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1.
Ai Suzuki Parasuraman Selvam Tomonori Kusagaya Seiichi Takami Momoji Kubo Akira Imamura Akira Miyamoto 《International journal of quantum chemistry》2005,102(3):318-327
The decomposition reaction dynamics of 2,3,4,4′,5‐penta‐chlorinated biphenyl (2,3,4,4′,5‐PeCB), 3,3′,4,4′,5‐penta‐chlorinated biphenyl (3,3′,4,4′,5‐PeCB), and 2,3,7,8‐tetra‐chlorinated dibenzo‐p‐dioxin (2,3,7,8‐TCDD) was clarified for the first time at atomic and electronic levels, using our novel tight‐binding quantum chemical molecular dynamics method with first‐principles parameterization. The calculation speed of our new method is over 5000 times faster than that of the conventional first‐principles molecular dynamics method. We confirmed that the structure, energy, and electronic states of the above molecules calculated by our new method are quantitatively consistent with those by first‐principles calculations. After the confirmation of our methodology, we investigated the decomposition reaction dynamics of the above molecules and the calculated dynamic behaviors indicate that the oxidation of the 2,3,4,4′,5‐PeCB, 3,3′,4,4′,5‐PeCB, and 2,3,7,8‐TCDD proceeds through an epoxide intermediate, which is in good agreement with the previous experimental reports and consistent with our static density functional theory calculations. These results proved that our new tight‐binding quantum chemical molecular dynamics method with first‐principles parameterization is an effective tool to clarify the chemical reaction dynamics at reaction temperatures. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献
2.
Pal M Batchu VR Parasuraman K Yeleswarapu KR 《The Journal of organic chemistry》2003,68(17):6806-6809
We herein report the efficient syntheses of 4-(hetero)aryl-substituted 1-chlorophthalazines via heteroarylation of arenes/heteroarenes through AlCl(3)-induced C[bond]C formation reactions. A number of (hetero)arenes were reacted with 1,4-dichlorophthalazine to give aryl/heteroaryl-substituted phthalazines in good to excellent yields. Many of them were converted to the corresponding phthalazin-1(2H)-ones. 相似文献
3.
Karuppasamy Kohila Rani Rajkumar Devasenathipathy Jia-Zheng Wang Xiao-Yuan Hui Jian-De Lin Yi-Miao Zhang Liu-Bin Zhao Jian-Zhang Zhou De-Yin Wu Zhong-Qun Tian 《Current Opinion in Electrochemistry》2022
Plasmonic noble metal nanostructures have been targeted due to their strong surface plasmon resonance at photoelectrochemical interfaces. Recently, it has been concluded that, the plasmonic noble metal nanostructures on photoexcitation permit the transfer of effective hot carriers (hot electron/hole pair) to nearby adsorbed molecules where, the transformed hot carriers can efficiently decrease the activation barrier of a reaction. In this review, our recent achievements in the plasmon-mediated chemical reactions of organic molecules such as para-aminothiophenol, substituted para-aminothiophenol and para-nitrothiophenol at nanostructures modified noble metal electrodes using surface enhanced Raman spectroscopy, electrochemical methods, and theoretical calculations will be discussed. 相似文献
4.
Kohila rani?Karuppasamy Rajkumar?DevasenathipathyEmail author Sea-Fue?WangEmail author 《Mikrochimica acta》2017,184(8):2569-2577
The authors describe an electrochemical approach for the preparation of a glassy carbon electrode (GCE) modified with graphene oxide and silver nanodentrites (AgNDs). The coating was obtained by using an aqueous solution containing silver nitrate, phosphate and ammonia. The phosphate anions act as a scaffold for the improved deposition of AgNDs. The effects of deposition potential and time and concentration of electrolyte on the formation of the AgNDs were optimized. The modified GCE displays good electrocatalytic activity towards the oxidation of dissolved hydrazine. The electron transfer coefficient and diffusion coefficient are 0.60 and 4.64 × 10?5 cm2 s?1 respectively. The electrode exhibits a linear response over the 100 nM to 670 μM hydrazine concentration range and a detection limit (LOD) of 33 nM. The sensitivity of the modified electrode is 2077 μA mM?1 cm?2 at a typical working voltage of 0.1 V (vs Ag/AgCl). This LOD is much lower than that of the allowable concentration of hydrazine in drinking water as defined by the US EPA and the WHO. 相似文献
5.
Enzyme from Daucus carota root catalyzed Henry reaction of substituted benzaldehydes and nitromethane in phosphate buffer of pH 7 at 28?°C to afford β-nitroalcohols in excellent yields (up to 94%). 相似文献
6.
Dey S Pal C Nandi D Giri VS Zaidlewicz M Krzeminski M Smentek L Hess BA Gawronski J Kwit M Babu NJ Nangia A Jaisankar P 《Organic letters》2008,10(7):1373-1376
3,3'-Bipyrroles 3 could be synthesized using a double Michael addition reaction involving diaroyl acetylene 1 and the appropriate 1,3-dicarbonyls 2 using ammonium acetate as a nitrogen source. The axial chirality of bipyrrole was anticipated from the X-ray crystal structure and DFT calculations and confirmed by separating the racemates on a chiral column and subsequent CD spectra of the enantiomers. The absolute configuration of the enantiomers was achieved by theoretical CD spectra calculation using the ZINDO method. 相似文献
7.
Karuppasamy B. Shenbagabalakrishnan B. Gayathri V. 《Journal of Solid State Electrochemistry》2023,27(4):1001-1009
Journal of Solid State Electrochemistry - Graphite nanosheets (G_NS)-coated FTO thin film is taken as counter electrode. Normally, precious metal like platinum (Pt) is considered as counter... 相似文献
8.
Ashok K. Varma Ashwini Nangia Gautam R. Desiraju Venkatachalam S. Giri Parasuraman Jaisankar 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(1):97-99
3-Acetyl-1,6,7,12b-tetrahydroindolo[2,3-a]quinolizin-2(12H)-one, C17H16N2O2, consists of two symmetry-independent molecules and each forms a layered structure stabilized by N—H⃛O and C—H⃛O hydrogen bonds. In 3-acetyl-6,7-dihydroindolo[2,3-a]quinolizin-4(12H)-one monohydrate, C17H14N2O2·H2O, the structure is stabilized by O—H⃛O, N—H⃛O and C—H⃛O hydrogen bonds, with the ordered water molecule playing a crucial role in the self-assembly. Contribution from the weak interactions to the strong hydrogen-bonded network is a common feature in both structures. 相似文献
9.
Synthesis of Small‐Sized,Porous, and Low‐Toxic Magnetite Nanoparticles by Thin POSS Silica Coating 下载免费PDF全文
Dr. Swee Kuan Yen D. Prathyusha Varma Wei Mei Guo Dr. Vincent H. B. Ho Dr. Vimalan Vijayaragavan Dr. Parasuraman Padmanabhan Prof. Kishore Bhakoo Prof. Subramanian Tamil Selvan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):3914-3918
In this communication, we report the synthesis of small‐sized (<10 nm), water‐soluble, magnetic nanoparticles (MNPs) coated with polyhedral oligomeric silsesquioxanes (POSS), which contain either polyethylene glycol (PEG) or octa(tetramethylammonium) (OctaTMA) as functional groups. The POSS‐coated MNPs exhibit superparamagnetic behavior with saturation magnetic moments (51–53 emu g?1) comparable to silica‐coated MNPs. They also provide good colloidal stability at different pH and salt concentrations, and low cytotoxicity to MCF‐7 human breast epithelial cells. The relaxivity data and magnetic resonance (MR) phantom images demonstrate the potential application of these MNPs in bioimaging. 相似文献
10.
Manojit Pal Venkataraman SubramanianKaruppasamy Parasuraman Koteswar Rao Yeleswarapu 《Tetrahedron》2003,59(48):9563-9570
(S)-Prolinol facilitated the coupling reaction of terminal alkynes with 3-iodoflavone under palladium-copper catalysis in aqueous DMF affording a mild and convenient method for the synthesis of 3-alkynyl substituted flavones of potential biological interest. 相似文献