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Two 1H-2,3-dihydropyrrolizine derivatives bearing a nitro group at the 6 position have been synthesized and an improved method for nitrating pyrroles using potassium nitrate in trifluoroacetic acid was developed. An efficient, two-step synthesis of the butterfly pheromone, Danaidone, was also developed with an overall 33% yield. 相似文献
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Indra Rajasingh Albert Muthumalai R. Bharati A. S. Shanthi 《Journal of mathematical chemistry》2012,50(5):1200-1209
Molecules arranging themselves into predictable patterns on silicon chips could lead to microprocessors with much smaller circuit elements. Mathematically, assembling in predictable patterns is equivalent to packing in graphs. An H-packing of a graph G is a set of vertex disjoint subgraphs of G, each of which is isomorphic to a fixed graph H. If H is the complete graph K 2, the maximum H-packing problem becomes the familiar maximum matching problem. In this paper we give algorithms to find a perfect packing of HC(n) with P 6 and K 1,3 when n is even and thus determines their packing numbers. Further we also study the packing of HC(n) with 1, 3-dimethyl cyclohexane. 相似文献
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Shaik Firoj Basha Tangella Nagendra Prasad Veera Babu Gudise Vadiga Shanthi Kumar Naveen Mulakayala 《合成通讯》2013,43(22):3181-3190
AbstractA facile one-pot synthesis of ethyl 5-methyl-4,7-dihydrotetrazolo[1,5-a]pyrimidine, 5-tert-butyl-4,7-dihydrotetrazolo[1,5-a]pyrimidine, 6,6-dimethyl-5,6,7,9-tetrahydrotetrazolo[5,1-b]quinazolin-8(4H)-one and 5,6,7,9-tetrahydrotetrazolo[5,1-b]quinazolin-8(4H)-one derivatives were described via a three-component reaction of aldehyde, 5-aminotetrazole and diketones in PEG-400 under microwave irradiation at 110?°C for 30?min. A wide range of diketones such as ethylacetoacetate, tert-butyl acetoacetate, 5,5-dimethylcyclohexane-1,3-dione and 1,3-cyclohexanedione were utilized to carry out the synthesis of different dihydrotetrazolo[1,5-a]pyrimidines and tetrahydrotetrazolo[1,5-a]quinazolinones. This method has the advantage of green protocol, operational simplicity, high yields, recyclability of the solvent and involves isolation of the final product without column purification. The scope of this reaction tolerates with aromatic, heteroaromatic and alicyclic aldehydes. 相似文献
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Murali S Dreyer DR Valle-Vigón P Stoller MD Zhu Y Morales C Fuertes AB Bielawski CW Ruoff RS 《Physical chemistry chemical physics : PCCP》2011,13(7):2652-2655
The performance of mesoporous carbon capsules as electrode materials in electrochemical double layer capacitors (EDLCs) was evaluated in the presence of a variety of electrolytes, including room temperature ionic liquids (ILs). 相似文献
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Nelson DJ Ashworth IW Hillier IH Kyne SH Pandian S Parkinson JA Percy JM Rinaudo G Vincent MA 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(46):13087-13094
The thermodynamic effective molarities of a series of simple cycloalkenes, synthesised from α,ω-dienes by reaction with Grubbs' second generation precatalyst, have been evaluated. Effective molarities were measured from a series of small scale metathesis reactions and agreed well with empirical predictions derived from the number of rotors and the product ring strain. The use of electronic structure calculations (at the M06-L/6-311G** level of theory) was explored for predicting thermodynamic effective molarities in ring-closing metathesis. However, it was found that it was necessary to apply a correction to DFT-derived free energies to account for the entropic effects of solvation. 相似文献
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In the present work, a novel blend polymer electrolyte membrane using poly(vinyl acetate) (PVAc), poly(methyl methacrylate)
(PMMA), and lithium per chlorate (LiClO4) in different compositions has been prepared by the solution-casting technique. Their chemical, structural characters, thermal
behavior, surface morphology, and ionic conductivity were studied using Fourier transform infrared spectroscopy, X-ray diffraction,
thermogravimetric/differential thermal analyzer, scanning electron microscopy, and AC impedance analyzer, respectively. A
maximum ionic conductivity value of 1.67 × 10−4 S/cm at 303 K is obtained for PVAc–PMMA–LiClO4 complexes in the ratio of 25 × 75, keeping LiClO4 constant as 10 wt.% among all the compositions studied. 相似文献
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Hybrid solid polymer electrolyte films comprising of poly(vinyl acetate) (PVAc), poly(methyl methacrylate) (PMMA), LiClO4, and propylene carbonate are prepared by solution casting technique by varying the salt concentration. In this study, PVAc/PMMA
polymer blend ratio is fixed as 25:75 on the basis of conductivity and mechanical stability of the film. X-ray diffraction,
Fourier transform infrared impedance, thermogravimetry/differential thermal analysis and scanning electron microscopy studies
are carried out for the polymer electrolytes. The maximum ionic conductivity is found to be 4.511 × 10−4 S cm−1 at 303 K for the plasticized polymer electrolyte with 8 wt.% of LiClO4. The ionic conductivity is found to decrease with an increase of LiClO4 concentration. 相似文献