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Diastereodivergent[4+2]annulation of biphenylenes with enones via nickel(0)-catalyzed C-C bond activation

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Chinese Chemical Letters 2022年第12期33卷 5056-5060页

作者： Junyan Chen Dachang Bai Xiuli Guo Yiyao Wang Xingwei Li NMPA Key Laboratory for Research and Evaluation of Innovative Drug Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang 453007China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical Engineering Shaanxi Normal University(SNNU)Xi'an 710062China

Ni(0)-catalyzed regio-and diastereodivergent[4+2]annulation of biphenylenes withα,βunsaturated ketones is described.This solvent-controlled diastereodivergent reaction integrates C-C bond cleavage of biphenylene and C=C double bond insertion selectivity,offering a mild approach to all possible diastereoisomers of 9,10-dihydrophenanthrene derivatives from the same starting materials.

关键词： Nickel Enones Biphenylenes Diastereodivergent annulation C-C activation 9,10-Dihydrophenanthrenes

Catalytic[3+3]Annulation ofβ-Ketoethers and Cyclopropenones via C(sp^(3))-O/C-C Bond Cleavage under Transition-Metal Free Conditions

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Chinese Journal of Chemistry 2021年第10期39卷 2769-2773页

作者： Dachang Bai Junyan Chen Bingbing Zheng Xueyan Li Junbiao Chang NMPA Key Laboratory for Research and Evaluation of Innovative Drug Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Main observation and conclusion The efficient cleavage of carbon-oxygen(C—O)bond is highly important for the transformation of oxygen-rich biomass and industry chemicals.Herein,an efficient[3+3]annulation ofβ-ketoethers with cyclopropenones in the presence of catalytic base has been developed,which proceeds through the C(sp^(3))—O bonds cleavage inβ-ketoethers and C—C bond cleavage in cyclopropenones under transition-metal free conditions.The cleavage of C(sp^(3))—O bonds in alkyl alkyl ethers and aryl alkyl ethers was realized.The reaction featured excellent functional group compatibility and chemoselectivity,affording various 2-pyrones in good to excellent yields under mild conditions and simple operation.

关键词： C-O/C-C activation [3+3]Annulation β-Ketoethers Cyclopropenones Transition-metal free conditions

对映发散式接力不对称偶联策略:实现镍催化环丙基锌试剂的立体选择性官能团化

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有机化学 2021年第4期41卷 1746-1748页

作者：程若诗白大昌河南师范大学化学化工学院河南新乡453007 中国科学院上海有机化学研究所金属有机化学国家重点实验室上海200032

手性化合物在医药、农药、香料和材料等领域的研究和工业生产中有着非常广阔的应用,开发手性分子单一对映体的高效合成方法具有非常重要的意义[1].近些年,镍催化不对称交叉偶联反应已发展为一种非常有效的合成手性化合物的方法.该方法... 详细信息

手性化合物在医药、农药、香料和材料等领域的研究和工业生产中有着非常广阔的应用,开发手性分子单一对映体的高效合成方法具有非常重要的意义[1].近些年,镍催化不对称交叉偶联反应已发展为一种非常有效的合成手性化合物的方法.该方法通常使用二级卤代烃为亲电试剂,在手性镍催化下与不同的金属试剂(通常是一级金属试剂)发生偶联反应得到立体构型单一的手性化合物[2-3].

关键词：手性化合物立体选择性亲电试剂立体构型手性分子镍催化锌试剂偶联反应

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镍催化C—C键活化反应研究进展

有机化学 2020年第6期40卷 1423-1436页

作者：代洪雪吴芬白大昌河南师范大学化学化工学院河南新乡453007

过渡金属催化C—C键活化是有机化学一个热点和难点领域,吸引着人们广泛的关注.C—C键活化可以为很多复杂分子的合成提供简单、快速和原子经济性的方法.相比于钯、铑和铱等过渡金属催化剂,镍催化剂有很多优点,更加经济适用,也表现出独特... 详细信息

过渡金属催化C—C键活化是有机化学一个热点和难点领域,吸引着人们广泛的关注.C—C键活化可以为很多复杂分子的合成提供简单、快速和原子经济性的方法.相比于钯、铑和铱等过渡金属催化剂,镍催化剂有很多优点,更加经济适用,也表现出独特的催化活性,备受化学家们的青睐.主要介绍了近些年镍催化C—C键断裂反应的研究进展.

关键词：镍 C—C键活化过渡金属

On the Application of Mixed Models of Probability and Convex Set for Time-Variant Reliability Analysis

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1981-1999页

作者： Fangyi Li dachang Zhu Huimin Shi Center for Research on Leading Technology of Special Equipment School of Mechanical and Electric EngineeringGuangzhou UniversityGuangzhou510006China

In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems typically involve a complexmultilevel nested optimization problem,which can result in an enormous amount of computation.To this end,this paper studies the time-variant reliability evaluation of structures with stochastic and bounded uncertainties using a mixed probability and convex set model.In this method,the stochastic process of a limit-state function with mixed uncertain parameters is first discretized and then converted into a timeindependent reliability problem.Further,to solve the double nested optimization problem in hybrid reliability calculation,an efficient iterative scheme is designed in standard uncertainty space to determine the most probable point(MPP).The limit state function is linearized at these points,and an innovative random variable is defined to solve the equivalent static reliability analysis model.The effectiveness of the proposed method is verified by two benchmark numerical examples and a practical engineering problem.

关键词： Mixed uncertainty probability model convex model time-variant reliability analysis

Zinc-based metal organic framework with antibacterial and anti-inflammatory properties for promoting wound healing

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Regenerative Biomaterials 2022年第1期9卷 163-174页

作者： Yuting Chen Jinhong Cai dachang Liu Shuhan Liu Doudou Lei Li Zheng Qingjun Wei Ming Gao Guangxi Engineering Center in Biomedical Materials for Tissue and Organ Regeneration The First Affiliated Hospital of Guangxi Medical UniversityNo.22 Shuangyong RoadQingxiu DistrictNanning 530021China Department of Orthopaedics Trauma and Hand Surgery The First Affiliated Hospital of Guangxi Medical UniversityNo.6 Shuangyong RoadQingxiu DistrictNanning 530021China Guangxi Collaborative Innovation Center of Regenerative Medicine and Medical Bioresource Development and Application The First Affiliated Hospital of Guangxi Medical UniversityNo.22 Shuangyong RoadQingxiu DistrictNanning 530021China Guangxi Key Laboratory of Regenerative Medicine The First Affiliated Hospital of Guangxi Medical UniversityNo.22 Shuangyong RoadQingxiu DistrictNanning 530021China

The synergistic effect of antibacterial and anti-inflammatory is needed to overcome the problem of wound healing difficulties.Based on the favorable antibacterial and anti-inflammatory effect of zinc ions(Zn^(2+))and the physicochemical properties of metal organic frameworks(MOFs),we prepared nanosized zinc-based MOF:Zn-BTC with the ability to slowly release Zn^(2+).In cellular levels,Zn-BTC possessed lower toxicity to fibroblasts and enhanced capacity of cell proliferation and migration.It also had good bactericidal effect on multiple drug-resistant bacteria by reducing 41.4%MRSA and 47.2%Escherichia coli.In addition,Zn-BTC also displayed the ability of lowering the expression of antioxidant genes:superoxide dismutase 1,superoxide dismutase 2 and interleukin 6,and enhancing the expression of wound healing genes:transforming growth factors-b and type I collagen.Finally,it also demonstrated that Zn-BTC could effectively improve the skin wound healing of SD rats and had no toxicity on major organs.The favorable biocompatibility,antibacterial and anti-inflammatory properties of Zn-BTC gave a new insight of designing novel MOFs for promoting skin wound healing.

关键词： zinc ions metal organic framework antibacterial anti-inflammatory skin wound healing

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酰胺化合物的核磁共振氢谱

大学化学 2024年第3期39卷 231-238页

作者：吴昊刘珍白大昌河南师范大学化学化工学院抗病毒性传染病创新药物全国重点实验室河南新乡453007

酰胺是一类非常重要的化合物,广泛存在于多肽和生物碱等生物活性分子中,在化工、染料以及药物研发等领域也具有重要的应用价值。因此,学习酰胺化合物的合成以及结构鉴定具有重要的意义。由于酰胺化合物的氮原子上的孤对电子能够离域到羰... 详细信息

酰胺是一类非常重要的化合物,广泛存在于多肽和生物碱等生物活性分子中,在化工、染料以及药物研发等领域也具有重要的应用价值。因此,学习酰胺化合物的合成以及结构鉴定具有重要的意义。由于酰胺化合物的氮原子上的孤对电子能够离域到羰基(C=O)上,导致酰胺RCO―N上的C―N键表现出部分双键性质,C―N键不能自由旋转,使得酰胺化合物的核磁共振氢谱较复杂。本文总结了酰胺的核磁共振氢谱特征,探讨了酰胺异构化的一些影响因素。通过酰胺核磁共振氢谱的学习,培养学生对核磁共振谱图解析的能力,并加深对酰胺类化合物的理解和认识。

关键词：酰胺化合物核磁共振氢谱异构化

Land cooperatives as an approach of suburban space construction： Under the reform of Chinese land transfer market

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Frontiers of Architectural Research 2016年第4期5卷 425-432页

作者： Sheng Dang dachang Yuan Weiyuan Kong School of Architecture Tianjin University Tianjin 300072 China

In China, the urban-rural dual structure of land market has resulted in urban sprawl caused by industrial diffusion. Urban sprawl disintegrated agricultural communities in suburbs, thereby increasing the unemployment rate among farmers who lost their lands. To address this problem, the Chinese government proposed a reform program to analyze the monopoly of the government in the land market and guarantee the property rights of farmers. This study analyzed the connection between land market mechanism and suburban space formation. Results concluded that the current land transfer system caused industrial urban sprawl, and the reform program may promote the urban sprawl of population. Two typical models of rural land development were studied. A model called land cooperatives based on land pooling joint stock system was proposed to build a compact and sustainable suburban space.

关键词： Land institution Suburban space Urban sprawl Land cooperatives

Topology optimization of a 6-DOF spatial compliant mechanism based on Stewart propotype platform

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Acta Mechanica Sinica 2019年第5期35卷 1044-1059页

作者： dachang Zhu Wanghu Zhan School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou 510006China

To improve the global stiffness and conveniently build a model of a compliant mechanism with spatial multiple degrees of freedom(DOF),the topology optimization method,combined with the isomorphic mapping matrix,is proposed in this paper for structure synthesis of a 6-DOF spatial compliant mechanism.By using the differential approximation method,the Jacobian matrix of the Stewart prototype platform is calculated as the isomorphic mapping matrix,and its eigenvalues and eigenvectors are considered.Combining the isomorphic mapping matrix with the solid isotropic material with the penalization topology optimization method,the topological model of the 6-DOF spatial compliant mechanism is constructed,and a topological structure of the 6-DOF spatial compliant mechanism is derived which has the same differential kinematic characteristics as the Gough-Stewart prototype platform.Piezoelectric actuators are mounted inside the topological structure during the three-dimensional printing manufacturing process,and its driver directions are in accordance with the driver configuration directions of the Gough-Stewart prototype platform.The effectiveness of the proposed method for topological structure synthesis of the 6-DOF spatial compliant mechanism is demonstrated through several numerical examples and experimental studies.

关键词： 6-DOF spatial compliant mechanism Stewart prototype platform Isomorphic mapping Jacobian matrix Topology optimization