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Catalytic Asymmetric Cross-Dehydrogenative Coupling of 2H-Chromenes and Aldehydes

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Chinese Journal of Chemistry 2018年第12期36卷 1187-1190页

作者： Xinhui Pan xigong liu Shutao Sun Zhilin Meng Lei liu School of Pharmaceutical Sciences Shandong UniversityJinanShandong 250012China School of Chemistry and Chemical Engineering Shandong UniversityJinanShandong 250100China Key Laboratory of Xinjiang Phytomedicine Resource and Utilization Ministry of EducationSchool of Pharmaceutical SciencesShihezi UniversityShiheziXinjiang 832002China

The first catalytic asymmetric cross‐dehydrogenative coupling of 2H‐chromenes with aldehydes using o‐chloranil (3,4,5,6‐tetrachloro‐1,2‐ benzoquinone) as an oxidant has been described. The organocatalytic process is tolerated with a broad range of structurally and electronically varied 2H‐chromenes and aldehydes with good yield and high enantiocontrol. The first catalytic asymmetric cross‐dehydrogenative coupling of 2H‐chromenes with aldehydes using o‐chloranil as an oxidant has been described. The organocatalytic process is tolerated with a broad range of structurally and electronically varied 2H‐chromenes and aldehydes with good yield and high enantiocontrol. [ABSTRACT FROM AUTHOR]

关键词： 2H‐chromene aldehyde asymmetric catalysis C—H functionalization oxidation synthetic method

Copper-Catalyzed [3 + 2 + 1] Cycloaddition of Alkenes with Benzoquinones and Dicarbonyl Compounds via Tandem Oxidative Dicarbofunctionalization/Cyclization Sequence

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Chinese Journal of Chemistry 2022年第14期40卷 1681-1686,I0002页

作者： Tianxing Du Song Li Yunfei He Huan Long xigong liu Hai-Bei Li Lei liu School of Chemistry and Chemical Engineering Shandong University JinanShandong 250100China School of Ocean Shandong UniversityWeihaiShandong 264209China

Developed is an efficient three-component [3 + 2 + 1] cycloaddition of simple alkenes with two C—H substrates via oxidative dicarbofunctionalization/cyclization sequence. The copper-catalyzed reaction involves the formation of two C—C bonds and one C—O bond through the cleavage of three C—H bonds in a single operation. The method has an excellent functional group tolerance, and features a broad substrate scope, affording a variety of functionalized chromenes in good yields.

关键词： Alkene dicarbofunctionalization Cyclization Three-component C-H Activation Oxidation

Enantioselective oxidative C-H functionalization of heterocycles

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Enantioselective oxidative C-H functionalization of heterocy...

Cladophora as ecological engineer:A new test from the largest lake of Qinghai-Tibet plateau with filamentous algal blooms

中国化学会全国第十一届有机合成化学学术研讨会

作者： Zhilin Meng Shutao Sun xigong liu Lei liu Key Laboratory of Chemical Biology（Ministry of Education） School of PharmacyShandong University

＜正＞α-Substituted heterocycles like benzopyrans,tetrahydropyrans,tetrahydrofurans,tetrahydroisoquinolines,tetrahydroquinolines,and piperidines,represent ubiquitous structural motifs in numerous alkaloids exhibiting a wide range of pharmacological *** C-H functionalization of the heterocycles with a variety of carbon nucleophiles presents an atom-economic protocol without prior installation of activating groups,and is therefore

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Water Biology and Security 2024年第1期3卷 46-52页

作者： Zhihua Wu xigong Yuan Xiong Xiong Hongyi Ao Chenxi Wu Guoxiang liu Huan Zhu Institute of Hydrobiology Chinese Academy of SciencesWuhan430072China College of Science Tibet UniversityLhasa850001China Huaihe River Commission of the Ministry of Water Resources Bengbu233001China

Filamentous algae blooms(FABs)have been increasing globally in recent years,and their presence can have both harmful and beneficial effects on aquatic *** one of the most common FABs,Cladophora blooms have been reported in the lakes of the Qinghai-Tibet Plateau during the past few ***,there have been few studies focused on how FABs impact other aquatic organisms,especially in alpine lakes since these are at the forefront of responding to global climate *** this study,the phytoplankton communities in different regions of Qinghai Lake were profiled in different seasons using meta-barcode *** phytoplankton assemblages in areas with Cladophora blooms were compared to those without *** phytoplankton community structure correlated with physicochemical properties including water temperature,electrical conductivity,nitrate,and the presence or absence of Cladophora *** relative abundance of Bacillariophytes was found to be higher in zones with Cladophora blooms than in other *** seasonal changes in phytoplankton biomass andβdiversity were observed in zones with Cladophora *** and microbial degradation of Cladophora can change the pH,dissolved oxygen,secchi depth,and *** with seasonal temperature and electrical conductivity changes,Cladophora growth can significantly impact the phytoplankton biomass,community dissimilarity and assembly *** results showed that Cladophora plays a key role in littoral aquatic ecosystem ecology.

关键词： Filamentous algal blooms Qinghai lake Biodiversity Phytoplankton community Assembly processes Environmental drivers

A “Hemiaminal/Acetal Pool” Strategy for Catalytic Asymmetric Oxidative C-H Functionalization of Heterocycles

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A “Hemiaminal/Acetal Pool” Strategy for Catalytic Asymmetr...

Na_(2)CO_(3)催化的叠氮三甲基硅烷对δ-三氟甲基-δ-芳基取代对亚甲基苯醌的1,6-共轭加成:高效构建含三氟甲基和叠氮取代的二芳基甲烷化合物

中国化学会全国第十二届有机合成化学学术研讨会

作者： Meng,Zhilin liu,xigong Sun,Shutao Wan,Miao liu,Lei School of Chemistry and Chemical Engineering Shandong University

Enantiopure α-substituted heterocycles are among the most prevalent scaffolds comprising a wide assortment of biologically active natural products and *** oxidative C–H functionalization of heterocycles presents an atom-economic protocol without prior installation of activating groups,and is therefore *** impressive progress has recently been achieved in the area,the substrate scope is merely limited to highly reactive heterocycles,such as N-aryl tetrahydroisoquinolines and 9H-xanthenes. Therefore,we developed a "hemiaminal/acetal pool" strategy,which allowed the highly catalytic enantioselective oxidative C–H functionalization of cyclic carbamates and ethers with diverse coupling partners. The scope of heterocycles is broad,with N-acyl tetrahydroquinolines,tetrahydro-β-carbolines,piperidines,and benzopyrans well *** methods exhibit excellent potential in complex molecule synthesis and medicinal chemistry study.

关键词： heterocycle C-H functionalization catalytic asymmetric hemiaminal/acetal pool

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高等学校化学学报 2021年第9期42卷 2772-2781页

作者：刘华铮潘小光李华万仁忠刘希功山东农业大学动物科技学院泰安271018 山东大学化学与化工学院济南250100

报道了一种高效的δ-三氟甲基-δ-芳基-取代对亚甲基苯醌的叠氮化芳基化反应.以Na_(2)CO_(3)为催化剂,叠氮三甲基硅烷与δ-三氟甲基-δ-芳基取代对亚甲基苯醌发生1,6-共轭加成反应,以优异的分离产率(90%~96%)获得了结构多样的含有三氟... 详细信息

报道了一种高效的δ-三氟甲基-δ-芳基-取代对亚甲基苯醌的叠氮化芳基化反应.以Na_(2)CO_(3)为催化剂,叠氮三甲基硅烷与δ-三氟甲基-δ-芳基取代对亚甲基苯醌发生1,6-共轭加成反应,以优异的分离产率(90%~96%)获得了结构多样的含有三氟甲基和叠氮取代的二芳基甲烷化合物.该反应具有良好的底物适用范围和官能团兼容性.

关键词：二芳基甲烷叠氮化合物 δ-三氟甲基-δ-芳基-取代 1,6-共轭加成

基于δ-腈基取代对亚甲基苯醌1,6-氮杂共轭加成的大位阻α-氰胺合成研究

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有机化学 2020年第11期40卷 3934-3943,M0014页

作者：王琳王楠齐越孙书涛刘希功李伟刘磊山东中医药大学药学院济南250355 山东大学化学与化工学院济南250100 山东省肿瘤防治研究院(山东省肿瘤医院) 山东第一医科大学(山东省医学科学院)济南250117

目前对亚甲基苯醌参与的1,6-共轭加成反应的研究主要集中在对预先合成的δ-单取代底物进行三级碳中心的构建.报道了一级芳胺对预先制备的δ氰基-δ-芳基二取代对亚甲基苯醌的1,6-氮杂共轭加成反应,高效地合成了一系列含有四级碳手性中... 详细信息

目前对亚甲基苯醌参与的1,6-共轭加成反应的研究主要集中在对预先合成的δ-单取代底物进行三级碳中心的构建.报道了一级芳胺对预先制备的δ氰基-δ-芳基二取代对亚甲基苯醌的1,6-氮杂共轭加成反应,高效地合成了一系列含有四级碳手性中心的大位阻胺类化合物.该方法条件温和、反应迅速,同时芳胺和对亚甲基苯醌的适用范围广泛.此外,环状二级胺例如吗啉和咪唑也是合适的亲核试剂.

关键词：对亚甲基苯醌 δ-氰基-δ-芳基二取代大位阻胺氮杂四级碳中心 1,6-氮杂共轭加成

Sc(OTf)_(3)催化的δ-三氟甲基-δ-芳基-双取代对亚甲基苯醌和硫醇的反应:高效合成二芳基甲烷硫醚化合物

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有机化学 2021年第8期41卷 3134-3143页

作者：李华庞靖祥刘华铮赵长印李松王恒山刘希功广西师范大学化学与药学学院药用资源化学与药物分子工程国家重点实验室广西民族医药协同创新中心桂林541004 山东大学化学与化工学院济南250100 山东第一医科大学药物研究所&山东省医学科学院山东省医药生物技术中心山东省罕见病重点实验室国家卫生委员会生物技术药物重点实验室济南250000

报道了一种δ-三氟甲基-δ-芳基-二取代的对亚甲基苯醌和硫醇参与的1,6-共轭加成反应.在5 mol%三氟甲基磺酸钪催化的条件下,得到了结构多样化的含有三氟甲基四级碳中心的二芳基甲烷硫醚.反应具有良好的官能团兼容性和底物范围.此外,烷... 详细信息

报道了一种δ-三氟甲基-δ-芳基-二取代的对亚甲基苯醌和硫醇参与的1,6-共轭加成反应.在5 mol%三氟甲基磺酸钪催化的条件下,得到了结构多样化的含有三氟甲基四级碳中心的二芳基甲烷硫醚.反应具有良好的官能团兼容性和底物范围.此外,烷基硫醇和苄硫醇也适用于该反应.鉴于二芳基甲烷硫醚骨架以及三氟甲基在生物活性分子中的重要性,发展的含有三氟甲基取代四级碳中心的二芳基甲烷硫醚的高效合成方法将为生物活性分子的发现提供一条简洁、高效的策略.

关键词： δ-三氟甲基-δ-芳基-二取代对亚甲基苯醌二芳基甲烷硫醚 1,6-共轭加成

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生产建设项目扰动图斑时空分布及合规性分析

中国水土保持科学 2019年第5期17卷 136-145页

作者：段倩岳有志齐斐刘霞杨翔惟黎家作袁希功袁利南京林业大学南方现代林业协同创新中心江苏省水土保持与生态修复重点实验室南京210037 淮河水利委员会淮河流域水土保持监测中心站安徽蚌埠233001

为加强生产建设项目全面监管,有效遏制人为水土流失,保障区域生态环境和社会经济的可持续发展,为区域生产建设项目全过程、全方位监管提供基础数据与技术支撑。本文以安徽霍邱县作为研究区域,探索多源数据、多技术手段相结合的生产建设... 详细信息

为加强生产建设项目全面监管,有效遏制人为水土流失,保障区域生态环境和社会经济的可持续发展,为区域生产建设项目全过程、全方位监管提供基础数据与技术支撑。本文以安徽霍邱县作为研究区域,探索多源数据、多技术手段相结合的生产建设项目扰动图斑时空分布及合规性分析评价。结果表明:1)2015-2016年,霍邱县>0.1 hm^2的生产建设项目扰动图斑共780个,扰动面积8442.14 hm^2,集中分布在霍邱县的西北部、西南部;生产建设项目类型以井采金属矿为主,面积集中在1~5 hm^2,主要扰动变化类型为续建图斑。2)霍邱县已批复的生产建设项目有20项,井采金属矿占批复项目的70%。批复的生产建设项目防治责任范围涉及51个图斑,其中合规图斑有12个,以井采金属矿类型为主;不合规图斑39个,包含疑似建设地点变更的图斑16个,疑似超出防治责任范围的图斑23个。3)霍邱县>1 hm^2疑似未批先建图斑有580个,占>1 hm^2图斑总数的88.68%,大部分为未实施立项的生产建设活动,但也凸显出地方监管力度不足等问题。水行政主管部门监督管理的形势与任务严峻,仍需加强对生产建设项目的精准化监督管理,有效遏制人为水土流失现象。

关键词：生产建设项目水土保持监管扰动图斑合规性分析