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1.
C.E. Satheesh Pushpanathan N. Sathish Kumar P. Raghavendra Kumara Ramasamy Karvembu Amar Hosamani M. Nethaji 《应用有机金属化学》2019,33(10)
Two new half‐sandwich Ru (II)(p‐cymene) complexes ( 1 and 2 ) containing dopamine‐based (N, O) Schiff base ligands ( L 1 H and L 2 H ) were synthesized and characterized by FT‐IR, UV–Visible and 1H & 13C NMR spectral techniques, and elemental analyses. The spectroscopic and analytical data revealed monobasic bidentate coordination of the ligands with Ru ion. The molecular structures of L 1 H , L 2 H and 2 were further confirmed by single crystal X‐ray diffraction study. Complexes 1 and 2 have been employed as catalysts in the transfer hydrogenation of ketones using 2‐propanol as a hydrogen source at 85 °C under base‐free condition. Good to the excellent yield of secondary alcohols, gram scale synthesis, and high TON and TOF made this catalytic system interesting. 相似文献
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Shanmugam Kotteswaran Sundaramoorthy Kannadhasan Perumalsamy Ramasamy 《Journal of Solid State Electrochemistry》2021,25(7):1949-1958
Journal of Solid State Electrochemistry - The phenyl-conjugated oligoene dye 2-cyano3-(4-diphenylaminophenyl)prop-2-enoic acid (SKS) was synthesized by chemical method, and its structure was... 相似文献
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Khadhar Navaz Umar Basha Shanthi Gnanamani Prakash Shanmugam Sujatha Venugopal Sangeetha Murthy Balagurunathan Ramasamy 《Journal of heterocyclic chemistry》2021,58(10):2000-2008
A simple and convenient method for the one-pot synthesis of 3-(1H-indole-3-carbonyl)-2H-chromen-2-one derivatives from the reaction of 3-cyanoacetyl indole and salicylaldehyde in the presence of Na2CO3 in water: methanol (1:1) is described. Wider substrate scope, high yields, operational simplicity, and simple purification process make the protocol highly applicable in the synthesis of 3-(1H-indole-3-carbonyl)-2H-chromen-2-ones. For the first time, in vitro antioxidant and antimicrobial activity was studied. Compounds 5e , 7a , and 7b exhibits good radical scavenging ability against DPPH free radical. Compounds 7b , 5f , and 5g possess lower EC50 values than the Standards AA and BHA and thus proving their high reducing power. Compounds 5d and 5f show good antibacterial activity against gram-positive bacteria (MRSA) while compounds 5c , 7a , and 7b exhibits good antibacterial activity against Bacillus sp. Compounds 5b and 5e show good antibacterial activity against gram negative bacterial strains (Escherichia coli, Klebsiella pneumoniae) and compounds 5g and 5h exhibits good antifungal activity against Candida albicans. 相似文献
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Muniyappan Boominathan Jeyavelraman Kiruthika Murugan Arunachalam 《Journal of polymer science. Part A, Polymer chemistry》2019,57(14):1508-1515
A pillar[5]arene pendant polymer (Poly‐P[5]A) is synthesized via ROMP using Grubb's first‐generation catalyst. GPC analysis of the polymer suggested ~30 pendant pillar[5]arene units in the polymer. Supramolecular polypseudorotaxane assembly is constructed by intermolecularly crosslinking pendant pillar[5]arene units using a bispyridinium guest via host–guest complexation. Formation of the polypseudorotaxane assembly is characterized by 1D/2D NMR techniques and DLS analysis. Moreover, anion‐responsiveness of the polypseudorotaxane assembly is demonstrated by 1H NMR spectroscopic analysis using chloride anion as external stimulus. Scanning electron microscopic analysis of the poly‐P[5]A showed breath‐figure assembly and upon crosslinking with G.2PF6 the polymer self‐assemble to give a supramolecular polymer network. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1508–1515 相似文献
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Dr. Siva Senthil Kumar Boominathan Kai-Hsin Chang Dr. Yu-Chiao Liu Chi-Shin Wang Cheng-Feng Wu Dr. Ming-Hsi Chiang Prof. Pi-Tai Chou Prof. Yao-Ting Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(30):7280-7284
Diindeno-fused dibenzo[a,h]anthracene 6 and diindeno-fused dibenzo[c,l]chrysene 9 contain the key moieties 1,4-quinodipropene (1,4-QDP) and 2,6-naphthoquinodipropene (2,6-NQDP), respectively, and they both have an open-shell singlet ground state. The latter compound exhibits a strong biradical character and interesting properties, including a low ΔET−S (2.44 kcal mol−1), a small HOMO–LUMO gap (1.06 eV), a wide photoabsorption range (250–1172 nm), and a large two-photon absorption cross-section (σ=1342±56 GM). This work verifies that 6 has a slightly larger HOMO–LUMO gap and ΔET−S than its helical isomer diindeno[2,1-f:1′,2′-j]picene (DIP), but is a much stronger two-photon absorber, verifying the important effect of geometry on the photophysical properties. 相似文献
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