检索结果-南通市图书馆

Pd-Catalyzed Dearomatization of Indole Derivatives via Intermolecular heck Reactions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2020年第3期38卷 235-241页

作者： Ping Yang Ren-Qi Xu Chao Zheng Shu-Li You State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Ling ling LuShanghai 200032China

Pd-catalyzed intermolecular dearomative heck reaction of indoles with aryl iodides is described.The challenges on both reactivity and regioselectivity are addressed by the judicious regulation of the geometric and electronic properties of the substrates.An array of indoline derivatives bearing C2-quaternary center is obtained in good to excellent yields(up to 93%)with exclusive regioselectivity under operationally simple conditions.The mechanistic proposal is supported by detailed DFT calculations.

关键词： conditions. heck conclusion

Lymphocyte Subsets and Sister-chromatid Exchanges in the Students Exposed to Formaldehyde Vapor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 1999年第2期12卷 88-94页

作者： YING CHEN-JIANG YE XIAO-LEI XIE HONG YAN WEN-SHENG ZHAO MEI-YING XIA TONG AND YIN SHU-YI.(Department of Environmental Health, Tongji Medical University, Wuhan 430030, China Department of Public Health, Wenzhou Medical College, Wenzhou 317400, China Department of Anatomy,Tongji Medical University, Wuhan 430030, China) 同济医科大学环境健康系湖北武汉温州医学院公共卫生系浙江温州 317400 同济医科大学解剖学系湖北武汉

The present report evaluates the effects of formaldehyde (FA) exposure on peripheral lymphocytes by using heth genetic and immunological parameters. Twenty-three non-smoking students in the study had inhalation exposure to 0.508 ±0. 299 mg/m3 of FA for a Period of 8 weeks (3h × 3 times each week) during anatomy classes. As for composition of lymphocyte subsets after FA exposare,significant increase was found in the percentage of CD19(B cells), while sighficant decrease was observed in CD3(total T cells), CD4(T helper-inducer cells), and CD8(T cytotoxic-suppressior cells) with a P 0 .05) was reported between lymphocyte prolifendion rate and sisterchromatid exchange (SCE) at the exposure level and duration. It is suggested that the lymphocyte subsets may be most susceptible to the effects of FA, though a single immunological endpoint is rarely related with pathophysiological interpretation.

关键词： Res FA DNA Lymphocyte Subsets and Sister-chromatid Exchanges in the Students Exposed to Formaldehyde Vapor heck

Enhancing the catalytic efficiency of the heck coupling reaction by forming 5 nm Pd octahedrons using kinetic control

在线全文

学校读者我要写书评

暂无评论

纳米研究：英文版 2015年第6期8卷 2115-2123页

作者： Ran Long Di Wu Yaping Li Yu Bai Chengming Wang Li Song Yujie Xiong Hefei National Laboratory for Physical Sciences at the Microscale Collaborative Innovation Center of Chemistry for Energy Materials School of Chemistry and Materials Science and National Synchrotron Radiation Laboratory University of Science and Technology ot China Hefei Anhui 230026 China

异构的催化作用通过界面的反应的一个过程发生；因此，表面方面和尺寸控制能增加催化效率。八面的 Pd nanocrystals，围住由 { 111 } 方面，应该是理想的几何形状为哎呀联合反应；然而，综合是挑战性的有用存在帽子代理人技术的相对一... 详细信息

异构的催化作用通过界面的反应的一个过程发生；因此，表面方面和尺寸控制能增加催化效率。八面的 Pd nanocrystals，围住由 { 111 } 方面，应该是理想的几何形状为哎呀联合反应；然而，综合是挑战性的有用存在帽子代理人技术的相对一致的尺寸分布的 5 nm Pd 八面体。这里，我们把钯用作一个模型系统调查原子增加的动力学怎么能精确用注射泵被控制。作为结果，我们的方法生产了象 5 nm 一样小的 Pd 八面体，它增加了催化效率哎呀当减少使用的催化剂的重量时，联合反应。

关键词：动力学控制纳米晶体催化效率偶联反应 heck 钯八面体界面反应

Magnetically recyclable Pd/γ-AlOOH@Fe_3O_4 catalysts and their catalytic performance for the heck coupling reaction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2014年第6期57卷 866-872页

作者： YANG Hao JI ShengFu LIU XueFei ZHANG DanNi SHI Da State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

Novel magnetically recyclable Pd/γ-AlOOH@Fe3O4 catalysts were prepared using γ-AlOOH@Fe3O4 as a magnetic supporter and nano-Pd particles as the active catalytic component.The structure of the catalysts was characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),N2 adsorption-desorption,and a vibration sample magnetometer(VSM).The catalytic activity and recyclability for the heck coupling reaction were investigated.Results showed that the magnetic γ-AlOOH@Fe3O4 possessed a core-shell structure,as well as that the nano-Pd particles were 6–8 nm and had been well dispersed in the γ-AlOOH shell.In the heck coupling reactions,the magnetic Pd/γ-AlOOH@Fe3O4 catalysts exhibited good catalytic activity and recyclability.For the(0.021 mol%)Pd/γ-AlOOH@Fe3O4 catalyst,the bromobenzene conversion and product yield reached about 100%and 96.3%,respectively,under a 120°C reaction temperature and 12 h reaction time.After being recycled 8 times,the conversion of bromobenzene and the recovery of the catalyst were about 90%and 93%,respectively.The nano-Pd particles were kept well dispersed in the used Pd/γ-AlOOH@Fe3O4 catalyst.

关键词：催化剂制备磁性载体偶联反应 heck 可回收 Pd 催化性能 Fe3O4

Pd-Catalyzed Intermolecular Dearomative heck Reaction of Indole Derivatives

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2020年第5期38卷 525-526页

作者： Ping Yang State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai 200032China

Dearomatization of indole derivatives[1,2]provides a straightforward approach for synthesizing diverse indolines which serve as the structural core of numerous natural products and pharmaceuticals.[3]Over the past decade,Pd-catalyzed heck reaction[4]has been applied in the dearomatization of indoles.In this regard,several elegant intramolecular dearomative heck reactions of indoles have been developed.[s]However,to date,the reported works are mainly limited to intramolecular reactions,which proceed viaβ3-hydride elimination or trapping by an additional nucleophile(Scheme 1(a)).However,additional synthetic elaboration is usually required to access appropriate substrates for the key dearomatization step,thus reducing the synthetic efficiency.

关键词： intramolecular heck straight

有氧条件下聚(氯乙烯)负载Pd(Ⅱ)配合物高效催化heck和无铜Sonogashira反应(英文)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

催化学报 2014年第3期35卷 324-328页

作者： Mohammad Bakherad Ali Keivanloo Shahrzad Samangooei School of Chemistry Shahrood University of Technology

A novel poly(vinyl chloride)-supported Pd complex was found to be a highly active catalyst for the heck and Sonogashira reactions of aryl halides under aerobic conditions.The complex is thermally stable,and can be easily recovered and reused.The catalyst was recycled for the heck and Sonogashira reactions for five runs without appreciable loss of its catalytic activity,and with negligible metal leaching.

关键词： heck 催化剂氯乙烯反应好氧条件 Pd 载体配合物

Sadphos促进的苯并三氮唑与1,3-二烯的不对称串联脱氮heck/Tsuji-Trost反应

在线全文

学校读者我要写书评

暂无评论

有机化学 2021年第11期41卷 4512-4514页

作者：李芸杉唐叶峰清华大学药学院生命有机磷化学及化学生物学教育部重点实验室北京100084

过渡金属催化的不对称脱氮环加成反应是构建手性氮杂环化合物的有力工具^([1]).Fokin课题组^([2])率先发展了手性Rh催化的1,2,3-三氮唑与各种不饱和化合物的不对称脱氮环加成反应.Murakami课题组系统性地研究了手性Rh或Ni催化的1,2,3-... 详细信息

过渡金属催化的不对称脱氮环加成反应是构建手性氮杂环化合物的有力工具^([1]).Fokin课题组^([2])率先发展了手性Rh催化的1,2,3-三氮唑与各种不饱和化合物的不对称脱氮环加成反应.Murakami课题组系统性地研究了手性Rh或Ni催化的1,2,3-三氮唑^([3])、1,2,3,4-四氮唑^([4])、1,2,3-苯并三氮酮^([5])与各种不饱和化合物的不对称脱氮环加成反应.

关键词：环加成反应氮杂环化合物不饱和化合物过渡金属催化苯并三氮唑 heck 四氮唑

纳米钯催化芳基重氮盐的Suzuki和heck偶联反应

在线全文

学校读者我要写书评

暂无评论

有机化学 2015年第2期35卷 478-483页

作者：赵晓霞常宏宏李兴魏文珑太原科技大学化学与生物工程学院太原030021 太原理工大学化学化工学院太原030024

开发了一种使用纳米Al2O3作载体,由四三苯基膦钯衍生的纳米钯催化剂催化的使用芳基重氮盐作原料的高效绿色Suzuki和heck偶联反应来制备联苯类和芳基烯类化合物的方法.该反应体系以乙醇作反应溶剂,在空气中于25℃下,催化剂可高效催化芳... 详细信息

开发了一种使用纳米Al2O3作载体,由四三苯基膦钯衍生的纳米钯催化剂催化的使用芳基重氮盐作原料的高效绿色Suzuki和heck偶联反应来制备联苯类和芳基烯类化合物的方法.该反应体系以乙醇作反应溶剂,在空气中于25℃下,催化剂可高效催化芳基重氮盐分别与芳基硼酸和烯烃的Suzuki和heck偶联反应,各类考察的反应底物都给出较高的收率,而且催化剂循环利用4次后,其催化活性和反应收率都没有明显降低.

关键词：纳米钯 Suzuki heck Pd/Al2O3 联苯类化合物芳基烯

在线全文

学校读者我要写书评

暂无评论

锰催化未活化烯烃的氢芳化反应

有机化学 2020年第11期40卷 3973-3975,M0015页

作者：何恒驰谢劲南京大学化学化工学院配位化学国家重点实验室江苏省先进有机材料重点实验室南京210023

过渡金属催化烯烃的官能团化已成为构建化学键的高效策略.由于未活化的烯烃反应活性低,且对C=C键的区域选择性控制通常较差,因此与活化烯烃相比,未活化烯烃的精确官能团化是该领域的一大挑战.从反应机制上看,原位形成的C(sp3)-M中间体... 详细信息

过渡金属催化烯烃的官能团化已成为构建化学键的高效策略.由于未活化的烯烃反应活性低,且对C=C键的区域选择性控制通常较差,因此与活化烯烃相比,未活化烯烃的精确官能团化是该领域的一大挑战.从反应机制上看,原位形成的C(sp3)-M中间体往往倾向于进行β-H消除,并产生heck型产物,这为选择性调控增加了难度.近年,一种新的配位辅助策略被应用于过渡金属催化的未活化烯烃氢芳化.

关键词：区域选择性过渡金属催化官能团化高效策略反应机制化学键 heck 选择性调控