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脯氨酸的双功能催化作用对制备光学活性环型羟酮的机理研究
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作者 叶秀林 《化学学报》 SCIE CAS CSCD 北大核心 2001年第10期1680-1685,共6页
2-甲基-2-乙酰乙基-l,3-环戊二酮(1),在双功能催化剂L-(-)-脯氨酸的作用下,生成(+)-cis9S-羟基-8S-甲基氢茚-l,5-二酮[(+)-2],化学产率100%,光学纯度93.4%e.e.;而在L-(+)-高脯氨酸的作用下,得到的是(-)-2,产率73%,光学纯度65%e.e..另一... 2-甲基-2-乙酰乙基-l,3-环戊二酮(1),在双功能催化剂L-(-)-脯氨酸的作用下,生成(+)-cis9S-羟基-8S-甲基氢茚-l,5-二酮[(+)-2],化学产率100%,光学纯度93.4%e.e.;而在L-(+)-高脯氨酸的作用下,得到的是(-)-2,产率73%,光学纯度65%e.e..另一方面,3R-(醛丙硫基)-4-硫杂环己酮可差同异构的衍生物(7)分别在D-或L-脯氨酸催化下,所得到的都是呈右旋光性的非对映立体异构的产物(+)-cis-1,8-二硫杂-4R-羟基-9R,10R-十氢萘-5-酮[(+)-8],但从D-脯氨酸得出的光学纯度高得多这些实验事实和反应机理均可以通过构象分析结合立体结构式得到合理的表达和解释. 展开更多
关键词 脯氨酸 高脯氨酸 双功能催化作用 环型羟酮 光学活性 构象 反应机理
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Synergistic trifunctional electrocatalysis of pyridinic nitrogen and single transition-metal atoms anchored on pyrazine-modified graphdiyne 被引量:3
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作者 Siyun Qi Junru Wang +4 位作者 Xiaohan Song Yingcai Fan Weifeng Li Aijun Du Mingwen Zhao 《Science Bulletin》 SCIE EI CAS CSCD 2020年第12期995-1002,M0003,共9页
Multifunctional catalysts that integrate high efficiency hydrogen evolution reaction(HER), oxygen evolution reaction(OER) and oxygen reduction reaction(ORR) catalytic activity in a single material are attractive for u... Multifunctional catalysts that integrate high efficiency hydrogen evolution reaction(HER), oxygen evolution reaction(OER) and oxygen reduction reaction(ORR) catalytic activity in a single material are attractive for unitized regenerative fuel cells and overall water splitting technologies. As the best-known HER and ORR electrocatalysts, Pt and its alloys have only moderate OER activity. Ruthenium and iridium oxides exhibit the highest OER activities but not as active as Pt for HER and ORR. Here, we proposed a general principle for achieving trifunctional electrocatalysis for three reactions in a single material. Using the newly-synthesized pyrazine-modified graphdiyne(PR-GDY) as an example, we demonstrated that the synergistic effect of the pyridinic nitrogen and anchored transition-metal(TM) single atoms renders highly-efficient HER/OER/ORR trifunctional electrocatalytic activity. For the Ni-doped PR-GDY, the overpotentials for HER, OER and ORR can be respectively as low as -0.05, 0.29 and 0.38 V, which are comparable or even superior to the best-known single-functional and bi-functional precious electrocatalysts.These computational results offer not only a promising trifunctional electrocatalyst but also a strategy for the design of multifunctional electrocatalysts. 展开更多
关键词 Trifunctional electrocatalysts Pyrazine-modified graphdiyne(PR-GDY) Single atoms Density-functional theory
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