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Science China Chemistry 2009年第12期52卷 2195-2199页

作者： LIU ChunYan1,2 & JIANG ShenDe1 1 School of Pharmaceutical Science and Technology,Tianjin University,Tianjin 300072,China 2 Department of Pharmacy,North China Coal Medical College,Tangshan 063000,China School of Pharmaceutical Science and Technology Tianjin University Tianjin China Department of Pharmacy North China Coal Medical College Tangshan China

Two novel triflate precursors for radiolabelling of L-tyrosine in positron emission tomography (PET) for tumor imaging,O-(2-trifluoromethanesulfonyloxyethyl)-N-(tert-butoxycarbonyl)-L-tyrosine methyl ester 9a and O-(2-trifluoromethanesulfonyloxyethyl)-N-(tert-butoxycarbonyl)-L-tyrosine tert-butyl ester 9b,are synthesized. The triflate agent,9a or 9b,is prepared by esterification of methanol or transesterification of tert-butyl acetate with L-tyrosine,protection of the amine group with di-tert-butyl dicarbonate,alkylation with chlorohydrin,and triflation with trifluoromethanesulfonic anhydride in four steps with overall yields of 30% and 15%,respectively.

关键词： positron emission tomography triflate L-tyrosine [18F]FET precursor PET imaging

Highly-Efficient Conversion of Primary Amides to Nitriles Using Indium(III) triflate as the Catalyst

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International Journal of Organic Chemistry 2014年第1期4卷 1-6页

作者： Tomoko Mineno Mamika Shinada Kazuki Watanabe Hitoshi Yoshimitsu Hiroyuki Miyashita Hisao Kansui Laboratory of Medicinal Chemistry Faculty of Pharmacy Takasaki University of Health and Welfare Takasaki Japan Laboratory of Natural Medicines Faculty of Pharmaceutical Sciences Sojo University Kumamoto Japan Laboratory of Organic Chemistry for Life Sciences Faculty of Pharmacy Takasaki University of Health and Welfare Takasaki Japan Laboratory of Organic Chemistry Faculty of Pharmaceutical Sciences Sojo University Kumamoto Japan

Indium(III) triflate, a trivalent indium reagent, was shown to be a highly-efficient catalyst for the conversion of primary amides to the corresponding nitriles. The successful reactions required 5 mol% of indium(III) triflate, and toluene was proved to be the most suitable solvent. Various amides were subjected to this method, and each produced the corresponding nitriles in excellent yields.

关键词： Indium(III) triflate Primary Amides Nitriles

Oxone-Mediated Oxidative Esterification of Heterocyclic Aldehydes Using Indium(III) triflate

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Green and Sustainable Chemistry 2014年第1期4卷 20-23页

作者： Tomoko Mineno Saki Yoshino Akira Ubukata aboratory of Medicinal Chemistry Faculty of Pharmacy Takasaki University of Health and Welfare Takasaki Japan Laboratory of Medicinal Chemistry Faculty of Pharmacy Takasaki University of Health and Welfare Takasaki Japan

Recent investigations have shown the oxone-mediated oxidative methyl esterification of benzaldehyde derivatives using methanol. The reactions were accelerated in the presence of indium(III) triflate, a trivalent indium reagent, in many cases. Based on this method of methyl esterification of benzaldehyde derivatives, we further explored an application to heterocyclic aldehydes. The reactions were examined using methanol as well as other alcohols in order to establish a suitable range.

关键词： Oxidative Esterification Heterocyclic Aldehydes Indium(III) triflate

Facile and Efficient Method for Synthesis of Benzimidazole Derivatives Catalyzed by Zinc triflate

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Green and Sustainable Chemistry 2014年第1期4卷 33-37页

作者： Ramineni Srinivasulu Kannasani Ravi Kumar Peruri Veera Venkata Satyanarayana Chalapathi Institute of Engineering and Technology Department of chemistry Guntur India Department of Chemistry Acharya Nagarjuna University Guntur India RA Chem Pharma Limited R&D Division Prasanth Nagar Hyderabad India

We report the synthesis of benzimidazole derivatives using zinc triflate as an efficient catalyst. One-pot synthesis of 2-substituted benzimidazole derivatives from o-phynelyenediamine and substituted aldehydes were d... 详细信息

关键词： Benzimidazole Derivatives O-Phynelyenediamine Substituted Aldehydes Zinc triflate

Dehydrosulfurization of Aromatic Thioamides to Nitriles Using Indium(III) triflate

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International Journal of Organic Chemistry 2014年第3期4卷 169-173页

作者： Tomoko Mineno Yu Takebe Chiaki Tanaka Sho Mashimo Laboratory of Medicinal Chemistry Faculty of Pharmacy Takasaki University of Health and Welfare Takasaki Gunma Japan

The efficient dehydrosulfurization of thioamides to nitriles was carried out using indium(III) triflate as a catalyst. Based on the results of the initial study, the optimal reaction conditions required 5 mol% of indium(III) triflate with toluene as the practical solvent. Various thioamides were successfully converted to nitriles in high yields.

关键词： Indium(III) triflate Dehydrosulfurization Thioamide Nitriles

A Novel Initiator Containing Alkyne Group for the Polymerization of 2-Ethyl-2-oxazoline

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Chinese Journal of Chemical Physics 2018年第1期31卷 77-84,I0002页

作者： Muhammad Waqas Ali 高亚婷 Muhammad Siddiq 叶晓东中国科学技术大学化学物理系、合肥微尺度物质科学国家研究中心合肥230026 中国科学技术大学、中国科学院软物质化学重点实验室合肥230026 巴基斯坦真纳大学化学系伊斯兰堡453201

A novel trifunctional initiator with one alkyne and two trifluoromethanesulfonate moieties was synthesized from a protected alcohol 5-hydroxyl-2-phenyl-1, 3-dioxane. The alkyne func- tionalized intermediate with two protected alcohol groups was synthesized by reacting with propargyl bromide. The alcohol groups were cleaved using a mixture of tetrahydrofuran and hydrochloric acid aqueous solution. In the last step the initiator was synthesized us- ing triflic anhydride in carbon tetrachloride. The initiator was characterized by 1H NMR and used for the polymerization of 2-ethyl-2-oxazoline which gives polymers with narrow distribution. For comparison a similar initiator with two tosylates was prepared and used for the polymerization of the monomer 2-ethyl-2-oxazoline, the resulting product has a wide molecular weight distribution and most of the initiator remains unreacted after 24 h which may be due to the steric hindrance between the two tosylate groups. To further explore the steric hindrance phenomenon, a linear tosylate initiator was synthesized, but still some of the initiator remains unreacted, illustrating that both steric hindrance and electrophilic balance affect the efficiency of the cationic ring-opening polymerization. All of the polymers were characterized in detail by using IH NMR, matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy, and size exclusion chromatography to confirm the purity and distribution of the polymers.

关键词： Electrophile 2-Ethyl-2-oxazoline Steric hindrance triflate

Recent progress in lantha-nide-catalyzed organic reactions in protic media

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Chinese Science Bulletin 2001年第20期46卷 1673-1681页

作者： LUO Sanzhong ZHANG Baolian XIAN Ming Adam Janczuk XIE Wenhua CHENG Jinpei Peng George Wang Department of Chemistry Nankai UniversityTianjin 300071China Department of Chemistry Wayne State UniversityDetroit MI 48202-3489USA

Lanthanide triflates are stable in water. It is possible for lanthanides to undergo many organic reactions in environmentally friendly solvents. This makes lanthanides very promising in the field of green chemistry. This review describes the recent development of the lanthanide-catalyzed organic reactions in protic solvents. Those reac-tions include Diels-Alder, Aldol, Allylation, acetalization, pericyclization, radical reactions as well as some newly-developed lanthnides-based catalysts.

关键词： green chemistry lanthanide triflate aqueous media organic syntheses.

Elucidation of Acceleration Mechanisms by a Photosensitive Onium Salt for Nitroxide-Mediated Photocontrolled/Living Radical Polymerization

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Open Journal of Polymer Chemistry 2014年第3期4卷 47-55页

作者： Eri Yoshida Department of Environmental and Life Sciences Toyohashi University of Technology Toyohashi Japan

The acceleration mechanisms by a photosensitive onium salt for the nitroxide-mediated photocontrolled/living radical polymerization (photo-NMP) were determined. The photo-NMP of methyl methacrylate was performed by irradiation at room temperature using 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl (MTEMPO) as the mediator and (2RS, 2’RS)-azobis(4-methoxy-2,4-dimethylvaleronitrile) as the initiator. The polymerization was accelerated in the presence of (4-tertbutylphenyl)diphenylsulfonium triflate (tBuS) to produce a polymer with a molecular weight distribution as narrow as the polymerization in its absence. (±)-Camphor-10-sulfonic acid or 2-fluoro-1-methylpyridinium p-toluenesulfonate had no effect on the polymerization speed, suggesting that tBuS did not serve as the photo-acid generator for the photo-NMP. It was found that the acceleration of the polymerization was based on the electron transfer from MTEMPO into tBuS in the excited state to temporarily generate a free radical propagating chain end and an oxoaminium salt (OAS), the one-electron oxidant of MTEMPO. This electron transfer mechanism was verified on the basis of the fact that the photo-NMP in the presence of tBuS was still accelerated by triphenylamine, the electron transfer inhibitor, to partly produce a polymer with an uncontrolled molecular weight. The formation of an uncontrolled molecular weight polymer indicated the generation of a free radical propagating chain end due to the deactivation of the OAS by the triphenylamine. It was deduced that tBuS served as the electron acceptor from MTEMPO in the excited state to temporarily produce a free radical propagating chain end along with OAS, resulting in the acceleration of the polymerization.

关键词： Photocontrolled/Living Radical Polymerization Acceleration Mechanisms Electron Transfer (4-tert-Butylphenyl)Diphenylsulfonium triflate 4-Methoxy-2 2 6 6-Tetramethylpiperidine-1-Oxyl Oxoaminium Salt

Nitroxide-Mediated Photo-Controlled/Living Radical Polymerization of Methacrylic Acid

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Open Journal of Polymer Chemistry 2013年第1期3卷 16-22页

作者： Eri Yoshida 不详

The photo-controlled/living radical polymerization of methacrylic acid (MAA) was performed at room temperature by irradiation with a high-pressure mercury lamp using azo initiators and 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl as the mediator in the presence of (4-tert-butylphenyl)diphenylsulfonium triflate (tBuS) as the accelerator. Whereas the bulk polymerization yielded polymers with a bimodal molecular weight distribution in both the absence and presence of tBuS, the solution polymerization in methanol produced unimodal polymers with the molecular weight distribution of 2.0 - 2.3 in the presence of tBuS. The molecular weight distribution of the resulting poly (MAA) decreased with an in- crease in tBuS. The dilution of the monomer concentration also reduced the molecular weight distribution. The use of the initiator with a low 10-h half-life temperature also effectively controlled the molecular weight. The livingness of the polymerization was confirmed by obtaining linear increases in the first-order conversion versus time, the molecular weight versus the conversion, and the molecular weight versus the reciprocal of the initiator concentration.

关键词： Photo-Controlled/Living Radical Polymerization Nitroxide-Mediated Polymerization Methacrylic Acid 4-Methoxy-2 2 6 6-Tetramethylpiperidine-1-Oxyl (4-Tert-butylphenyl)diphenylsulfonium triflate Molecular Weight Control

Effect of Added Cu(OTf)2on the Cu(OTf)2(Py)4-Mediated Radiofluorination of Benzoyl and Phthaloylglycinates

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Natural Science 2018年第3期10卷 125-133页

作者： David W. Blevins George W. Kabalka Dustin R. Osborne Murthy R. Akula Department of Radiology University of Tennessee Medical Center Knoxville Tennessee USA Department of Chemistry University of Tennessee Knoxville Tennessee USA

Cu(OTf)2(Py)4 mediated radiofluorination of the boronate esters of ethyl benzoyl and phthaloylglycinates (11 and 16) using 10 mol% of the copper complex following the literature procedure did not provide the fluorinated products. However, the addition of Cu(OTf)2resulted in the radio-fluorination of the boronate esters 11 and 16 to obtain ethyl 4-[18F]fluorobenzoyl glycinate, 17, (48%) and ethyl 3-[18F]phthaloylglycinate (41%) respectively.

关键词： Glycinates Boronate Esters Gorlos-Phos Radiofluorination Copper triflate