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CCS Chemistry 2022年第12期4卷 3693-3704页

作者： Cheng-Feng Gao Yin Zhou Hai Ma Yue Zhang Jing Nie Fa-Guang Zhang Jun-An Ma Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic SciencesFrontiers Science Center for Synthetic BiologyMinistry of EducationTianjin Collaborative Innovation Centre of Chemical Science and EngineeringTianjin UniversityTianjin 300072 Institute of Chinese Materia Medica China Academy of Chinese Medical SciencesBeijing 100700

The dual incorporation of two important functional groups—trifluoromethyl and cyano moieties into one heterocyclic core in a single-step reaction represents an appealing but largely unaddressed synthetic challenge.Here we demonstrate that a silver-catalyzed[3+2]cycloaddition reaction of dicyanoalkenes with trifluorodiazoethane(CF_(3)CHN2)could render a facile construction of a unique category of pyrazoles that are simultaneously adorned by trifluoromethyl and cyano groups.Changing the location pattern of the cyano group in starting dicyanoalkene material allows regiodivergent access to two series of previously elusive trifluoromethyl cyanopyrazoles with an exquisite level of regiocontrol.Thus,this method could be applied in the preparation of cyano-analogues of CF_(3)-containing drugs(Celecoxib)and agrochemicals(Penthiopyrad and Fluazolate).Notably,several cyano-analogues of Celecoxib demonstrate enhanced inhibitory activity towards cyclooxygenase-2(COX-2),thereby laying a good foundation for developing new lead-based antiinflammatory agents.

关键词： pyrazoles trifluoromethyl group cyano group silver catalysis diazo reagents

Upgrading CO2 by Incorporation into Urethanes through silver-Catalyzed One-Pot Stepwise Amidation Reaction

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Chinese Journal of Chemistry 2018年第2期36卷 147-152页

作者： Qing-Wen Soog Ping Liu Li-Hua Han Kan Zhang Liang-Nian He State Key Laboratory of Coal Conversion Institute of Coat Chemistry Chinese Academy of Sciences Taiyuan Shanxi 030001 China State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

One-pot two-step stepwise reaction of terminal propargylic alcohols, carbon dioxide, and primary/secondary amines for the effective synthesis of various urethanes through robust silver-catalysed C-O/C-N bond formation is reported, Catalytic activities were investigated by controlling catalyst loading, reaction pressure and time, and very high turnover number （turnover frequency） was obtained： 3350 （35 h-1） with 0.01 mol% silver catalyst under 0.1 MPa, and up to 13360 （139 h-1） with 0.005 mol% silver catalyst under 2.0 MPa at room temperature. The strategy was ingeniously regulated, and synchronously afforded a wide range of β-oxopropylcarbamate and 1,3-oxazolidin-2-one motifs in excellent yields and selectivity together with unprecedented high turnover number （TON） and turnover frequency （TOF） value.

关键词： carbon dioxide utilization homogeneous catalysis C-N bond formation silver catalysis synthetic method

Access to multi-functionalized oxazolines via silver-catalyzed heteroannulation of enamides with sulfoxonium ylides

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Chinese Chemical Letters 2021年第4期32卷 1411-1414页

作者： Rui-Hua Liu Qi-Chao Shan Ya Gao Teck-Peng Loh Xu-Hong Hu Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing 211816China Division of Chemistry and Biological Chemistry School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore

Disclosed herein is an efficient Ag-catalyzed 4+1 heteroannulation reaction of enamides withα-carbonyl sulfoxonium ylides.The diastereoselective transformation provides a practical access to a diverse range of multi-functionalized oxazoline derivatives.The synthetic utility of the resultant tetrasubstituted oxazolines is further demonstrated by a series of useful manipulations into valuable building blocks of pharmaceutical relevance.

关键词： Enamides Sulfoxonium ylides Oxazolines silver catalysis Heteroannulation

Synthesis of dimeric butenolide catalyzed by various inorganic silver catalysts

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Traditional Medicine Research 2023年第6期8卷 33-38页

作者： Ruo-Meng Wei Qian-Qian Liu Ying Li Wen-Jiao Yan Xiao-Ru Zhang Ai-Qin Liu School of Pharmacy and Pharmaceutical Sciences Shandong First Medical UniversityJinan 250117China Institute of Materia Medica Shandong Academy of Medical SciencesJinan 250117China NHC Key Laboratory of Biotechnology Drugs(Shandong Academy of Medical Sciences) Jinan 250117China Key Lab for Rare&Uncommon Diseases of Shandong Province Jinan 250117China Department of Neurology Liaocheng Third People’s HospitalLiaocheng 252000China

This article describes a method for synthesizing butyrolactone dimers using various inorganic silver salt catalysts.The method was successfully applied to alkyl 2-(2-bromopropyl)malonate 1,providing the dimeric butyrolactone 2 when catalyzed by different silver salt catalysts.This synthesis method not only simplifies the original synthetic route,but also cleverly combines with natural product analogs,providing a strategy for the development of natural product polymer analogs in the future.

关键词： Mikania sesquiterpenes dimer toxicology silver catalysis

silver-catalyzed Reactions of Isocyanides

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Silver-catalyzed Reactions of Isocyanides

中国化学会第十三届全国有机合成化学学术研讨会

作者： Liu Jian-Quan Bi Xi-He Department of Chemistry Northeast Normal University

In the last years,we have carried out the studies on the silver-catalyzed reactions of isocyanides,and discovered a series of novel reactions,including the cyclization of alkynes and isocyanides,the cross-coupling reactions between isocyanides and active methylene compounds or alcohols.These studies have provided novel and convenient methods for synthesizing important compounds such as pyrroles,1 benzoheteroles,2 allenamides,3 β-aminoenones,4 and carbamates.5 More importantly,silver salts displayed unique catalysis activities in these reactions.In addition,most of the reactions proceeded through radical mechanism.These results demonstrate the uniqueness of combining silver catalysis and isocyanide chemistry,which should be useful for designing and developing silver-based reactions of isocyanides.

关键词： silver catalysis isocyanides radical reaction heterocycles

silver-Catalyzed C-to N-Center Radical Remote Arene Migration of Alkynes

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Silver-Catalyzed C-to N-Center Radical Remote Arene Migratio...

中国化学会·第十五届全国有机合成化学学术研讨会

作者： Yongquan Ning 毕锡和 Department of Chemistry Northeast Normal University 东北师范大学

The development of selective C–C bond cleavage processes has been attracting much attention in organic synthesis.Significant advances have been achieved on the selective functionalization of C-C bonds in both strained and unstrained molecules, and migrations between carbon centers by transfer of functional groups to proximal carbon-centered radicals, cations, and carbenes have become well-established. Among these, significant progress has been reported for radical-mediated group migrations between carbon centers using unsaturated substrates. Mechanistically, a common reaction pathway is observed involving initiation of the reaction by radical addition to the unsaturated systems to generate a C-radical intermediate, which proceed through radical ipso substitution followed by C-C cleavage(Figure 1a).However, there have been no studies on aryl migration from carbon to a nitrogen center using unsaturated substrates, probably due to the lack of versatile radical initiation methods to produce N-center radicals, and indeed carbon-to-nitrogen remote aryl migration is rare in general. Building on our interests in silver-catalyzed alkyne activation, we report herein a mild, silver-catalyzed C-center to N-center radical-mediated remote arene migration reaction of homopropargylic alcohols, employing TMSN as the nitrogen atom source, and sodium sulfinates as radical generators(Figure 1b).To the best of our knowledge, this is the first example of aryl migration from C-to N-center using alkynes as substrates.

关键词： silver catalysis arene migration radical alkynes N-center

silver-Catalyzed σ-Activation of Terminal Alkynes

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Silver-Catalyzed σ-Activation of Terminal Alkynes

中国化学会第十四届全国有机合成化学学术研讨会

作者： Yongquan Ning Jianquan Liu Xihe Bi Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis Northeast Normal University

The innovation in synthetic methodologies, in terms of selectivity, availability of starting materials, functional-group tolerance, operational simplicity and environmental sustainability, is fundamental to the art of organic synthesis. Transition-metal catalysis significantly contributes to the development of organic chemistry in the past few decades. Coinage metals including gold, silver and copper exhibited impressive catalytic activities in organic synthesis. Unlike the traditional studies on copper catalysis and the "Gold Rush" over the past decade, silver salts have long been considered to possess low catalytic efficiency and most typically they are used as either co-catalysts or Lewis acids. In the past years, silver catalysis has been emerging as an active field in the frontier of organic synthesis, especially its unique catalytic activity continue to be discovered, which provides the opportunity for the innovation in synthetic methodologies. In the last years, we have carried out the studies on the silver-catalyzed σ-activation of terminal alkynes, and discovered a series of novel organic reactions. Herein, we wish to present these interesting results to the organic chemical community.

关键词： terminal alkynes silver catalysis σ-activation

silver-Catalyzed Activation and Reactions of Organic Molecules

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Silver-Catalyzed Activation and Reactions of Organic Molecul...

中国化学会·第十六届全国有机合成化学学术研讨会

作者： Zhaohong Liu 毕锡和 Department of Chemistry Northeast Normal University 东北师范大学

The innovation in synthetic methodologies,in terms of selectivity,availability of starting materials,functional-group tolerance,operational simplicity and environmental sustainability,is fundamental to the art of organic synthesis.Transition-metal catalysis significantly promoted the development of organic chemistry in the past decades.Gold,silver,and copper,so-called "coinage metals",exhibit interesting catalytic activities in organic synthesis. Unlike the traditional studies on copper catalysis and the recent "Gold Rush",silver salts have long been considered to possess low catalytic efficiency and most typically they are used as either co-catalysts or Lewis acids.In the last years,silver catalysis has been emerging as an active field in the frontier of organic synthesis,especially,its unique catalytic activity displayed in many reactions. Our research group has been focused on silver catalysis in organic synthesis for many years. Here,we wish to present the research results in this direction by the activation of organic compounds,including terminal alkynes,isocyanides,and diazo compounds,by silver salts through the formation of corresponding organosilver species such as silver acetylides, isocyanide silver,ad and silver carbenoides. These results demonstrate silver is a robust catalyst for these three kinds of chemicals.

关键词： silver catalysis activation reaction organic molecules