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Synthesis of （Ph3P）2PdX2 Complexes and Their Catalytic Activity for Heck Reaction Involving Aryl Halide and Acrylate

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Chemical Research in Chinese Universities 2017年第6期33卷 860-863页

作者： liu Chengxin HAN Fangwai liu guiyan ZHAO Hongkun Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory of Inorganic-organic Hybrid Functional Material Chemistry(Tianfin Normal University) Ministry of Education College of Chemistry Tianjin Normal University Tianjin 300387 P. R. China

Two palladium complexes, （Ph3P）2PdBr2 and （PhsP）2PdI2, were synthesized by a new method and their structures were confirmed by NMR, elemental analysis and X-ray crystallography. The catalytic activity of the two palladium complexes was evaluated in Mizoroki-Heck cross-coupling reaction of aryl halide with acrylate, and the results show that they all have high catalytic activity to many different substrates.

关键词： Palladium catalyst Triphenylphosphine ligand Mizoroki-Heck reaction

Synthesis and Catalytic Activity of a Grubbs-Hoveyda Pre-catalyst Having a Trimeric Resting State

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Chinese Journal of Chemistry 2015年第4期33卷 441-445页

作者： guiyan liu Bin Wu Jianhui Wang Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry(Tianjin Normal University)Ministry of EducationCollege of ChemistryTianjin Normal UniversityTianjin 300387China Department of Chemistry College of ScienceTianjin UniversityTianjin 300072China

A Grubbs-Hoveyda pre-catalyst having a trimeric resting state based on 2,4,6-trichloro-1,3,5-triazine was syn-thesized and the complex was characterized by NMR,HRMS and elemental *** activity of this complex for ring-closing metathesis(RCM)was *** catalytic system possesses high catalytic activity for many different olefin substrates.

关键词： olefin metathesis ruthenium carbene catalyst

Synthesis of Quinoline and 1,2,3,4-Tetrahydroquinoline Derivatives from Substituted o-Nitrotoluenes via Cesium-promoted [2＋4] Cycloaddition

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Chinese Journal of Chemistry 2017年第10期35卷 1569-1574页

作者： Weijie Guo Maocong Yi Jianhui Wang guiyan liu Department of Chemistry School of Science Tianjin University Tianjin 300072 China Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory ofInorganic-Organic Hybrid Functional Material Chemistry Ministry of Education College of Chemistry Tianjin Normal University Tianjin 300387 China

An atom economical highly efficient method has been developed for the synthesis of quinoline and 1,2,3,4-tetra- hydroquinoline derivatives from o-nitrotoluenes bearing electron-withdrawing groups and olefins （acrylic esters, acrylonitriles, and methyl acrylates） via a base-catalyzed [2＋4] cycloaddition. This simple, rapid, and environment- friendly method provides a practical pathway for the synthesis of quinoline and 1,2,3,4-tetrahydroquinoline derivatives. The starting materials are readily available and 37 products were obtained in good to excellent yields.

关键词： quinoline 1,2,3,4-tetrahydroquinoline cesium cycloaddition

Long-term trend analysis of wave characteristics in the Bohai Sea based on interpolated ERA5 wave reanalysis from 1950 to 2020

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Acta Oceanologica Sinica 2022年第7期41卷 97-112页

作者： Jichao Wang Peidong Sun Zhihong Liao Fan Bi guiyan liu College of Science China University of PetroleumQingdao266580China National Meteorological Information Center Beijing100081China North China Sea Marine Forecasting Center of State Oceanic Administration Qingdao266061China Shandong Provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao266061China

Reasonably understanding of the long-term wave characteristics is very crucial for the ocean engineering.A feedforward neural network is operated for interpolating ERA5 wave reanalysis in this study,which embodies a detailed record from 1950 *** spatiotemporal variability of wave parameters in the Bohai Sea,especially the significant wave height(SWH),is presented in terms of combined wave,wind wave and swell by employing the 71 years(1950–2020)of interpolated ERA5 *** mean SWH decreases at−0.12 cm/a estimated by Theil-Sen estimator and 95th percentile SWH reflecting serve sea states decreases at−0.20 cm/***-seasonal analysis shows SWH of wind wave has steeper decreasing trend with higher slopes than that of swell,especially in summer and winter,showing the major decrease may attribute to the weakening of *** inner Bohai Sea reveals a general decreasing trend while the intersection connecting with the Yellow Sea has the lower significance derived by Mann-Kendall ***,95th percentile SWH decreases at a higher rate while with a lower significance in comparison with the mean *** frequencies of mean wave directions in sub-sector are statistically calculated to find the seasonal prevailing ***,the dominant directions in summer and winter are south and north.A similar variation concerning to SWH,the trend of the mean wave period is provided,which also shows a decrease for decades.

关键词： wave characteristic wind wave swell long-term trend Bohai Sea

Synthesis and Catalytic Study of Ruthenium Carbene Catalyst Containing a Zn-Porphyrin Ligand

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Chinese Journal of Chemistry 2015年第12期33卷 1393-1397页

作者： Ying Xu Huizhu Zhang Xinyuan Wang guiyan liu Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry(Tianjin Normal University)Ministry of Education College of Chemistry Tianjin Normal UniversityTianjin300387China

A ruthenium carbene complex containing a Zn-porphyrin ligand has been developed. The complex was charac- terized by 1H NMR, IR, HRMS and elemental analysis. The catalytic activity of the ruthenium carbene complex for olefin metathesis reactions was also investigated. The complex exhibited excellent performance for both ring-closing and cross metathesis reactions at 35 ℃.

关键词： olefin metathesis ruthenium carbene catalyst Zn-porphyrin

N-Heterocyclic Carbene Copper(Ⅰ)Complex Catalyzed Coupling of(Hetero)aryl Chlorides and Nitrogen Heterocycles:Highly Efficient Catalytic System

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Chinese Journal of Chemistry 2020年第11期38卷 1252-1256页

作者： Mengyao Zhang Yingying Zhang Huixin Zhang Yongfei Zeng guiyan liu Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry(Tianjin Normal University)Ministry of EducationCollege of ChemistryTianjin Normal UniversityTianjin 300387China

of main observation and conclusion A highly efficient catalytic system for the N-arylation reactions of(hetero)aryl chlorides and nitrogen heterocycles with a copper(l)complex containing a 1,10-phenanthroline analogue N-heterocyclic carbene(NHC)has been *** complex was characterized by^lH NMR and^13C NMR spectroscopy and elemental analysis,and its structure was determined by single-crystal X-ray *** NHC-copper(l)complex was employed as pre-catalyst for Ullmann type N-arylation reactions of(hetero)aryl chlorides with various azoles.A variety of hindered and functionalized azoles and(hetero)aryl chlorides were transformed in good to excellent yields.

关键词： diffraction. copper Catalytic

A forecasting model for wave heights based on a long short-term memory neural network

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Acta Oceanologica Sinica 2021年第1期40卷 62-69页

作者： Song Gao Juan Huang Yaru Li guiyan liu Fan Bi Zhipeng Bai North China Sea Marine Forecasting Center of State Oceanic Administration Qingdao 266061China Shandong Provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao 266061China Mailbox 5111 Beijing 100094China

To explore new operational forecasting methods of waves,a forecasting model for wave heights at three stations in the Bohai Sea has been *** model is based on long short-term memory(LSTM)neural network with sea surface wind and wave heights as training *** prediction performance of the model is evaluated,and the error analysis shows that when using the same set of numerically predicted sea surface wind as input,the prediction error produced by the proposed LSTM model at Sta.N01 is 20%,18%and 23%lower than the conventional numerical wave models in terms of the total root mean square error(RMSE),scatter index(SI)and mean absolute error(MAE),***,for significant wave height in the range of 3–5 m,the prediction accuracy of the LSTM model is improved the most remarkably,with RMSE,SI and MAE all decreasing by 24%.It is also evident that the numbers of hidden neurons,the numbers of buoys used and the time length of training samples all have impact on the prediction ***,the prediction does not necessary improve with the increase of number of hidden neurons or number of buoys *** experiment trained by data with the longest time length is found to perform the best overall compared to other experiments with a shorter time length for ***,long short-term memory neural network was proved to be a very promising method for future development and applications in wave forecasting.

关键词： long short-term memory marine forecast neural network significant wave height

Highly Active Pd-PEPPSI Complexes for Suzuki-Miyaura Cross-coupling of Aryl Chlorides:an Investigation on the Effect of Electronic Properties

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Chemical Research in Chinese Universities 2020年第5期36卷 859-864页

作者： ZHANG Yingying HAN Fangwai ZHANG Mengvao ZHANG Huixin LI Ying WANG Ru ZENG Yongfei liu guiyan Tianjin Key Laboratory of Stmcture and Performance for Functional Molecules Key Laboratory of Inorganic-organic Hybrid Functional Material ChemistryMinistry of EducationCollege of ChemistryTianjin Normal UniversityTianjin 300387P.R.China

Three new Pd-pyridine enlianced precatalyst preparation stabilization and initiation(PEPPSI)complexes with halogen groups on the N-heterocyclic carbene and pyridine were *** structures have been clearly characterized by nuclear magnetic resonance spectroscopy and X-ray single-crystal di *** e fleets of the electronic properties of halogen groups on the catalytic activity in the Suzuki-Miyaura cross-coupling of aryl chlo-rides were *** Pd-PEPPSI complexes could catalyze the cross-coupling reaction efficiently with a low catalyst loading(0.05%,molar ratio)at room temperature and the products were obtained in high yields.

关键词： Pd-pyridine enhanced precatalyst preparation stabilization and initiation(PEPPSI)complex Suzuki-Miyaura cross-coupling reaction Aryl chloride

Construction of a Three-dimensional Covalent Organic Framework via the Linker Exchange Strategy

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Chemical Research in Chinese Universities 2022年第2期38卷 402-408页

作者： CUI Yumeng MIAO Zhuang liu Qi JIN Fenchun ZHAI Yufeng ZHANG Lingyan WANG Wenli WANG Ke liu guiyan ZENG Yongfei Tianjin Key Laboratory of Structure and Performance for Functional Molecules College of ChemistryTianjin Normal UniversityTianjin 300387P.R.China

Covalent organic framework(COF)is a porous crystalline material with a well-controlled structure and a wide range of potential ***,the construction of new COF faces huge challenges,including the design and synthesis of structural unit monomers,the choice of reaction solvent system,and the study of reaction time and ***,it’s particularly important to widen the application scope of synthetic methods and further promote the development of ***,we performed structural transformations in a three-dimensional(3D)COF(COF-300),and Fourier transform infrared spectroscopy(FTIR),power X-ray diffraction analysis(PXRD)and nitrogen adsorption isotherms confirmed the chemical principles and the successful realization of these *** the same time,we found that the interpenetrating structure in 3D COF can be changed through the conversion of *** structure simulation successfully proved the transformation of COF from five-fold to seven-fold *** addition,in order to prove the versatility of this strategy,we used the same method to convert COF-300 into a high crystallinity 3D COF(TJNU-COF-302)that is also seven-fold interpenetrating and has not been *** simple strategy not only makes it easy to obtain a 3D COF connected with imines,which greatly promotes the development of COF,but also provides a new way to develop 3D COFs with complex interpenetrating structures.

关键词： Covalent organic framework(COF) Linker exchange Transformation strategy Porosity