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CuI/Proline-catalyzed N-Arylation of Nitrogen Heterocycles

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Chinese Chemical Letters 2006年第3期17卷 313-316页

作者： Wei DENG Ye Feng WANG Chen ZHANG lei LIU Qing xiang guo Department of Chemistry University of Science and Technology of China Hefei 230026

Ma＇s CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. With this new reaction condition the cross coupling with aryl iodides could be accomplished in 1,4-dioxane instead of DMSO. This reactin also could be carried out in DMF. Furthermore, the coupling yields under the new conditions are usually higher than in Ma＇s original methods.

关键词： Cross coupling reaction CuI N-arylation nitrogen heterocycle proline.

CuI-catalyzed Synthesis of Aryl Thiocyanates from Aryl Iodides

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Chinese Chemical Letters 2006年第10期17卷 1283-1286页

作者： Ye Feng WANG Yuan ZHOU Jia Rui WANG lei LIU Qing xiang guo Department of Chemistry University of Science and Technology of China Hefei 230026

An operationally simple and inexpensive catalyst system was developed for the cross coupling of potassium thiocyanate with aryl iodides by using CuI as catalyst, 1, 10-phenanthroline as ligand, and tetraethylammonium iodide as activator. The procedure is applicable for the synthesis of diverse aryl thiocyanates without any exotic, poisonous reagents.

关键词： Cross coupling reaction CuI aryl thiocyanate,Aryl Iodide 1 10-phenanthroline.

Copper-mediated synthesis of N,N'-diarylhydrazines from boronic acids

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Chinese Chemical Letters 2007年第5期18卷 499-501页

作者： Ye Feng Wang Yuan Zhou Jia Rui Wang lei Liu Qing xiang guo Department of Chemistry University of Science and Technology of China Hefei 230026 China

N,N＇-Diarylhydrazines have been prepared via the reaction of N-Boc-aryl hydrazines with boronic acids mediated by copper acetate. This mild reaction condition tolerates the presence of a variety of functional groups.

关键词： Cross coupling reaction N,N'-Diarylhydrazines Boronic acids Copper acetate

Signature Inversion of Yrast Band in Odd-Odd ^(162)Lu Nucleus

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Chinese Physics Letters 1996年第4期13卷 257-260页

作者： ZHANG Yu-hu ZHOU Xiao-hong ZHAO Qing-zhong SUN xiang-fu lei xiang-guo guo Ying-xiang LIU Zhong CHEN Xing-feng ZHU Yong-tai WEN Shu-xian YUAN Guan-jun LIU xiang-an Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Institute of Atomic Energy Beijing 102413

High spin states of the odd-odd ^(162)Lu nucleus have been studied via ^(147)Sm(^(19)F,4nγ)reaction at 95MeV beam *** scheme for yrast band based on π[h_(11/2)]v[i_(13/2)]quasiparticle configuration was established up to I^(π)-(23^(-))for the first *** band shows the signature inversion in energy before backbending generally appeared in this mass *** is stressed that the signature splitting in 162Lu is larger than that in 160 Tm nucleus.

关键词： energy signature

A High-Spin Isomer in ^(198)Bi

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Chinese Physics Letters 1996年第8期13卷 576-578页

作者： ZHOU Xiao-hong SUN xiang-fu guo Ying-xiang lei xiang-guo CHEN Xin-feng LIU Zhong ZHANG Yu-hu JIN Han-juan LUO Yi-xiao WEN Shu-xian YUAN Guan-jun LI Guang-sheng YANG Chun-xiang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China Institute of Atomic Energy Beijing 102413

High-spin states in ^(198)Bi were populated via the ^(187)Re(^(16)O,5n)reaction.A partial level scheme for ^(198)Bi was established for the first time,including a 15^(+)high-spin isomeric state with a measured half-life of 8.0±*** comparing the level structure of ^(198)Bi with that of the even-even core ^(198)Pb,the configuration v(i_(13/2))^(-2) v(P_(3/2))^(-1)π(h_(9/2))^(1) was ascribed to this isomeric state.

关键词： reaction state

New Isomeric States in ^(197)Bi

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Chinese Physics Letters 1996年第1期13卷 13-16页

作者： ZHOU Xiao-hong SUN xiang-fu guo Ying-xiang lei xiang-guo CHEN Xin-feng LIU Zhong ZHANG Yu-hu JIN Han-juan LUO Yi-xiao WEN Shu-xian YUAN Guan-jun LI Guang-sheng YANG Chun-xiang Institute of Modern Physics Academia SinicaLanzhou 730000 China Institute of Atomic Energy Beijing 102413

The high-spin states in ^(197)Bi have been studied with the ^(187)Re(^(16)O,6n)reaction at ^(16)O energies from 85 to ***-beam measurements of γ-ray excitation functions,γ-γ-t coincidences and γ-ray angular distributions were carried out with six BGO(AC)HPGe detectors and one intrinsic Ge planar *** new tram sitions and three new isomers were observed,and a level scheme for ^(197)Bi was *** differences between the present work and the previous results were found.

关键词： detector isomers

Evidence for Octupole Correlations in ^(117)Xe

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Chinese Physics Letters 1996年第11期13卷 805-808页

作者： LIU Zhong SUN xiang-fu ZHOU Xiao-hong lei xiang-guo guo Ying-xiang JIN Han-juan ZHANG Yu-hu CHEN Xin-feng LUO Yi-xiao WEN Shu-xian YANG Chun-xiang YUAN Guan-jun LI Guang-sheng LIU xiang-an Chen Yong-shou Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China Institute of Atomic Energy Beijing 102413

High spin states in neutron-deficient ^(117)Xe have been studied by using in-beamγspectroscopy method.A new positive-parity rotational band has been *** decays into the yrast vh_(11/2 )band via five electric dipole *** magnitudes of these E1 transitions are extracted and they are much enhanced compared to the normal E1 *** is taken as an evidence for octupole correlations in ^(117)Xe.

关键词： method transitions

Properties of theβDelayed Proton Decay of 147Er

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Chinese Physics Letters 2010年第6期27卷 59-61页

作者： MA Fei ZHOU Xiao-Hong ZHENG Yong XU Shu-Wei XIE Yuan-xiang CHEN Liang ZHANG Yu-Hu LI Zhan-Kui QIANG Yun-Hua lei xiang-guo guo Ying-xiang guo Song DING Bing WANG Hai-Xia LI Guang-Shun ZHOU Hou-Bing Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 Graduate University of Chinese Academy of Sciences Beijing 100049

The β-delayed proton decay of 147Er is studied experimentally using the 58 Ni＋92Mo reaction at a beam energy of 383 MeV. Based on a He-jet apparatus coupled with a tape transport system, the β-delayed proton radioactivities both from the vδl/2 ground state and the vh11/2 isomer in 147 Er are identified by proton-7 coincidence measurements. By analyzing the time distribution of the 4＋ → 2＋-γ transition in the grand-daughter nucleus 146Dy, a half-life of 1.6 ± 0.2s is determined for the Vh11/2 isomer in 147 Er. The half-life for the ground state of 147Er is estimated to be 3.2±1.2 s.

关键词： Tapes Transport Measurement

Effects of Bases on the Stabilities of Nucleoside C4'Radicals

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Chinese Chemical Letters 2003年第10期14卷 1073-1076页

作者： Bo Lin LIN, Yao FU, lei LIU, Qing xiang guo Department of Chemistry, University of Science and Technology of China, Hefei 230026 Department of Chemistry University of Science and Technology of China

C4'-H bond dissociation enthalpies of nucleosides were predicted using theoretical methods to a precision of 1-2 Kcal/mol. It was found that the stability of the C4' nucleoside radical is slightly dependent on the bas... 详细信息

关键词： Nucleoside homolysis bond energy DNA lesion substituent effect.