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Research on Chemical Intermediates - The rapid method for the synthesis of organic azides was achieved by employing azide acceptors such as halides, epoxides and pseudohalides like diazonium salts... 相似文献
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Design and synthesis of five new derivatives of benzophenone based imidazole dyes is presented. Synthesized dyes were well characterized by 1H NMR, 13C NMR, FT-IR and mass analysis. Dyes contain a secondary acceptor, ESIPT core and different donors forming (D-ESIPT core-A) as basic skeleton in order to study both ESIPT and ICT systematically in this same class of dyes. Dyes without a donor substituent showed ESIPT emission while dyes with a substituted strong donor showed intramolecular charge transfer (ICT) emission. Moreover emission properties of methoxy analogue dyes has been studied to further confirm non-ESIPT emission in dyes without donors and ICT emission in strong donor substituted dyes. All dyes exhibited long range emissions from 392 to 567 nm. Dyes exhibiting ESIPT emission showed negative solvatochromism while ICT emission exhibiting dyes shows positive solvatochromism. ICT and ESIPT characteristics are well correlated with polarity functions plots and Mulliken–Hush analysis. Experimental observations are well supported by TD–DFT and computed energies. The electrophilicity index has been calculated to get details of the stabilities of possible tautomers. 相似文献
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Sachin V. Bhilare Nitin B. Darvatkar Amol R. Deorukhkar Meghana S. Rasalkar 《合成通讯》2013,43(18):3111-3117
1‐Butyl‐3‐methylimidazolium chloroaluminate, [bmim]Cl·.AlCl3 (molar fraction, N=0.67), ionic liquid has been used in combination with metallic Zn for the reductive coupling of carbonyl compounds to synthesize symmetrical olefins, with the Z‐isomer formed predominantly. The ionic liquid played a dual role of Lewis acid catalyst and solvent. 相似文献
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Amol D. Shinde R. Acharya R. Verma A. V. R. Reddy 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(3):409-412
Nuclear and commercial grade graphite samples were analysed by instrumental neutron activation analysis (INAA) using high flux reactor neutrons. Eleven elements (Na, K, As, Sc, Fe, Cr, Co, Zn, La, Ce, and Sm) were determined in eight samples of graphite (two nuclear grade and six commercial grade) by irradiating at a neutron flux of 3?×?1013 cm?2 s?1 in CIRUS reactor and assaying the activity by high-resolution gamma ray spectrometry using 40% relative efficiency HPGe detector coupled to an MCA. Concentrations of elements were determined by relative method of INAA. Results of both types of graphites as well as detection limits achieved by INAA method are discussed in the paper. 相似文献
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Amol A. Thorave Pinkal N. Prajapati Jignesh P. Pethani Krunal C. Kothari Mukul R. Jain Pankaj R. Patel Rajendra K. Kharul 《Tetrahedron letters》2009,50(40):5660-5663
Convenient synthesis of 4-substituted 2-aminothiazolo[4,5-d]pyridazinones has been achieved in 12 steps with overall yield of 19% by employing Grignard reaction as the key step. The route utilizes well established thiazole ring formation followed by Grignard reaction to introduce substitution at 4-position effectively. In addition to the use of inexpensive chemicals, the present route first time gave access to the 4-substituted 2-aminothiazolo [4,5-d]pyridazinones with free amino group at C-2 position. 相似文献
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Fission product yield studies in the reaction of 99.2 MeV 19F with 209Bi have been carried out for the first time using gamma-ray spectrometry. The cross sections for the production of fission
products have been determined. The yield distribution of fission products was found to be symmetric and broad with FWHM around
22 mass units and peak near mass 111. The average number of neutrons emitted per fission has been found to be around 6.7.
The comparison of the fission products yield distribution of 209Bi using projectiles like 4He, 12C, 16O, and 19F have shown that the mass of symmetric peak increases as the mass of the compound nucleus increases. The high fission yield
around mass 112 has been attributed to the presence of deformed neutron shells. The total fission cross section and width
of the mass distribution have been found to be low in case of 16O induced fission as compared to the 4He, 12C, and 19F induced fission of 209Bi. 相似文献