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211.
1INTRoDUrnoNSomecomplexessynthesizedaccordingtotheideaof"combiningtheinorganicdistOrtedpoyhedronwithasymmetricconjugateorganicmo1ecules"areacategoryof,..promisingnonlinearopticalmaterialtl3.Thecomplexcrystalsareundoubtedlyanewimportantfieldfortheexplorationoffrequencydoublingandotherfunctionalmateri-alswhichwillbecomethefocusoftheworld'sattentiont2i.Inordertostudytherela-tionshipbetweenthestructure,synthesis,propertiesandapplicationsfurthermore,wereportthesynthesisandcrystalstructureofanewt… 相似文献
212.
A highly efficient Pd/C-catalyzed ligandless, heterogeneous Suzuki reaction of p-(un)substituted phenyl halide with (p-substituted phenyl)boronic acid in DMF/H2O solvent in a short reaction time (0.5 h) at 75 ℃ was developed. The key for such a catalytic system was the addition of 1 equivalent of tetrabutylammonium bromide. A wide variety of substituents can be tolerated and high yields of cross coupling products were achieved. The palladium catalyst can be easily recovered and reused without significantly decreasing its efficiency. 相似文献
213.
In this work, Ba(NO3)2 crystals with single crystal face were induced by using the the method of bio-mimetic mineralization and double LB films of behenic acid (BA) as the template. The crystals were characterized by Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD). The crystals were observed in regular square shape with uniform size about 5~8 μm by SEM, and they were found by XRD to grow along the (111) plane. From these experiments, we can conclude that the good selection of the (111) crystal face of Ba(NO3)2 is due to the electrostatic interactions , the match between this crystal face and the definite lattice structure of the LB films. 相似文献
214.
215.
The polymerization thermokinetics of pyrrole in the presence of iron trichloride art studied by using a Calvet microcalorimoter. The apparent activation energy, the pre-exponential constant and reaction order of this reaction in the temperature range of 25.2—37℃are 34.5 KJ·mol~(-1), 10~(2.74)S~(-1) and 1 respectively. The activation free-energies of this reaction at 25.2°, 30°and 37℃are 91.8, 92.9 and 94.2 KJ·mol~(-1) respectively. 相似文献
216.
IntroductionTherehasbeenrecentresearchinterestincrystalen gineeringandthedesignofsupramoleculararchitectures .1Byselectingthechemicalstructureofligandsandtheco ordinationgeometryoftransitionmetalions ,theorganic/inorganichybridmaterialsmayyieldaseriesofn… 相似文献
217.
N-Acyl-β-hydroxy-4-phenyl-oxazolidinethiones could be rapidly converted into their ethyl thiol esters in high yields by treatment with EtSH at 0 ℃ in CH3CN or 9 : 1 (V : V) THF-H2O in the presence of a catalytic amount of K2CO3. 相似文献
218.
219.
Xue Yuan HU Xue Sen FAN Xin Ying ZHANG Gui Rong QU Yan Zhen LI School of Chemical Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang Chongqing University of Medical Sciences Chongqing 《中国化学快报》2005,(7)
Construction of tetrahydropyran rings has attracted a great deal of interests in organic synthesis in recent years1, since tetrahydropyran moiety constitutes a structural unit in a number of natural products2. In addition, tetrahydropyran derivatives possess wide range of biological activities and pharmacological properties, such as anticancer activity3 and antihypersensitivity4. Many methods for the preparation of such compounds have already been developed5. Among them, condensation of α, β… 相似文献
220.