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Synthesis and Characterization of Osmium Polycyclic Aromatic Complexes via nucleophilic Reactions of Osmapentalyne

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Chinese Journal of Chemistry 2017年第5期35卷 628-634页

作者： Qin Zhu Congqing Zhu Zhihong Deng Guomei He Jiangxi Chen Jun Zhu Haiping Xia State Key Laboratory of Physical Chemistry of Solid Surfaces and Collaborative Innovation Center of Chemistry for Energy Materials ( iChEM) and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China Department of Materials Science and Engineering College of Materials Xiamen University Xiamen Fujian 361005 China

Treatment of osmapentalyne [Os { ≡C-C（COOMe）=CH-C =CH-C（PPh3） =CH-}Cl（PPh3）2]＋ BF4-with arylamines in the presence of Cs2CO3 produced osmium-bridged polycyclic aromatic *** this reaction,metal carbyne of osmapentalyne was first attacked by nucleophiles,followed by a C-H oxidative *** UV-Vis spectra of these osmium-bridged polycyclic aromatic complexes were *** result shows that these osmium-bridged polycyclic aromatic complexes have broad absorption in the UV-Vis region up to 650 nm.

关键词： metallapentalyne carbyne aromaticity nucleophilic C--H activation

Direct nucleophilic C-1 addition of stable isochromenylium tetrafluoroborates under catalyst-free conditions:A new access to 1H-isochromenes

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Science China Chemistry 2010年第4期53卷 869-876页

作者： HU ZhiLong, QIAN WenJian & YAO ZhuJun State Key Laboratory of Bioorganic and Natural Products Chemistry Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China State Key Laboratory of Bioorganic and Natural Products Chemistry Chinese Academy of Sciences Shanghai China Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai China

Direct additions of the stable isochromenylium tetrafluoroborates (ICTBs) were investigated with a number of readily available nucleophiles 2, yielding a variety of 1H-isochromenes 3 at low or mild temperatures withou... 详细信息

关键词： isochromenylium nucleophilic addition isochromene

Fluorescent probes for detection of biothiols based on “aromatic nucleophilic substitution-rearrangement” mechanism

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Chinese Chemical Letters 2019年第10期30卷 1791-1798页

作者： Yan-Fei Kang Li-Ya Niu Qing-Zheng Yang Hebei Key Laboratory of Quality&Safety Analysis-Testing for Agro-Products and Food and College of Laboratory MedicineHebei North UniversityZhangjiakou 075000China Key Laboratory of Radiopharmaceuticals Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China

Biothiols,including cysteine(Cys),homocysteine(Hey),and glutathione(GSH) play important roles in physiological processes,and the detection of thiol using fluorescent probes has attracted attention due to their high sensitivity and selectively and invasive on-time ***,the similar structures and reactivity of these biothiols present great challenges for selective *** review focused on the the "aromatic nucleophilic substitution-rearrangement(SNAr-rearrangement) mechanism",which provided a powerful tool to design fluorescent probes for the discrimination between *** classify the fluorescent probes according to types of fluorophores,such as difluoroboron dipyrromethene(BODIPY),nitrobenzoxadiazole(NBD),cyanine,pyronin,naphthalimide,coumarin,and so *** hope this review will inspire exploration of new fluorescent probes for biothiols and other relevant analytes.

关键词： Biothiols Fluorescent probes Aromatic nucleophilic substitution Rearrangement Fluorophores Bioapplication

Dechlorination of Crude Oil by Phase Transfer Catalyst via nucleophilic Substitution Reaction

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China Petroleum Processing & Petrochemical Technology 2021年第4期23卷 18-28页

作者： Gu Jin Han Xin Liu Jichang Huang Zihao Xing Biao State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237 Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan School of Chemistry and Chemical EngineeringShihezi UniversityShihezi 832003

Dechlorination of crude oil is an effective way to alleviate corrosion in refinery units,and the critical process is the removal of organochlorine which can be efficiently removed through nucleophilic substitution reaction catalyzed by phase ***,seven typical chlorinated alkanes were selected as model compounds to study the mechanism of dechlorination of crude oil by phase transfer catalyst in the nucleophilic substitution method,and a new dechlorination reagent using hexamethyl quaternary ammonium hydroxide(HMQAH)with two quaternary ammonium groups as phase transfer catalyst,ethylenediamine as nucleophile and ethanol as solvent was *** results show that the dechlorinating performance of the dechlorination reagent on the model compounds decreases in the following order:epichlorohydrin>1,2-dichlorobutane>1,2-dichloroethane>1,3-dichloropropane>2-chloropropane>1-chlorobutane>*** the results of the reaction kinetics show that epichlorohydrin with epoxy structure has the lowest activation energy in the process of nucleophilic substitution reaction by the phase transfer catalyst which makes it easier to be removed by the dechlorination *** removal rate of epichlorohydrin can reach up to 99.4%.The optimal dechlorination reagent used ethylenediamine as nucleophile,ethanol as solvent and HMQAH as phase transfer *** dechlorinating rate of the Iranian crude oil reached 71.6%under conditions covering a reaction temperature of 95℃,a reaction time of 90 minutes,a dechlorination reagent dosage of 1000μg/g,and a phase transfer reagent/nucleophile molar ratio of 6:*** addition,the mechanism of phase transfer in nucleophilic substitution reaction of chloroalkanes was investigated in the paper.

关键词： model compounds phase transfer nucleophilic substitution dechlorination Iranian crude oil

THE REDUCTION AND nucleophilic ADDITION OF MERCAPTOETHANOL TO HYPOCRELLIN A

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Chinese Science Bulletin 1992年第15期37卷 1274-1279页

作者：安静仪蒋丽金赵开弘 Institute of Photographic Chemistry Academia Sinica Beijing 100101 PRC

Ⅰ. INTRODUCTIONHypocrellin A （abbreviated as HA）is a perylenequinone derivative. The structure, ESR and absorption spectrum of the metastable product HAH2 produced by photoinduced net two-electron reduction of HA h... 详细信息

关键词： hypocrellin A mercaptoethanol reduction nucleophilic addition.

Difluoromethyl 2-Pyridyl Sulfoximine:A Stereoselective nucleophilic Reagent for Difluoro(aminosulfinyl)methylation and Difluoro(aminosulfonyl)methylation

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CCS Chemistry 2022年第11期4卷 3648-3659页

作者： Qinghe Liu Chuanfa Ni Qian Wang Depei Meng Jinbo Hu Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032

1,1-Difluorinated sulfonamides are known to have better anti-inflammatory activity and enzyme inhibitory potency than their nonfluorinated *** geminal fluorine atoms cause electronic perturbation of the nearby polar groups enhanced the biological activity of the 1,1-difluorinated ***,because methods for their stereoselective synthesis are scarce,such entities remain entirely ***,we outline an efficient method for the stereoselective introduction of the difluoro(aminosulfonyl)methyl group(CF_(2)SO_(2)NH_(2))into carbonyls,imines,and alkyl halides with a new(R)-2-pyridyl difluoromethyl sulfoximine reagent,which provides a unique solution for the synthesis of chiralα,α-difluorinated sulfonamides with a quaternary *** potency is illustrated by the synthesis of fluorinated analogues of bioactive compounds such as 2-OH-SA,an antagonist for the GABA_(B)receptor in guinea pig ileum,and the late-stage modification of complex molecules such as haloperidol,ebastine,cholesterol,and(+)-δ-tocopherol *** difluoro(aminosulfinyl)methylation to yield chiral sulfinylamides is presented,showcasing other uses of this new reagent.

关键词： difluoro(aminosulfonyl)methylation difluoro(aminosulfinyl)methylation stereoselective nucleophilic sulfoximine

Enantioselective　Synthesis　of　Amino　Acids　Based　on　nucleophilic　Reactions　of　Enolates

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合成化学 1996年第4期 325-337页

作者： Zhou,Chang-You (Department of Chemistry,Indiana University-Purdue University at Indianapolis Indianapolis,IN 46202,USA)

ＥｎａｎｔｉｏｓｅｌｅｃｔｉｖｅＳｙｎｔｈｅｓｉｓｏｆＡｍｉｎｏＡｃｉｄｓＢａｓｅｄｏｎＮｕｃｌｅｏｐｈｉｌｉｃＲｅａｃｔｉｏｎｓｏｆＥｎｏｌａｔｅｓＺｈｏｕ，Ｃｈａｎｇ－Ｙｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓ... 详细信息

ＥｎａｎｔｉｏｓｅｌｅｃｔｉｖｅＳｙｎｔｈｅｓｉｓｏｆＡｍｉｎｏＡｃｉｄｓＢａｓｅｄｏｎＮｕｃｌｅｏｐｈｉｌｉｃＲｅａｃｔｉｏｎｓｏｆＥｎｏｌａｔｅｓＺｈｏｕ，Ｃｈａｎｇ－Ｙｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＩｎｄｉａｎａＵｎｉｖｅｒ...

关键词： Amino Synthesis Based nucleophilic Acids

Computational Study for the Aromatic nucleophilic Substitution Reaction on 1-Dimethylamino-2,4-bis(trifluoroacetyl)-naphthalene with Amines

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International Journal of Organic Chemistry 2018年第3期8卷 273-281页

作者： Norio Ota Tomohiro Nakada Takumi Shintani Yasuhiro Kamitori Etsuji Okada Department of Chemical Science and Engineering Graduate School of Engineering Kobe University Kobe Japan

Our previous research showed that aliphatic amines were put in order of high reactivity as “ethylamine > ammonia > t-butylamine > diethylamine” on the aromatic nucleophilic substitution of 1-dimetylamino-2,4-bis(trifluoroacetyl)-naphthalene 1 in acetonitrile. The DFT calculation study (B3LYP/6-31G* with solvation model) for the reactions of 1 with above four amines rationally explained the difference of each amines reactivity based on the energies of their Meisenheimer complexes 3 which are assumed to formed as the reaction intermediates in the course of the reaction giving the corresponding N-N exchange products 2. Intramolecular hydrogen bond between amino proton in 1-amino group and carbonyl oxygen in 2-trifluoroacetyl group stabilizes Meisenheimer complexes 3 effectively, and accelerates the substitution reaction from 1 to 2. Our calculation results also predicted that the above order of amines is also true if less polar toluene is used as a solvent instead of acetonitrile even though more enhanced conditions are required.

关键词： 1-Amino-2 4-bis(trifluoroacetyl)naphthalenes Aliphatic Amines Meisenheimer Complexes Aromatic nucleophilic Substitution DFT Calculation

Effect of Cosolvent in a nucleophilic Substitution Reaction Using Organoclay in Triphase Catalytic System

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Modern Research in Catalysis 2015年第3期4卷 78-85页

作者： Nahid Shabestary Cynthia M. Chapple Derek T. Rensing Thao T. Doan Sadegh Khazaeli Michael J. Sabo Andrew D. Beach Department of Chemistry Southern Illinois University Edwardsville Edwardsville IL USA

A remarkable rate enhancement technique has been devised for a typical nucleophilic displacement reaction by using triphase catalytic materials based on tetraoctylammonium exchange forms of hectorite clay. Pseudo-first order rate constants (kobs) for the conversion of 1-bromobutane to the corresponding chloride under triphase conditions using the clay catalyst in the presence of various polar cosolvents have been observed. The results here have shown that the addition of a cosolvent increases the catalytic activity of the triphase system by several fold. In addition, the results have demonstrated that each cosolvent has a unique concentration for achieving an optimum reaction rate.

关键词： Triphase Catalysis Cosolvent Organoclay nucleophilic Displacement Reaction