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2,11-Dimethoxyldipyridopurinone as an efficientreducing visible-light photocatalyst for organic transformations

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Organic Chemistry Frontiers 2022年第6期9卷 1634-1641页

作者： Yameng Wan Qingfeng Liu Hao Wu Zhiguo zhang guisheng zhang Key Laboratory of Green Chemical Media and Reactions Ministry of EducationCollaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsHenan Key Laboratory of Organic Functional Molecules and Drug InnovationNMPA Key Laboratory for Research and Evaluation of Innovative DrugSchool of Chemistry and Chemical EngineeringHenan Normal University46 East of Construction RoadXinxiangHenan 453007China

We report for the first time 2,11-dimethoxyldipyridopurinone (DP4) as a potent reducing visible-lightphotocatalyst toward three prototypic organic transformations: redox-neutral intramolecular aryltrifluoromethylations of acrylamides and the direct C–H arylation of heteroarenes with aryl diazonium salts, netoxidative hydroxylations of arylboronic acids using molecular oxygen as a green oxidant, and the netreductive dehalogenation/deuteration of α-bromocarbonyl compounds. This work reveals a bright futurefor dipyridopurinone derivatives as a new class of metal-free visible-light photocatalysts for a wide rangeof organic transformations.

关键词： visible catalyst boron

An Efficient, Three-component One-pot Preparation of 1,4-Dihydropyridines Containing Novel Substituted Pyrazole under Sulfamic Acid Catalysis

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Chinese Journal of Chemistry 2011年第3期29卷 511-514页

作者： Li, Jianping Qiu, Jikuan Li, Huijuan zhang, guisheng College of Chemistry and Environmental Science Key Labaratory of Green Chemical Media and Reactions Ministry of Education Henan Normal University Xinxiang Henan 453007 China

An efficient approach to 1,4-dihydropyridines containing novel substituted pyrazole is achieved via threecomponent reaction of pyrazolyl aldehyde, β-ketoester, and ammonium acetate in one-pot under sulfamic acid cata... 详细信息

关键词： Hantzsch reaction 1,4-dihydropyridines pyrazole sulfamic acid catalysis synthesis

Selenium-catalyzed oxidative carbonylation of 1,2,3-thiadiazol-5-amine with amines to 1,2,3-thiadiazol-5-ylureas

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Chinese Chemical Letters 2019年第2期30卷 375-378页

作者： Xiaopeng zhang Shuxiang Dong Qianqian Ding Xuesen Fan guisheng zhang Henan Key Laboratory of Organic Functional Molecules and Drug Innovation Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University

A facile one-pot, economical approach to 1,2,3-thiadiazol-5-ylureas was developed via seleniumcatalyzed oxidative carbonylation of 1,2,3-thiadiazol-5-amine with a series of amines in one-pot manner in the presence of CO and O_2. This approach is featured with cheap and easily available raw materials,cheap and reusable catalyst selenium, one-pot procedure, high atomic economy, simple operations and no emission of corrosive wastes.

关键词： Selenium Oxidative carbonylation 1,2,3-Thiadiazol-5-amine 1,2,3-Thiadiazol-5-ylureas Phase-transfer catalysis

Anion cascade reactions Ⅲ:Synthesis of 3-isoquinuclidone bridged polycyclic lactams

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Chinese Chemical Letters 2024年第2期35卷 426-430页

作者： Zhiguo zhang Bingbing Shi Xiyang Cao Nana Ma Hao Wu Xingjie zhang guisheng zhang Key Laboratory of Green Chemical Media and Reactions Ministry of EducationCollaborative Innovation Centre of Henan Province for Green Manufacturing of Fine ChemicalsNMPA Key Laboratory for Research and Evaluation of Innovative DrugSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang 453007China

Bridged polycyclic lactams are important structural units in organic functional materials,natural products,and pharmaceuticals.A flexible and efficient anion cascade reaction was developed for the preparation of bridged polycyclic lactams from readily available malonamides and 1,4‑*** highly substituted bridged polycyclic lactams were synthesized in good to excellent yields by tandem nucleophilic sequences in the presence of t BuOK in commercially available EtOH solvent at 60℃.Notably,the simple reactions can be run on a gram ***,bis-Michael addition reaction and hemiaminalization reactions are involved in the tandem transformation.

关键词： Anion cascade reactions 3-Isoquinuclidone Bridged polycyclic lactams Bis-Michael addition reaction Hemiaminalization

Copper（I）-Catalyzed Intramolecular N-N Coupling of Cyclopropyl O-Acyl Ketoximes： Synthesis of Spiro-fused Pyrazolin-5-ones

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Chinese Journal of Chemistry 2016年第12期34卷 1309-1320页

作者： Zhiguo zhang Junlong Li Guoqing Huang Kai Sun guisheng zhang Nana Ma Qingfeng Liu Tongxin Liu Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University Xinxiang Henan 453007 China Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis Northeast Normal University Changchun Jilin 130024 China Handan Purification Equipment Research Institute Handan Hebei 056027 China College of Chemistry and Chemical Engineering Anyang Normal University Anyang Henan 455000 China

A convenient copper-catalyzed approach has been developed for the synthesis of substituted spiro-fused pyrazolin-5-ones from readily available cyclopropyl O-acyl ketoximes via an intramolecular N-N bond formation reac... 详细信息

关键词： copper-catalyzed N-Nbond formation O-acyl ketoximes pyrazolin-5-ones cyclopropyl oximes

Synthesis of[60]Fullerene-Fused Allylbenzofurans via Palladium-Catalyzed Migration Reaction

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Chinese Journal of Chemistry 2023年第14期41卷 1733-1739页

作者： Tong-Xin Liu Panting Yang Nana Ma Xiaojun Li Xin Wang Jinliang Ma guisheng zhang Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Key Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007 China

Chemical functionalization of fullerenes has been an important topic in fullerene chemistry. Herein, an unprecedented Pd-catalyzed migration reaction of [60]fullerene with allyloxy-tethered aryl iodides is present for the preparation of novel [60]fullerene-fused allylbenzofurans. The use of 1,2-bis(diphenylphosphino)benzene (DPPBz) as a ligand is crucial for the success of the transformation. The reaction shows high chemo- and regioselectivity, and is flexible with regard to allyl-migration site, providing a new and efficient approach to rare [60]fullerene-fused benzofurans. Control experiments disclose that the reaction most probably undergoes a sequential C—O bond cleavage/allyl-migration/intermolecular cycloaddition cascade process.

关键词： Fullerenes Transition-metal catalysis Cross-coupling Cycloaddition Oxygen heterocycles

Metal-free nucleophilic 7,8-dearomatization of quinolines:Spiroannulation of aminoquinoline protected amino acids

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Chinese Chemical Letters 2023年第2期34卷 219-223页

作者： Zhiguo zhang Xiyang Cao Xiaoqing Song Gang Wang Bingbing Shi Xiang Li Nana Ma Lantao Liu guisheng zhang Key Laboratory of Green Chemical Media and Reactions Ministry of EducationCollaborative Innovation Centre of Henan Province for Green Manufacturing of Fine ChemicalsNMPA Key Laboratory for Research and Evaluation of Innovative DrugSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang 453007China The College of Chemistry and Chemical Engineering Shangqiu Normal UniversityShangqiu 476000China

Atom-and step-economy in IBX assisted diversity-oriented synthesis is achieved with a versatile AQ auxiliary α-amino acid analogs offering rapid access to polycyclic spiro-quinolines featuring a quaternary stereocenter in 20%–91% yields under mild conditions via 7,8-dearomatization of quinolines. Free of a preinstalled activation group is highlight of this intramolecular oxidation spiroannulation tandem reaction. This type of N-heterospirocycles, traditionally difficult to access, may open the door to a potentially interest scaffold for synthetic and medicinal chemistry.

关键词： Dearomatization Spiroannulation Aminoquinoline Amino acids Hypervalent iodine reagents

Sum-difference Reduced-dimensional Processing in SAR Image Domain and Statistical Analysis for Ground Moving Target Indication

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Chinese Journal of Aeronautics 2009年第6期22卷 620-626页

作者： Yang Zhiwei Liao guisheng zhang Juan Zeng Cao National Lab of Radar Signal Processing Xidian University Xi 'an 710071 China

In this article, a new reduced-dimensional adaptive processing algorithm based on joint pixels sum-difference data for clutter rejection is proposed. The sum-difference data are obtained by orthogonal projection of the joint pixels data of different synthetic aperture radar （SAR） images generated by a multi-satellite radar system. In the sense of statistical expectation, the sum-difference data contain the common and different information of the SAR images. Therefore, the objective of clutter cancellation can be achieved by adaptive processing. Moreover, based on the residual image after clutter rejection, statistical analysis of constant false-alarm rate （CFAR） detection of moving targets is also presented. Simulation results demonstrate the effectiveness and robustness of the proposed algorithm even with heterogeneous clutter and image co-registration error.

关键词： ground moving target indication space-time adaptive processing clutter rejection multi-channel synthetic aperture radar

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川西坳陷须家河组致密砂岩储层裂缝特征

天然气工业 2005年第7期25卷 11-13,26页

作者：张贵生中国石化西南分公司勘探开发研究院

研究成果表明,川西坳陷上三叠统须家河组由于深埋、经历地史时期长、岩石成岩作用强烈,因而储层物性总体较差,尤其是须二段,孔隙度小于5%,渗透率一般小于0.1×10-3μm2,属于致密-超致密砂岩范畴。现今储层的基质孔、渗已不能满足天然气... 详细信息

研究成果表明,川西坳陷上三叠统须家河组由于深埋、经历地史时期长、岩石成岩作用强烈,因而储层物性总体较差,尤其是须二段,孔隙度小于5%,渗透率一般小于0.1×10-3μm2,属于致密-超致密砂岩范畴。现今储层的基质孔、渗已不能满足天然气的规模运聚,天然气的富集、产出和高产强烈依赖于裂缝对储层储集条件的改善,因此,裂缝研究对油气勘探有着极为重要的意义。文章通过对野外露头、钻井岩心裂缝和岩石薄片微裂缝的观察描述、统计和分析,并采集裂缝充填矿物(方解石、石英)样品进行稳定同位素检测、包体测温检测和ESR测年实验分析,基本明确了裂缝的成因类型、裂缝特征、裂缝形成期次及其与天然气产能的关系。

关键词：裂缝特征须家河组川西坳陷致密砂岩储层同位素检测 ESR测年天然气研究成果上三叠统成岩作用储层物性储集条件油气勘探野外露头岩石薄片岩心裂缝实验分析成因类型形成期次孔隙度渗透率微裂缝方解石