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Chiral phosphoramidite ligand-modulated palladium auto-tandem catalysis for asymmetric dehydrogenative dienylation of imines with α-alkenes

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Science China Chemistry 2025年

作者： Zhong-sheng Nong Hao-Fan Qian Ying-Chun Chen pu-sheng wang Liu-Zhu Gong Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Key Laboratory of Drug Targeting and Drug Delivery System (Sichuan University) Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of Pharmacy Sichuan University School of Materials and Chemistry Southwest University of Science and Technology

The development of efficient processes allowing rapid access to complex chiral molecules from easily available alkenes is a long-term pursuit in the synthetic chemistry community. Transition metal-catalyzed asymmetric functionalization of allylic C–H bond represents a unique alternative toward this goal. However, enantioselective dehydrogenative transformation of olefins to value-added optically enriched molecules remains yet to be discovered. Here, we report a highly enantioselective dehydrogenative dienylation of imines with unactivated α-alkenes driven by the synergistic action of palladium complex and carboxylic acid. Chiral phosphoramidite ligands turned out to be superior in modulating the performance of palladium autotandem catalysis and allowed a broad range of α-alkenes and imines to be transformed into chiral dienylamines. Mechanistic studies suggest that the dienes could be in situ generated from α-alkenes through a palladium(0)-mediated dehydrogenative process in the presence of excess benzoquinone oxidants, and then participated in the Pd-chiral phosphoramidite-catalyzed intermolecular vinylogous-type addition to the imines activated by the carboxylic acid co-catalyst. Notably, the second β-H elimination occurring in the dienylation event might be the turnover-limiting step.

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Pd-Catalyzed Asymmetric Allylic C—H Functionalization

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Chinese Journal of Chemistry 2023年第15期41卷 1841-1848页

作者： pu-sheng wang Liu-Zhu Gong Department of Chemistry University of Science and Technology of ChinaHefeiAnhui 230026China Center for Excellence in Molecular Synthesis of CAS University of Science and Technology of ChinaHefeiAnhui 230026China

Comprehensive Summary Pd-catalyzed asymmetric allylic C—H functionalization has emerged as a powerful tool to access chiral,densely functionalized molecules from easily accessible alkenes,enabling the increase of the step-or atom-economy by minimizing functional group manipulations for preparing allylating *** to the inadequacy of stereoselection strategies,the asymmetric allylic C—H functionalization is still in the early *** this essay,we will describe our journey to identification of asymmetric catalytic systems,mechanism of allylic C—H activation,control of stereo-and regioselectivity,and applications in asymmetric synthesis.

关键词： C-H activation Asymmetric catalysis Allylation Palladium Allylic compounds Regioselectivity Alkenes

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Palladium-catalyzed asymmetric allylic C–H alkylation of 1,4-dienes and glycine Schiff bases

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Science China Chemistry 2020年第4期63卷 454-459页

作者： Tian-Ci wang pu-sheng wang Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China Center for Excellence in Molecular Synthesis of Chinese Academy of Sciences Hefei 230026China

A highly regio-and enantioselective allylic C–H alkylation of 1,4-dienes with glycine Schiff bases has been established by chiral palladium-phosphoramidite catalysis. This reaction can proceed under mild conditions and tolerate a wide scope of 1,4-dienes,delivering structurally diverse chiral β-branched α-amino acid surrogates in moderate to high yields and with high levels of regio-, Z/E-, diastereo-and enantioselectivities.

关键词： asymmetric catalysis palladium allylic C–H alkylation 1,4-diene glycine Schiff base

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Access to chiral homoallylic vicinal diols from carbonyl allylation of aldehydes with allyl ethers via palladium-catalyzed allylic C-H borylation

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Science China Chemistry 2022年第2期65卷 298-303页

作者： Tian-Ci wang pu-sheng wang Dian-Feng Chen Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China Center for Excellence in Molecular Synthesis of CAS Hefei 230026China

Chiral homoallylic vicinal diols are found in many bioactive compounds and are among the most versatile functional groups in organic chemistry. Here, we describe an asymmetric carbonyl allylation of aldehydes with allyl ethers proceeding via allylic C-H borylation enabled by palladium and chiral phosphoric acid sequential catalysis, providing facile access to homoallylic vicinal anti-diols in high yields and with excellent stereoselectivity. This protocol enables the total synthesis of aigialomycin D to be finished within 7 steps.

关键词： asymmetric catalysis palladium allylic C–H borylation allyl ethers chiral phosphoric acid aldehydes

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Platinum-Catalyzed Allylic C-H Alkylation with Malononitriles

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CCS Chemistry 2022年第4期4卷 1366-1375页

作者： Lian-Feng Fan Pei-Pei Xie pu-sheng wang Xin Hong Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei 230026 Department of Chemistry Zhejiang UniversityHangzhou 310027 Center for Excellence in Molecular Synthesis of Chinese Academy of Sciences Hefei 230026

The direct functionalization of allylic C-H bonds is distinguished by enabling rapid assembly of structural complexity from simple *** Pd-catalyzed allylic C-H functionalization has been extensively studied,the discovery of new catalytic systems remains fairly ***,we disclose a Pt-catalyzed allylic C-H alkylation of a wide range of α-alkenes by using phosphoramidites as ligands and malononitriles as alkylating ***,the combination of chiral ureacatalyzed Michael addition and Pt-catalyzed allylic C-H alkylation can serve as an efficient protocol to access chiral tetrahydropyran with high levels of diastereo-and *** studies suggest that the Pt-catalyzed allylic C-H activation proceeds through a concerted proton and two-electron transfer process,which is analogous to transition state geometries of Pd catalysis.

关键词： platinum catalysis phosphoramidite C-H activation allylic alkylation concerted proton and two-electron transfer

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Chiral Anion Strategy For Asymmetry Allylic Alkylation

Chiral Anion Strategy For Asymmetry Allylic Alkylation

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手性中国2014学术研讨会

作者： pu-sheng wang Xiao-Le Zhou Hua-Chen Lin Liu-Zhu Gong Department of Chemistry University of Science and Technology of China

＜正＞Since the seminal reports by Tsuji and Trost on the palladium-catalyzed allylic alkylation,[1]this transformation has been accepted as one of the most significant carbon-carbon or carbon-heteroatom bond forming *** particular,the asymmetric version（AAA）has been a long term hot project receiving worldwide attention.[2]This reaction has eventually prompted the explosive development of chiral hgands and also led to the emergence of synthetically

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NFSI参与的高效铜催化苄位碳氢键烷氧基化反应

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中国科学技术大学学报 2023年第12期53卷 8-13,I0002,I0009页

作者：张铖汪普生中国科学技术大学化学系合肥微尺度物质科学国家研究中心安徽合肥230026

本文报道了一种铜催化苄位碳氢键烷氧基化反应,该反应在不需添加牺牲还原剂的条件下进行。机理研究揭示了从醋酸铜、N-氟代双苯磺酰胺和甲醇生成活性一价铜物种的新途径,其中适当用量的铜催化剂能够平衡苄位碳氢键烷氧基化反应和苄基醚... 详细信息

本文报道了一种铜催化苄位碳氢键烷氧基化反应,该反应在不需添加牺牲还原剂的条件下进行。机理研究揭示了从醋酸铜、N-氟代双苯磺酰胺和甲醇生成活性一价铜物种的新途径,其中适当用量的铜催化剂能够平衡苄位碳氢键烷氧基化反应和苄基醚产物过度氧化的反应速率,从而获得最佳收率。

关键词：碳氢活化氢原子转移烷氧基化醇铜自由基

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Nucleophile-Dependent Z/E-and Regioselectivity in the Palladium-Catalyzed Asymmetric Allylic C-H Alkylation of 1,4-Dienes

Nucleophile-Dependent Z/E-and Regioselectivity in the Pallad...

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中国化学会·第十三届全国物理有机化学学术会议

作者： Hua-Chen Lin Pei-Pei Xie Zhen-Yao Dai Shuo-Qing Zhang pu-sheng wang Yu-Gen Chen Tian-Ci wang Xin Hong Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Department of Chemistry Zhejiang University Collaborative Innovation Center of Chemical Science and Engineering

The asymmetric allylic alkylation（AAA）, which features employing active allylic substrates, has historical significance in organic synthesis. The allylic C-H alkylation is principally more atom-and step-economic than the classical allylic functionalizations and thus can be considered a transformative variant. However, asymmetric allylic C-H alkylation reactions are still scarce and yet underdeveloped. Herein, we have found that Z/E-and regioselectivities in the Pd-catalyzed asymmetric allylic C-H alkylation of 1,4-dienes are highly dependent on the type of nucleophiles. A highly stereoselective allylic C-H alkylation of 1,4-dienes with azlactones has been established by palladium-chiral phosphoramidite catalysis. The protocol proceeds under mild conditions and can accommodate a wide scope of substrates, delivering structurally divergent α,α-disubstituted α-amino acid surrogates in high yields and excellent levels of diastereo-, Z/E-, regio-, and enantioselectivities. Notably, this method provides key chiral intermediates for an efficient synthesis of lepadiformine marine alkaloids. Experimental and computational studies on the reaction mechanism suggest a novel concerted proton and two-electron transfer process for the allylic C-H cleavage and reveal that the Z/E-and regioselectivities are governed by the geometry and coordination pattern of nucleophiles.

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白内障超声乳化治疗闭角型青光眼的疗效

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国际眼科杂志 2012年第6期12卷 1160-1162页

作者：王普升魏成芳潘小燕张小隆盛迅伦宁夏自治区人民医院眼科

目的:评价白内障超声乳化联合人工晶状体植入治疗闭角型青光眼的适应证及临床效果。方法:回顾性分析合并有白内障的首发急性闭角型青光眼,且房角关闭粘连范围<180°的患者16例18眼,单纯行白内障超声乳化联合人工晶状体植入手术,观察分... 详细信息

目的:评价白内障超声乳化联合人工晶状体植入治疗闭角型青光眼的适应证及临床效果。方法:回顾性分析合并有白内障的首发急性闭角型青光眼,且房角关闭粘连范围<180°的患者16例18眼,单纯行白内障超声乳化联合人工晶状体植入手术,观察分析术前和术后眼压、前房深度、前房角及矫正视力的变化。结果:术后眼压全部控制在20mmHg(1mmHg=0.133kPa)以下,前房深度明显增加,17眼最佳矫正视力均有不同程度的提高,1眼无变化。术中、术后无严重手术并发症。术后随访期间,17眼视力无明显变化,1眼因视网膜分支静脉阻塞引起眼底出血视力下降明显。术前和术后眼压、前房深度、最佳矫正视力差异有统计学意义(P<0.05)。结论:恰当适应证的选择可使单纯超声乳化白内障治疗闭角型青光眼获得满意的临床效果。

关键词：超声乳化白内障闭角型青光眼

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Load Shedding Control Strategy in Power Grid Emergency State Based on Deep Reinforcement Learning

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1175-1182页

作者： Jian Li sheng Chen Xinying wang Tianjiao pu China Electric Power Research Institute Haidian DistrictBeijing 100192China

In viewing the power grid for large-scale new energy integration and power electrification of power grid equipment,the impact of power system faults is increased,and the ability of anti-disturbance is decreased,which makes the power system fault clearance more *** this paper,a load shedding control strategy based on artificial intelligence is proposed,this action strategy of load shedding,which is selected by deep reinforcement learning,can support autonomous voltage ***,the power system operation data is used as the basic data to construct the network training dataset,and then a novel reward function for voltage is *** value function,which conforms to the power grid operation characteristics,will act as the reward value for deep reinforcement learning,and the Deep Deterministic Policy Gradient algorithm(DDPG)algorithm,with the continuous action strategy,will be ***,the deep reinforcement learning network is continuously trained,and the load shedding strategy concerning the grid voltage control problem will be obtained in the power system emergency control situation,and this strategy action is input into the Pypower module for simulation verification,thereby realizing the joint drive of data and *** to the numerical simulation analysis,it shows that this method can effectively determine the accurate action selection of load shedding,and improve the stable operational ability of the power system.

关键词： Artificial intelligence deep reinforcement learning load shedding control power system emergency state

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