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Trifluoromethylthiolation and Trifluoromethylselenolation of α‐Diazo Esters Catalyzed by Copper 下载免费PDF全文
Christian Matheis Prof. Dr. Lukas J. Goossen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12270-12273
α‐Diazo esters are smoothly converted into the corresponding trifluoromethyl thio‐ or selenoethers by reaction with Me4NSCF3 or Me4NSeCF3, respectively, in the presence of catalytic amounts of copper thiocyanate. This straightforward method gives high yields under neutral conditions at room temperature and is applicable to a wide range of functionalized molecules, including diverse α‐amino acid derivatives. It is well‐suited for the late‐stage introduction of trifluoromethylthio or ‐seleno groups into drug‐like molecules. 相似文献
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A Copper(I)‐Catalyzed Enantioselective γ‐Boryl Substitution of Trifluoromethyl‐Substituted Alkenes: Synthesis of Enantioenriched γ,γ‐gem‐Difluoroallylboronates 下载免费PDF全文
Dr. Ryoto Kojima Sota Akiyama Prof. Dr. Hajime Ito 《Angewandte Chemie (International ed. in English)》2018,57(24):7196-7199
The first catalytic enantioselective γ‐boryl substitution of CF3‐substituted alkenes is reported. A series of CF3‐substituted alkenes was treated with a diboron reagent in the presence of a copper(I)/Josiphos catalyst to afford the corresponding optically active γ,γ‐gem‐difluoroallylboronates in high enantioselectivity. The thus obtained products could be readily converted into the corresponding difluoromethylene‐containing homoallylic alcohols using highly stereospecific allylation reactions. 相似文献
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Synthesis of α‐Aryl Esters and Nitriles: Deaminative Coupling of α‐Aminoesters and α‐Aminoacetonitriles with Arylboronic Acids 下载免费PDF全文
Guojiao Wu Yifan Deng Chaoqiang Wu Dr. Yan Zhang Prof. Dr. Jianbo Wang 《Angewandte Chemie (International ed. in English)》2014,53(39):10510-10514
Transition‐metal‐free synthesis of α‐aryl esters and nitriles using arylboronic acids with α‐aminoesters and α‐aminoacetonitriles, respectively, as the starting materials has been developed. The reaction represents a rare case of converting C(sp3)? N bonds into C(sp3)? C(sp2) bonds. The reaction conditions are mild, demonstrate good functional‐group tolerance, and can be scaled up. 相似文献
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Jiang Wu Yang Gu Dr. Xuebing Leng Prof. Dr. Qilong Shen 《Angewandte Chemie (International ed. in English)》2015,54(26):7648-7652
An efficient copper‐promoted difluoromethylthiolation of aryl and heteroaryl diazonium salts is described. The reaction is conducted under mild reaction conditions and various functional groups were compatible. In addition, reactions of heteroaryl diazonium salts such as pyridyl, quinolinyl, benzothiazolyl, thiophenyl, carbazolyl, and pyrazolyl diazonium salts occurred smoothly to afford the medicinally important difluoromethylthiolated heteroarenes. Furthermore, a more practical one‐pot direct diazotization and difluoromethylthiolation protocol was developed, and it converts the aniline derivatives into difluoromethylthiolated arenes. The utility of the method is demonstrated by difluoromethylthiolation of a number of natural products and drug molecules. 相似文献
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Copper‐Catalyzed Intermolecular Trifluoromethylazidation of Alkenes: Convenient Access to CF3‐Containing Alkyl Azides 下载免费PDF全文
Fei Wang Xiaoxu Qi Zhaoli Liang Dr. Pinhong Chen Prof. Dr. Guosheng Liu 《Angewandte Chemie (International ed. in English)》2014,53(7):1881-1886
A novel copper‐catalyzed intermolecular trifluoromethylazidation of alkenes has been developed under mild reaction conditions. A variety of CF3‐containing organoazides were directly synthesized from a wide range of olefins, including activated and unactivated alkenes, and the resulting products can be easily transformed into the corresponding CF3‐containing amine derivatives. 相似文献
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Naijing Su Juliana A. Theorell Prof. Dr. Donald J. Wink Prof. Dr. Tom G. Driver 《Angewandte Chemie (International ed. in English)》2015,54(44):12942-12946
The combination of 20 mol % of copper iodide and lithium tert‐butoxide triggers the formation of a broad range of substituted, functionalized α‐alkoxy 2H‐naphthalenones from readily available N‐tosylhydrazones. The data suggests that this transformation occurs through cycloaddition of a copper carbenoid with an ester, followed by a Lewis acid‐catalyzed [1,2] alkyl shift of the in situ generated alkoxyepoxide intermediate. 相似文献
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Activation of α‐Diazocarbonyls by Organic Catalysts: Diazo Group Acting as a Strong N‐Terminal Electrophile 下载免费PDF全文
Lei Li Jia‐Jia Chen Yi‐Jin Li Xiu‐Bin Bu Qun Liu Yu‐Long Zhao 《Angewandte Chemie (International ed. in English)》2015,54(41):12107-12111
For the first time α‐diazocarbonyls have been used as highly active N‐terminal electrophiles in the presence of bicyclic amidine catalysts. The C? N bond‐forming reactions of active methylene compounds as C nucleophiles with α‐diazocarbonyls as N‐terminal electrophiles proceed quickly under ambient conditions, in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU), because of the formation of the reactive N‐terminal electrophilic intermediates. DBU activates both the active methylene and α‐diazocarbonyl. Importantly, this reaction is general for both active methylenes and α‐diazocarbonyls, and the activation mode will lead to new synthetic applications of α‐diazocarbonyls. 相似文献
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Copper Salt‐Controlled Divergent Reactivity of [Cu]CF2PO(OEt)2 with α‐Diazocarbonyl Derivatives 下载免费PDF全文
Dr. Tatiana Besset Prof. Dr. Xavier Pannecoucke Dr. Thomas Poisson 《Angewandte Chemie (International ed. in English)》2016,55(45):14141-14145
Herein, we report a copper salt‐controlled divergent reactivity toward α‐diazocarbonyl compounds. By a simple change of the copper counteranion under identical reaction conditions, the reported method allowed an easy access to either (Z)‐α‐fluorovinylphosphonate or alkyl‐SCF2PO(OEt)2 derivatives in good yields. Mechanistic studies were performed and suggested two different pathways to explain the formation of these products. 相似文献
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Direct Access to α,α‐Difluoroacylated Arenes by Palladium‐Catalyzed Carbonylation of (Hetero)Aryl Boronic Acid Derivatives 下载免费PDF全文
Thomas L. Andersen Mette W. Frederiksen Katrine Domino Prof. Dr. Troels Skrydstrup 《Angewandte Chemie (International ed. in English)》2016,55(35):10396-10400
A palladium‐catalyzed carbonylative coupling of (hetero)aryl boronates or boronic acid salts with carbon monoxide and α‐bromo‐α,α‐difluoroamides and bromo‐α,α‐difluoroesters is described herein. The method is useful for the synthesis of a diverse selection of (hetero)aryl α,α‐difluoro‐β‐ketoamides and α,α‐difluoro‐β‐ketoesters, which are useful building blocks for the generation of functionalized difluoroacylated and difluoroalkyl arenes. The method could be further extended to a one‐pot protocol for the formation of difluoroacetophenones. 相似文献
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Gang Li Tao Wang Fan Fei Dr. Yi‐Ming Su Dr. Yan Li Dr. Quan Lan Prof. Dr. Xi‐Sheng Wang 《Angewandte Chemie (International ed. in English)》2016,55(10):3491-3495
The first example of nickel‐catalyzed decarboxylative fluoroalkylation of α,β‐unsaturated carboxylic acids has been developed with commonly available fluoroalkyl halides. This novel transformation has demonstrated broad substrate scope, excellent functional‐group tolerance, mild reaction conditions, and excellent stereoselectivity. Mechanistic investigations indicate that a fluoroalkyl radical is involved in the catalytic cycle. 相似文献
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Sophie I. Arlow Prof. John F. Hartwig 《Angewandte Chemie (International ed. in English)》2016,55(14):4567-4572
A copper‐catalyzed coupling of aryl, heteroaryl, and vinyl iodides with α‐silyldifluoroamides is reported. The reaction forms α,α‐difluoro‐α‐aryl amides from electron‐rich, electron‐poor, and sterically hindered aryl iodides in high yield and tolerates a variety of functional groups. The aryldifluoroamide products can be transformed further to provide access to a diverse array of difluoroalkylarenes, including compounds of potential biological interest. 相似文献