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41.
Magnetic nanoparticle‐tethered Schiff base–palladium(II): Highly active and reusable heterogeneous catalyst for Suzuki–Miyaura cross‐coupling and reduction of nitroarenes in aqueous medium at room temperature
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K. Manjunatha Tuhin S. Koley Vishal Kandathil Ramesh B. Dateer Geetha Balakrishna B. S. Sasidhar Shivaputra A. Patil Siddappa A. Patil 《应用有机金属化学》2018,32(4)
As a continuation of our efforts to develop new heterogeneous nanomagnetic catalysts for greener reactions, we identified a Schiff base–palladium(II) complex anchored on magnetic nanoparticles (SB‐Pd@MNPs) as a highly active nanomagnetic catalyst for Suzuki–Miyaura cross‐coupling reactions between phenylboronic acid and aryl halides and for the reduction of nitroarenes using sodium borohydride in an aqueous medium at room temperature. The SB‐Pd@MNPs nanomagnetic catalyst shows notable advantages such as simplicity of operation, excellent yields, short reaction times, heterogeneous nature, easy magnetic work up and recyclability. Characterization of the synthesized SB‐Pd@MNPs nanomagnetic catalyst was performed with various physicochemical methods such as attenuated total reflectance infrared spectroscopy, UV–visible spectroscopy, inductively coupled plasma atomic emission spectroscopy, energy‐dispersive X‐ray spectroscopy, field‐emission scanning electron microscopy, transmission electron microscopy, powder X‐ray powder diffraction, thermogravimetric analysis and Brunauer–Emmett–Teller surface area analysis. 相似文献
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V. R. Patil D. D. Pawar G. U. Khapekar 《International Journal of Theoretical Physics》2012,51(7):2101-2108
In this paper, we have obtained plane symmetric cosmological models of thick domain walls with viscous field coupled with electromagnetic field in the framework of Lyra geometry, by using equation of state. Physical and geometrical implications of the models are also discussed in the presence of magnetic field. 相似文献
44.
Rapid synthesis of triarylcyanurates (2,4,6-triaryloxy-1,3,5-triazine) was carried out by reacting cyanuric chloride with the sodium salt of hydroxyaryl compounds in water using focused microwaves. Environmentally friendly procedure and isolation of pure products in excellent yields are important features of this method. 相似文献
45.
The exact solution of Einstein-Cartan field equations for static, conformally flat spherically symmetric space-time is derived
and it is proved to be Petrov-type D. 相似文献
46.
T. V. Subramanya Prasad C. R. Shahini Shivaputra A. Patil Xiaojun Huang 《Journal of Coordination Chemistry》2017,70(4):600-614
Various nitro/nitrile-functionalized benzimidazol-2-ylidene carbene complexes of silver(I) (7a–d and 11a–d) were synthesized by combination of 1-allyl/1-isopropyl/1-sec-butyl/1-isopentyl-3-(nitro/cyano-benzyl)-3H-benzimidazol-1-ium hexafluorophosphate (6a–d and 10a–d) with silver(I) oxide in acetonitrile. The compounds were characterized by 1H, 13C NMR, FT-IR, mass spectrometry, and elemental analysis. Additionally, the in vitro antibacterial activity of the N-heterocyclic carbene (NHC) precursors (6a–d and 10a–d) and their corresponding NHC-silver(I) complexes (7a–d and 11a–d) were investigated against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli using the qualitative Kirby-Bauer disk diffusion method. All the NHC-silver(I) complexes exhibited medium-to-high antibacterial activity with areas of clearance ranging from 12 mm to 21 mm, while the NHC precursors were inactive against both strains of bacteria. 相似文献
47.
Metal quinolates, Liq Alq3 Znq2 Mgq2 exhibit efficient luminescence in blue green region and find applications as emission layer in OLEDs. In most of these quinolates the excitation spectra are broad in the range 350 to 410 nm, just short of emission spectra of efficient GaN based blue LEDs. In this paper we report metal quinolates synthesized by slightly modified method in which the excitation gets extended beyond 450 nm so that there is better overlap between emission spectra of blue LED and the excitation spectra. Therefore these phosphors may be used for PC-LED applications. 相似文献
48.
Ravindra Mahadev Patil Anil A. Ghanwat Satyanarayana Ganugapati 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):114-123
Well-defined four-arm star poly(?-caprolactone)-block-poly(cyclic carbonate methacrylate) (PCL-b-PCCMA) copolymers were synthesized by combining ring-opening polymerization (ROP) with atom transfer radical polymerization (ATRP). First, a four-arm poly(?-caprolactone) (PCL) macroinitiator [(PCL-Br)4] was prepared by the ROP of ?-CL catalyzed by stannous octoate at 110°C in the presence of pentaerythritol as the tetrafunctional initiator followed by esterification with 2-bromoisobutyryl bromide. The sequential ATRP of CCMA monomer was carried out by using the (PCL-Br)4 tetrafunctional macroinitiator (MI) and in the presence of CuBr/2, 2′-bipyridyl system in DMF at 80°C with [(MI)]:[CuBr]:[bipyridyl] = 1:1:3 to yield block polymers with controlled molecular weights (Mn (NMR) = 10700 to 27300 g/mol) by varying block lengths and with moderately narrow polydispersities (Mw/Mn = 1.2–1.4). Block copolymers with different PCL: PCCMA copolymer composition such as 50:50, 70:30 and 74:26 were prepared with good yields (48-74%). All these block copolymers were well characterized by NMR, FTIR and GPC and tested their thermal properties by DSC and TGA. 相似文献
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Rupali L. Magar Prashant B. Thorat Pratima B. Thorat Vinod V. Thorat Bhagawan R. Patil Rajendra P. Pawar 《中国化学快报》2013,24(12):1070-1074
The Biginelli-type compounds 4,5,8a-triarylhexahydropyrimido[4,5-d]pyrimidine-2,7(1H,3H)-diones were synthesized by a one-pot three-component reaction using sulfated tin oxide as a reusable catalyst. This method has the advantages of high yields, short reaction time, simple starting materials and reusability of catalyst for several times. 相似文献