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Redox potentials of trifluoromethyl-containing compounds

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Science China Chemistry 2015年第4期58卷 673-683页

作者： yuanye Jiang haizhu yu Yao Fu Lei Liu Department of Chemistry University of Science and Technology of China Department of Polymer Science and Engineering University of Science and Technology Beijing Department of Chemistry Tsinghua University

Trifluoromethylation reactions are important transformations in the research and development of drugs, agrochemicals and functional materials. An oxidation/reduction process of trifluoromethyl-containing compounds is thought to be involved in many recently tested catalytic trifluoromethylation reactions. To provide helpful physical chemical data for mechanistic studies on trifluoromethylation reactions, the redox potentials of a variety of trifluoromethyl-containing compounds and trifluoro- methylated radicals were studied by quantum-chemical methods. First, eoB97X-D was found to be a reliable method in predicting the ionization potentials, electron affinities, bond dissociation enthalpies and redox potentials of trifluoromethylcontaining compounds. One-electron absolute redox potentials of 79 trifluoromethyl substrates and 107 trifluoromethylated radicals in acetonitrile were then calculated with this method. The theoretical results were found to be helpful for interpreting experimental observations such as the relative reaction efficiency of different trifluoromethylation reagents. Finally, the bond dissociation free energies （BDFE） of various compounds were found to have a good linear relationship with the related bond dissociation enthalpies （BDE）. Based on this observation, a convenient method was proposed to predict one-electron redox potentials of neutral molecules.

关键词： trifluoromethylation redox potential density functional theory

Mechanism of the Ir/Pd catalyzed photocarboxylation of aryl halides

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Chinese Chemical Letters 2021年第4期32卷 1403-1406页

作者： Ying Lv Bing Wang haizhu yu Department of Chemistry and Centre for Atomic Engineering of Advanced Materials Anhui University.Hefei 230601China Department of Chemistry University of Science and Technology of ChinaHefei 230026China

The recent Ir/Pd co-catalyzed photo carboxylation of aromatic halides with CO_(2) has shown high efficiency and excellent functional group tolerance for preparing aromatic carboxylic acids and *** the aid of density functional theory(DFT)calculations,the carboxylation starts with two parallel steps,i.e.,oxidative addition of aromatic halides on Pd~0 and reductive quenching of the photocatalyst Ir(ppy)_(2)(dtbpy)~+with ***,a successive oxidation of Pd~Ⅱwith the amine radical(generated by the reaction of cationic radical amine and Cs_(2) CO_(3)and Ir~Ⅱspecies occurs to generate Pd~0,from which the carboxylation occurs easily via a coordination,Pd-C insertion *** release of the carboxylate product then regenerates the catalyst.

关键词： Carboxylation Pd-catalysis DFT Charge state Mechanism

A mechanistic study on the regioselective Ni-catalyzed methylation–alkenylation of alkyne with AlMe3 and allylic alcohol

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Organic Chemistry Frontiers 2022年第1期9卷 163-172页

作者： Jiao Liu Deguang Liu Wan Nie haizhu yu Jing Shi Hefei National Laboratory for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyDepartment of ChemistryUniversity of Science and Technology of ChinaHefeiAnhui 230026China Department of Chemistry Anhui UniversityHefeiAnhui 230026China

The recently reported Ni-catalyzed methylation–allylation of alkynes with allylic alcohols and AlMe3 reagents delivers valuable tetrasubstituted alkene units in a highly regioselective *** by the experimental significance and the mechanistic ambiguity(*** details of C–O bond activation,the function of the Lewis acid AlMe3,etc.),we conducted a detailed mechanistic study using density functional theory(DFT)*** reaction was found to occur via the C–O bond activation of allylic alcohol,allylation of alkyne,transmetalation,reductive elimination and catalyst regeneration ***3 could easily react with the allylic alcohol to form a cyclodialuminoxane species bearing two groups of Lewis acid–base *** this regard,the C(allyl)–O bond is remarkably activated,resulting in a relatively facile C–O activation(compared to the typical Lewis-acid mediated reactions).In addition,the Al–Me interaction is a double-edged sword to the methylation step:the cyclodialuminoxane group functions as the methyl resource,while the full dissociation of the Al–Me interaction(via a cis-to-trans isomerization)is a requisite to fully release the methyl *** this context,the“Me-relay”pathway involving the[Ni]–Me intermediate is found to be more plausible than all other mechanistic possibilities(such as the typical concerted Me-transfer mechanism in previous studies).

关键词： alcohol catalyzed allyl

Accurate Prediction of Au--P Bond Strengths by Density Functional Theory Methodst

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Chinese Journal of Chemistry 2013年第2期31卷 200-208页

作者： haizhu yu Dingjia Liu Zhimin Dang Dongrui Wang Yao Fu Department of Polymer Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Chemistry University of Science and Technology of China Hefei Anhui 230026 China

The recent development of Au-catalyzed reactions has greatly enriched the methods of organic synthesis. The phosphine or phosphate-coordinated Au complexes have shown high efficiency in catalyzing various C--C and C-- H activations. In many of these reactions, the Au--P bond strength was found to play an important role in deter- mining the catalytic efficiency. In the present study, the accuracy of different theoretical methods for prediction of Au--P strengths has been examined on basis of the experimental enthalpy changes between different CIAu（PR3） and C1Au（THT）（THT----tetrahydrothiophene）. By comparing the different DFT functionals （e.g. B3LYP, TPSS, M06）, different basis sets （including the different effective core potentials on Au and the total electron basis sets on all other atoms）, and different solution phase single point calculations, we found that the TPSS/（CPE-121G＋f： 6-311 ＋G（d,p）（SMD）//TPSS/（CPE-121G：6-31G（d）（M1） method gives the best correlations with the available experimental results. Meanwhile, the calculations with B3LYP//TPSS and MOS//TPSS also give comparable calculation results. Finally, the specified method （M1） is used to calculate the Au--P bond dissociation enthalpies and energies of different C1Au（PR3）/CIAu（P（OR）3） complexes. By accurately reproducing the available experimental results, we believe that the method （M1） is reliable for the theoretical analysis of Au-P systems.

关键词： DFT Au--P BDE phosphine phosphate

Accurate Prediction of Ir-H Bond Dissociation Enthalpies by Density Functional Theory Methods

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Chinese Journal of Chemistry 2014年第3期32卷 269-275页

作者： Yi Zhou Dingjia Liu Yao Fu haizhu yu Jing Shi Department of Polymer Science and Engineering University of Science and Technology BeijingBeijing 100083China Department of Chemistry University of Science and Technology of ChinaHefeiAnhui 230026China

The iridium hydride complexes have been extensively used in organic reactions,such as oxidation and hydro-genation *** many of these reactions,the dissociation or formation of Ir-H bond plays an important role in determining the overall reaction rates and *** the present study,the accuracy of different theoretical meth-ods for prediction of Ir-H bond strengths has been examined on the basis of the previously reported Ir-H BDEs of 17 different *** the performance of different DFT functionals(e.g.B3LYP,TPSS,M06),different basis sets(including the different effective core potentials(ECP)on Ir and I atoms,and the total electron basis sets on the other atoms),and different solvation models(SMD,CPCM,and IEFPCM)in solution phase single point calculations,we found that the gas-phase calculation with TPSS/(LanL2DZ:6-31G(d))method is relatively more accurate than the other gas-phase calculation methods,and can well simulate the Ir-H BDEs in low-polarity solvents(such as chlorobenzene and dichloroethane).Finally,efforts were put in analyzing the structure-activity re-lationships between the ligand structure(around Ir center)and the Ir-H *** wish the present study could benefit future studies on the Ir-H complexes involved organic reactions.

关键词： density functional theory Ir-H bond dissociation enthalpy

A bright two-photon fluorescent probe for real-time monitoring autophagy in living cells

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Chinese Chemical Letters 2020年第2期31卷 447-450页

作者： Chuankun Jiang Longchun Li Jiacheng Jiang Lilin Hou Gemin Fang haizhu yu Xiangming Meng School of Chemistry and Chemical Engineering Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materialsand Institute of Physical Science and Information TechnologyAnhui UniversityHefei 230601China Department of Applied Chemistry School of scienceAnhui Agricultural UniversityHefei 230036China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China

A novel donor-acceptor(D-A) type of two-photon(TP) fluorescent probe,***-OSC,based on the lysosome-targeting morpholine group was *** polarity sensing coumarin group was functionalized as the acceptor and the 1-vinyl-4-methoxybenzene group was engineered as the *** fluorescence intensity and emission maximum wavelength of Lyso-OSC are highly sensitive to the polarity changes of *** two-photon absorption cross-section and tissue penetration depth are up to 254 GM and 150 μm,*** strong fluorescence,high sensitivity to polarity,low cytotoxicity,and accurate lysosome-targeting ability entail Lyso-OSC the excellent performance in detecting the polarity changes ofcellular *** this end,a bright,real-time imaging autophagy of living cells has been achieved.

关键词： Two-photon Lysosome-targeting Polarity Real-time Autophagy

Nicotinamide adenine dinucleotide(NAD^(+))reduction enabled by an atomically precise Au-Ag alloy nanocluster

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Nano Research 2023年第5期16卷 7770-7776页

作者： Ling Chen Yonglei Du Ying Lv Daoqing Fan Junfei Wu Lingbao Wu Mengting Cui haizhu yu Manzhou Zhu Department of Chemistry and Centre for Atomic Engineering of Advanced Materials Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Physical Science and Information Technology and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsAnhui UniversityHefei 230601China Institute of Energy Hefei Comprehensive National Science CenterHefei 230601China

The redox property of the ultrasmall coinage nanoclusters(with several to tens of Au/Ag atoms)has elucidated the electrontransfer capacity of nanoclusters,has been successfully utilized in a variety of redox conversions(such as from CO_(2)to CO).Nevertheless,their biological applications are mainly restricted by the scarcity of atomically precise,water-soluble metal nanoclusters,the limited application(mainly on the decomposition of H_(2)O_(2)in these days).Herein,mercaptosuccinic acid(MSA)protected ultrasmall alloy AuAg nanoclusters were prepared,the main product was determined[Au_(3)Ag_(5)(MSA)_(3)]−by electrospray ionization mass spectrometry(ESI-MS).The clusters can not only mediate the decomposition of H_(2)O_(2)to generate hydroxyl radicals,but is also able to mediate the reduction of nicotinamide adenine dinucleotide(NAD)to its reduced form of *** is the first time that the atomically precise metal nanoclusters were used to mediate the coenzyme *** preliminary mechanistic insights imply the reaction to be driven by the hydrogen bonding between the carboxylic groups(on the surface of MSA)and the amino N–H bonds(on NAD).In this context,the presence of the carboxylic groups,the sub-nanometer size regime(~1 nm),the synergistic effect of the Au-Ag clusters are pre-requisite to the NAD reduction.

关键词： redox-activity alloy AuAg nanocluster nicotinamide adenine dinucleotide(NAD)reduction synergistic effect size-effect

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拒马河干流典型场次暴雨洪水对比分析

北京水务 2024年第2期 1-6页

作者：于海柱季明锋苟璐峰龚义新北京市水文总站北京100089

为了明确拒马河干流典型场次暴雨洪水情况,通过研究拒马河流域紫荆关和张坊的水文数据,结合相关气象背景资料,从降雨和洪水两方面对“7·21”和“23·7”暴雨洪水特征进行对比分析,结果表明:因“7·21”和“23·7”降雨特点不同,导致拒... 详细信息

为了明确拒马河干流典型场次暴雨洪水情况,通过研究拒马河流域紫荆关和张坊的水文数据,结合相关气象背景资料,从降雨和洪水两方面对“7·21”和“23·7”暴雨洪水特征进行对比分析,结果表明:因“7·21”和“23·7”降雨特点不同,导致拒马河流域洪水呈现出不同的特点;2场降雨中紫荆关—张坊区间产流量均高于紫荆关上游流域;受降雨时空分布差异影响,“7·21”洪水中紫荆关和张坊断面流量过程均呈现单峰形状,“23·7”洪水中两站则呈现多峰形状,且“7·21”洪水涨落速度快于“23·7”洪水。此研究为今后更好开展拒马河流域水旱灾害防御工作提供参考。

关键词：大清河 “7·21”暴雨 “23·7”暴雨洪水拒马河张坊紫荆关

Secondary ligand engineering of nanoclusters:Effects on molecular structures,supramolecular aggregates,and optical properties

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聚集体(英文)

聚集体(英文) 2023年第1期4卷 277-284页

作者： Xiao Wei Ying Lv Honglei Shen Hao Li Xi Kang haizhu yu Manzhou Zhu Department of Chemistry and Centre for Atomic Engineering of Advanced Materials Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationInstitutes of Physical Science and Information Technology and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsAnhui UniversityHefeiChina

Developing new templates to evaluate the ligand engineering effect in manipulating nanoclusters from both molecular and supramolecular aspects remains highly desired in cluster science because it allows for an in-depth understanding of structure-property *** herein presented the secondary ligand(i.e.,the phosphine ligand)engineering based on an Ag_(29) nanocluster template and its dual effects on intracluster structures and intercluster ***“dissociationcombination equilibrium”of phosphine ligands on the nanocluster surface was controlled by tailoring the C-H…πinteractions within the ligand shell,which led to the fabrication of a family of[Ag_(29)(BDT)_(12)(PR_(3))_(x)]^(3-)*** the molecular level,the dissociation of phosphine ligands contracted the nanocluster framework,while the overall configuration of[Ag_(29)(BDT)_(12)]^(3-)was *** the supramolecular level,the complete dissociation of phosphine ligands yielded a bare nanocluster,which followed a chiral crystallization mode,and its crystals displayed high optical activity,derived from circular dichroism and circularly polarized luminescence ***,this work presents the peripheral ligand effects in directionally controlling intracluster configurations and intercluster aggregations,which hopefully benefit future design and preparation of new nanoclusters or cluster-based nanomaterials with customized structures and performances.

关键词： precise nanocluster ligand engineering molecular structure supramolecular aggregate optical property