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Science China Chemistry 2024年第2期67卷 558-567页

作者： Shan-Shan Li Yu-Shi Jiang Xue-Ling Luo Xuming Ran Yuqiang Li Dong Wu Cheng-Xue Pan Peng-Ju Xia School of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityGuilin541004China Shanghai Artificial Intelligence Laboratory Shanghai200433China The Institute for Advanced studies Wuhan UniversityWuhan430064China

We developed a highly selective and efficient multicomponent transformation by utilizing alkynes and olefins/(hetero)arenes through photoinduced energy-transfer *** reaction involves the formation of three distinct chemical bonds,namely C(sp~3)–C(sp~2),C(sp~2)–C(sp~3),and C(sp~3)–N,in a single coordinated *** strategy used a vinyl radical-mediated radical relay approach under mild conditions,exhibiting a broad substrate scope(>70 examples),excellent functional-group tolerance,and remarkable regio-and *** the utilization of a combination of experimental techniques and density functional theory(dft),we delved deeper into the mechanistic intricacies of this distinctive *** revealed that the selective radical addition to electron-deficient alkynes,rather than olefins,was governed by the inherent reactivity of alkyl *** discovery presented a highly effective approach for the synthesis of stereodefined multisubstituted alkenes.

关键词： alkyne-olefin coupling dft studies regio-and anti-stereoselectivity multisubstituted alkenes

Theoretical Analysis of the Mechanism of Cationic Pd(Ⅱ)-catalyzed Fujiwara-Moritani Reaction

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Chinese Journal of Structural Chemistry 2021年第5期40卷 576-587,528页

作者： REN Ying WANG Tao ZHANG Ting-Ting JIA Jian-Feng WU Hai-Shun Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials ScienceShanxi Normal UniversityLinfen 041000China

A systematic theoretical investigation has been studied on Fujiwara-Moritani reaction between 3-methoxyacetanilide with n-butyl acrylate by means of density functional theory(dft) calculations when two types of Pd(Ⅱ) catalysts are employed. In [Pd(MeCN)_4](BF_4)_2 catalytic cycle, a 1,4-benzoquinone(BQ)-induced C-H activation of trans-(MeCN)_2Pd(BQ)~(2+) with 3-methoxyacetanilide occurs as the first step to give DC-4_(MeCN), facilitating the insertion of n-butyl acrylate and β-hydride elimination, followed by recycling of catalyst through hydrogen abstraction of monocationic BQ fragment. In Pd(OAc)_(2) catalytic cycle, it is proposed that the most favored reaction pathway should proceed in dicationic mechanism involving a BQ-assisted hydrogen transfer for C-H activation by Pd active catalyst(HOAc)_(2)Pd(BQ)^(2+) to generate DC-4_(HOAc), promoting acrylate insertion and β-hydride elimination, followed by the regeneration of catalyst to give the final product. The calculations indicate that the rate-determining step in [Pd(MeCN)_(4)](BF_4)_(2) catalytic system is the acrylate insertion, while it is the regeneration of catalyst in the Pd(OAc)_(2) catalytic system. In particular, the roles of BQ and ligand effects have also been investigated.

关键词： C-H bond activation dft studies Pd(Ⅱ)catalyst reaction mechanism

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Visible-light-induced direct hydrodifluoromethylation of alkenes with difluoromethyltriphenylphosphonium iodide salt

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Chinese Chemical Letters 2023年第1期34卷 322-325页

作者： Xiaojian Ren Qiang Liu Zhixiang Wang Xiangyu Chen School of Chemical Sciences University of the Chinese Academy of SciencesBeijing 100049China

Photoredox-catalyzed hydrodifluoromethylation of alkenes has become an effective method to introduce difluoromethyl group into organic *** the reported methods involve either photocatalysts or superstoichiometric amounts of additives,we herein describe a simple alternative without using photocatalyst or additive for the hydrodifluoromethylation of alkenes,through photoactivation of difluoromethyltriphenylphosphonium iodide *** studies shed light on how the transformation takes place.

关键词： Hydrodifluoromethylation Difluoromethyltriphenylphosphonium iodide salt Alkenes dft studies Photoredox

Highly efficient bis(aminotropone) Ti catalyst for ethylene polymerization

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Chinese Chemical Letters 2011年第2期22卷 213-216页

作者： Reza Sandaroos Saman Damavandi Ali Nazif Maraym Goharjoo Ali Mohammadi Department of Chemistry School of SciencesFerdowsi University of MashhadP.O.Box 91775MashhadIran Department of Chemistry Islamic Azad University of SarvestanSarvestanIran

Synthesis and structure of Ti complex having a pair of chelating aminotropone[O-N]ligand have been *** of density functional theory（dft） studies suggest that bis（aminotropone） Ti complex,when activated with methylaluminoxane （MAO）,have high potential for the polymerization of olefinic *** theoretical studies also show that the active species derived from bis（aminotropone） Ti catalyst normally possess higher electrophilicity nature compared with those produced using bis（phenoxyimine） Ti complexes（Ti-FI catalysts） which are known as high performance olefin polymerization catalysts. Bis（aminotropone） Ti catalyst generates a catalytically active species that has higher electrophilicity than a Ti-FI catalysts.

关键词： Aminotropone Ethylene polymerization dft studies PI catalysts

Crystal Structure, Photoluminescent, and Theoretical studies of 3-Acetyl-8-methoxy-coumarin

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Chinese Journal of Structural Chemistry 2012年第7期31卷 1003-1007页

作者：李靖李祥高王世荣 School of Chemical Engineering and Technology Tianjin University

The structure of 3-acetyl-8-methoxy-coumarin （AMC） was verified by single-crystal X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a=15.073（3）, b=13.068（3）, c=11.549（2）, β=119.92（3）o, V=1971.7（7）3 , Z=8, F（000）=912, D c=1.470 Mg/m3 , Mr=218.20, μ=0.111 mm-1 , the final R=0.0340 and wR=0.0968 for 1446 observed reflections with I 〉 2σ（I）. The UV-vis absorption and fluorescence of AMC were discussed. The compound exhibits strong blue emission under ultraviolet light excitation. The molecular structure of AMC was optimized using density functional theory （dft） at the B3LYP/6-31G（d） level, showing that the optimized geometer parameters are in good agreement with the experiment data. In addition, the HOMO and LUMO levels of AMC were deduced.

关键词： coumarin crystal structure UV-vis fluorescence dft studies

Aryldiazonium salts can serve as nitrogen-based Lewis acid catalysts and their applications in the formation of photoactive charge transfer complexes

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Chinese Chemical Letters 2023年第5期34卷 217-221页

作者： Xiaojian Ren Qiang Liu Zhusheng Yang Zhixiang Wang Xiangyu Chen School of Materials and Architectural Engineering Guizhou Normal UniversityGuiyang 550025China School of Chemical Sciences University of the Chinese Academy of SciencesBeijing 100049China

We report the Lewis acid catalysis of aryldiazonium salts,and their Lewis acidity applications in photogeneration of aryl radicals under additive-,photocatalyst-and transition metal-free *** this visible light-mediated transformation,the Lewis acidic character of aryldiazonium salts enables access to the photoactive charge transfer complex with *** usefulness and versatility of this new protocol are demonstrated through the chalcogenation of a variety of aryldiazonium salts.

关键词： Aryldiazonium salts Nitrogen-based Lewis acid catalysts Dichalcogenides dft studies Photoredox

Comparative studies of Some Novel Cu(II) Polymeric Complexes Derived from Cyanoacetylhydrazine (CAH;L). The Role of Solvents Used on the Structure and Geometry of the Isolated Cu<sup>2+</sup>Complexes

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Open Journal of Inorganic Chemistry 2021年第4期10卷 111-130页

作者： Mohsen M. Mostafa Chemistry Departments Faculty of Science Mansoura University Mansoura Egypt

Novel polymeric Cu2+ complexes derived from the reaction of cyanoacetylhydrazine (CAH;L) with CuCl2•2H2O in different solvents were synthesized and characterized. The isolated solid polymeric complexes were investigated using modern conventional physicochemical and spectral (IR, 1H-NMR, UV-Vis. ESR, Raman), magnetic and thermal studies. The results revealed that CAH behaves in different ways towards the coordination of the Cu2+ ion. The promotion of solvents to the cyano group was discussed on the basis of the solvent and the Cu2+ ion used. Magnetic and spectral studies suggest octahedral geometry is proposed for the Cu2+ complexes. EPR studies indicate the existence of polymeric complexes depending on the results of g-values. The results suggest that the number of copper atoms ranges from three to twelve atoms. The molecular modeling is drawn and some chemical characteristics are calculated such as chemical reactivity and energy components are investigated between the different types of the ligands.

关键词： Polymeric Cu(II) Complexes ESR studies Cyanoacetylhydrazine dft studies

Crystal Packing studies, Thermal Properties and Hirshfeld Surface Analysis in the Zn(II) Complex of 3-Aminopyridine with Thiocyanate as Co-Ligand

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Open Journal of Inorganic Chemistry 2021年第3期11卷 63-84页

作者： Divine Mbom Yufanyi Hubert Jean Nono Amah Colette Benedicta Yuoh Che Dieudonne Tabong Wirsiy Judith Agwara Moise Ondoh Department of Fundamental Science Higher Technical Teachers’ Training College The University of Bamenda Bamenda Cameroon Department of Chemical and Biological Engineering National Higher Polytechnic Institute The University of Bamenda Bamenda Cameroon Department of Chemistry Faculty of Science The University of Bamenda Bamenda Cameroon Department of Chemistry Higher Teacher Training College The University of Bamenda Bamenda Cameroon Department of Inorganic Chemistry Faculty of Science University of Yaounde I Yaounde Cameroon

Reaction of zinc acetate, potassium thiocyanate and the ligand 3-ampy gave the discrete tetrahedral complex [Zn(NCS)2(3-ampy)2] in which 3-ampy chelates in a monodentate fashion through its pyridine-N atom. It was characterized by single crystal X-ray diffraction, infrared, and elemental analysis. Density Functional Theory calculations were performed in order to gain insights into the role of weak molecular interactions in the complex that influence the self-assembly process and crystal packing. X---H (X = H, C, N and S) inter-actions. S-H interactions (30.2%) were found to be the main interactions that hold the molecules in the crystal structure. Furthermore, the thermolysis of the complex was studied in order to evaluate whether it was suitable as a precursor for zinc sulphide.

关键词： Aminopyridine dft studies Hirshfeld Surface Thiocyanate Zinc