholestane was synthesized. Recognition selectivity of the new receptor 1 with various dicarboxylic acids was assessed by 1H NMR titration. Maleic acid showed the highest binding constant among all the tested acids (Ka = 9.36 × 104 M−1). 相似文献
360.
Anil Disale Chittaranjan Nayak Nagesh Suryawanshi Nitin Jadhav Umesh Jagdale Gunwant Kate Sunil Thakare Shri Prakash Pandey Prakhakar Sharma Amit Saxena 《Macromolecular Symposia》2024,413(1):2300009
Industrial waste locks are used as raw materials to reduce harmful effects on the environment and improve environmental performance. Marble clay powder can be used as a filling aid and can fill voids in concrete structures. This article will show you how to use a maximum natural sand alternative in concrete with marble powder and quarry dust. The challenge of the 21st century is to change to a new form that can support the natural system. This necessitates a radical rethinking of how to give the community infrastructure and housing. Making a concerted effort to develop novel, innovative, and alternative construction materials may be necessary. Jungles of concrete around cause's impact on the Environment and it would result in climate change. Mankind must avoid the use of things that are detrimental to the environment. So in this paper, it is decided to address the issue by adopting the use of the green concrete concept which is environmentally friendly. Green concrete is concrete made up using industrial wastes such as marble powder, quarry dust, wood ash, paper pulp, etc. Green concrete, which is capable of sustainable development, helps to reduce the consumption of natural resources, energy use, and environmental pollution. Green concrete is more cost-effective than ordinary concrete and reduces the cost of resultant concrete by 14%–20%. It is also observed that the alkali-aggregate reaction and sulfate attack resistance of concrete are both significantly improved. Green concrete is a useful tool for lowering environmental pollution and enhancing concrete's resistance to harsh conditions. All stages of infrastructure construction and rehabilitation will follow this trend of using new cement and techniques. Green concrete's adaptability and its performance derivatives will meet a variety of future needs. 相似文献