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61.
Arunachalam Sagadevan V. Kishore Kumar Pampana Kuo Chu Hwang 《Angewandte Chemie (International ed. in English)》2019,58(12):3838-3842
The first successful example of the three‐component coupling of N‐alkylanilines, terminal alkynes, and alcohols was achieved at room temperature by a visible‐light‐mediated copper‐catalyzed photoredox hydrogen‐atom transfer process. This method allows preparation of propargylamines through uniquely selective α‐C?H bond activation of unactivated alkylalcohols. Preliminary studies indicate that formation of α‐oxy radical is operative. This approach facilitates rapid access to biologically important propargylamines from methanol as an abundant feedstock. 相似文献
62.
Savariapichai Martin Chandran Revathi Arunachalam Dayalan 《Journal of chemical crystallography》2009,39(12):908-912
Abstract
The title complex: C4H12N2[Co(C4H7N2O2)2Cl2]2·2H2O, viz., PpH2[Co(dmgH)2Cl2]2·2H2O, where, dmgH− = dimethylglyoximate and Pp = piperazine was synthesized and analyzed by single crystal XRD studies. The complex was grown as brown crystals by the slow evaporation method in ethanol. The complex crystallizes as triclinic with the space group p[`1] p\overline{1} and unit cell parameters a = 8.4521 (10) Å, b = 10.0999 (11) Å, c = 10.8952(13) Å; α = 94.066(6)°, β = 106.047(6)° and γ = 100.901(6)°. There are two complex molecules present in the unit cell. The short intra molecular O–H···O hydrogen bonds link the glyoximate moieties in the crystal. 相似文献63.
Winaki P. Sohtun Themmila Khamrang Arunachalam Kannan Gowdhami Balakrishnan Dhandayutham Saravanan Mohammad Abdulkader Akhbarsha Marappan Velusamy Mallayan Palaniandavar 《应用有机金属化学》2020,34(5):e5593
A series of iron(III) bis-complexes of the type [FeL2]X 1-4 , X = OH− ( 1 ), Cl¯ ( 3 ), and FeCl4¯ ( 2 , 4 ), where LH is a tridentate (N,N,S) ligands such as N′-(1-pyridin-2-ylethylidene)-hydrazinecarbodithioic acid methyl ester ( HL1 ), N′-(phenylpyridin-2-ylmethylene)-hydrazinecarbodithioic acid methyl ester ( HL2 ), N′-quinolin-2-ylmethylene-hydrazinecarbodithioic acid methyl ester ( HL3 ), or N′-(1-methyl-1H-imidazol-2-yl-methylene)hydrazinecarbodithioic acid methyl ester ( HL4 ) has been isolated in moderate to good yields and completely characterized by elemental analyses, conductivity studies, and infrared and UV-visible spectral measurements. The single crystal X-ray structures of 1 , 2 and 4 revealed that two deprotonated tridentate (NNS) ligands are meridionally coordinated to constitute a distorted octahedral coordination geometry around iron(III). In acetonitrile solution, all the complexes show quasi-reversible Fe(III)/Fe(II) redox behavior. The in vitro cytotoxicity of the ligands HL1–HL4 (IC50: HL1 , 64.5; HL2 , 51.0; HL3 , 124.0; HL4 , 45.0 μM at 24 h) and complexes 1–4 (IC50: 1 , 84.5; 2 , 40.0; 3 , 168.5; 4 , 50.5 μM at 24 h) towards A549 lung cancer cell lines are similar to cisplatin (69.0 μM), revealing that free ligands cause cancer cell death with potency higher than the corresponding iron(III) complexes. Also, both the ligands and the complexes cause cell death mainly through apoptotic mode, as revealed by the observation of a higher percentage of apoptotic cells in acridine orange (AO)/ ethidium bromide (EB), and Annexin V-Cy3 stained cancer cells. 相似文献
64.
65.
C. M. Varghese A. Shunmugasundaram R. Murugesan T. Jey Abalan 《Journal of Chemical Sciences》2002,114(1):75-82
Heteropoly blues of α-1,2 and α-1,4 isomers of [PV2W10O40]5−have been prepared by using the electrochemical technique. EPR spectra, measured as a function of temperature over a wide
range (20-300 K), are explicable in terms of electron-hopping processes in heteropoly blues. Temperature dependence of A∥of
the isomers suggest that the activation energy for electron hopping is greater for the α-1,4 isomer than the α-1,2 isomer.
Other parameters like stability of the blues and intra-molecular electron transfer rate constants are also evaluated using
EPR as the tool. 相似文献
66.
Eswaran Chinnaraja Rajendran Arunachalam Jayanta Samanta Ramalingam Natarajan Palani S. Subramanian 《应用有机金属化学》2019,33(5)
The one‐pot metal templated synthesis of enantiopure binuclear Zn (II) complexes Zn2L1–Zn2L4 were obtained by treating (1R,2R)‐diphenylethylenediamine or (1S,2S)‐diphenylethylenediamine with 2‐hydroxy‐5‐methyl‐1,3‐benzenedicarboxaldehyde or 4‐tert‐butyl‐2,6‐diformylphenol and zinc acetate. The chiroptical properties of the complexes were studied by using circular dichroism spectroscopy. These ΔΔ and ΛΛ complexes were used as enantioselective catalysts for desymmetrization of meso diol to achieve monobenzoylated product with 96% yield and 88% ee. 相似文献
67.
Kumar Premnath Jayaraman Theerthagiri Jagannathan Madhavan Prabhakarn Arunachalam Mohamed A. Ghanem Abdullah M. Al-Mayouf 《Journal of Solid State Electrochemistry》2018,22(9):2641-2647
Efficient and cost-effective electrocatalysts for hydrogen evolution reaction (HER) are significant for the advancement of effective water splitting reaction. Herein, we describe the growth of cobalt molybdenum sulfide (CoMoS) at different composites of tightly packed nanocrystals, prepared by one step process of simple electrodeposition method on fluorine-doped tin oxide (FTO) substrate as highly active and low-cost HER electrocatalyst. The prepared electrocatalysts were characterized via various analytical techniques. The HER activity was evaluated through electrochemical methods such as cyclic voltammetry technique and impedance analysis. Exhaustive electrochemical examinations show that the Co0.95Mo0.05S achieved higher cathodic current density value of 14.3 mA/cm2 at η?=?250 mV with a lowest Tafel slope value towards HER. Furthermore, the active surface area of the as-deposited composite materials has been calculated by cyclic voltammetry analysis. Hence, the present work illustrates that the Co0.95Mo0.05S composite can serve as an encouraging cost-effective substitute to platinum-based electrocatalyst for HER. 相似文献
68.
Arunachalam Umamaheswaran Raja Saravanan Chelliah Selvaraj Annadevasahaya Mani Joseph Kennedy 《Czechoslovak Mathematical Journal》2022,72(3):913-925
Czechoslovak Mathematical Journal - We introduce and study the concepts of weak n-injective and weak n-flat modules in terms of super finitely presented modules whose projective dimension is at... 相似文献
69.
R. Verma J. Arunachalam S. Gangadharan 《Journal of Radioanalytical and Nuclear Chemistry》1992,164(5):327-335
A radiochemical neutron activation analysis procedure for the determination of Ta, W, Ir, Pt, Au, Cu, Cr, Co and Zn in lithium niobate has been developed. The method involves a one-step removal of radioactive nuclides of Nb, Ta and W representing the dominating radioactivity of the irradiated sample. After irradiation, the sample is fused with inactive carriers and Na2O2 in a nickel crucible. The fused cake is dissolved in HCl–H2O2 and Nb, Ta and W are homogeneously precipitated. The impurities are separated by combinations of precipitation and ion-exchange separations for precise -ray measurements with an overall chemical yield of 70% to 90%. The results are discussed. 相似文献
70.
An optimization procedure for the gallic acid-persulphate method for the ultratrace determination of vanadium is reported. The optimization step has improved the sensitivity by a factor of three. The linearity range of the calibration graph is also extended. 相似文献