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Chao Shu Long Li Cang‐Hai Shen Peng‐Peng Ruan Chao‐Yue Liu Prof. Dr. Long‐Wu Ye 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(7):2282-2290
Two new gold‐catalyzed tandem cycloisomerization–halogenation reactions of chiral homopropargyl sulfonamides have been developed. Various enantioenriched 3,3‐diiodopyrrolidin‐2‐ols and 3‐fluoropyrrolidin‐2‐ols were obtained in moderate‐to‐good yields with excellent enantio‐ and diastereoselectivity. 相似文献
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Zhuo Xin Dr. Søren Kramer Dr. Jacob Overgaard Prof. Dr. Troels Skrydstrup 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(26):7926-7930
A new synthetic route to the privileged 1,2‐dihydroisoquinolines is reported. This method, which relies on a gold‐catalyzed formal [4+2] cycloaddition between ynamides and imines, provides a new retrosynthetic disconnection of the 1,2‐dihydroisoquinoline core by installing the 1,8a C?C and 2,3 C?N bonds in one step. Both aldimines and ketimines can be used as substrates. In addition, one example of dihydrofuropyridine synthesis is also demonstrated. 相似文献
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Diversity in Gold‐Catalyzed Formal Cycloadditions of Ynamides with Azidoalkenes or 2H‐Azirines: [3+2] versus [4+3] Cycloadditions 下载免费PDF全文
Samir Kundlik Pawar Rajkumar Lalji Sahani Prof. Dr. Rai‐Shung Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(30):10843-10850
Gold‐catalyzed cycloadditions of ynamides with azidoalkenes or 2H‐azirines give [3+2] or [4+3] formal cycloadducts of three classes. Cycloadditions of ynamides with 2H‐azirine species afford pyrrole products with two regioselectivities when the Cβ‐substituted 2H‐azirine is replaced from an alkyl (or hydrogen) with an ester group. For ynamides substituted with an electron‐rich phenyl group, their reactions with azidoalkenes proceed through novel [4+3] cycloadditions to deliver 1H‐benzo[d]azepine products instead. 相似文献
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Regiocontrolled Gold‐Catalyzed [2+2+2] Cycloadditions of Ynamides with Two Discrete Nitriles to Construct 4‐Aminopyrimidine Cores 下载免费PDF全文
Somnath Narayan Karad Prof. Dr. Rai‐Shung Liu 《Angewandte Chemie (International ed. in English)》2014,53(34):9072-9076
Reported herein is the novel gold‐catalyzed intermolecular [2+2+2] cycloaddition of ynamides with two discrete nitriles to form monomeric 4‐aminopyrimidines, which are pharmaceutically important structural motifs. The utility of this new cycloaddition is demonstrated by the excellent regioselectivity obtained using a variety of ynamides and nitriles. 相似文献
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Amit Kumar Sukhdev Singh Sunil K. Sharma Virinder S. Parmar Erik V. Van der Eycken 《Chemical record (New York, N.Y.)》2016,16(1):73-83
Over the years, gold catalysis has materialized as an incredible synthetic approach among the scientific community. Due to the trivial reaction conditions and great functional compatibility, these progressions are synthetically expedient, because practitioners can implement them to build intricate architectures from readily amassed building blocks with high bond forming indices. The incendiary growth of gold catalysts in organic synthesis has been demonstrated as one of the most prevailing soft Lewis acids for electrophilic activation of carbon‐carbon multiple bonds towards a great assortment of nucleophiles. Nowadays, organic chemists consistently employ gold catalysts to carry out a diverse array of organic transformations to build unprecedented molecular architectures. Despite all these achievements and a plethora of reports, many vital challenges remain. In this account, we describe the reactivity of various gold catalysts towards cyclization processes developed over the years. These protocols give access to a wide scope of polyheterocyclic structures, containing different medium‐sized ring skeletons. This is interesting, as the quest for highly selective reactions to assemble diversely functionalized products has attracted much attention. We envisage that these newly developed chemo‐, regio‐, and diastereoselective protocols could provide an expedient route to architecturally cumbersome heterocycles of importance for the pharmaceutical industry. 相似文献
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Gold‐Catalyzed 6‐Exo‐Dig Cycloisomerization: A Versatile Approach to Functionalized Phenanthrenes 下载免费PDF全文
A novel gold‐catalyzed 6‐exo‐dig cycloisomerization of o‐propargylbiaryls has been developed that provides ready access to functionalized phenanthrenes in largely good to excellent yields. Notable features of this method are readily available starting materials, mild reaction conditions, and broad substrate scope. 相似文献
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Gold‐Catalyzed Ring Expansion of Alkynyl Heterocycles through 1,2‐Migration of an Endocyclic Carbon–Heteroatom Bond 下载免费PDF全文
Ming Chen Ning Sun Wei Xu Jidong Zhao Gaonan Wang Prof. Yuanhong Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(51):18571-18575
A mild and efficient gold‐catalyzed oxidative ring‐expansion of a series of alkynyl heterocycles using pyridine‐N‐oxide as the oxidant has been developed, which affords highly valuable six‐ or seven‐membered heterocycles with wide functional group toleration. The reaction consists of a regioselective oxidation and a chemoselective migration of an endocyclic carbon–heteroatom bond (favored over C?H migration) with the order of migratory aptitude for carbon–heteroatom bonds being C?S>C?N>C?O. In the absence of an oxidant, polycyclic products are readily constructed through a ring‐expansion/Nazarov cyclization reaction sequence. 相似文献
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Gold‐Catalyzed Oxidative Ring Expansion of 2‐Alkynyl‐1,2‐Dihydropyridines or ‐quinolines: Highly Efficient Synthesis of Functionalized Azepine or Benzazepine Scaffolds 下载免费PDF全文
Ming Chen Dr. Yifeng Chen Ning Sun Jidong Zhao Prof. Yuanhong Liu Prof. Yuxue Li 《Angewandte Chemie (International ed. in English)》2015,54(4):1200-1204
A gold‐catalyzed highly regio‐ and chemoselective oxidative ring expansion of 2‐alkynyl‐1,2‐dihydropyridines and its analogues using pyridine‐N‐oxide as the oxidant has been developed. Ring expansion proceeds through exclusive 1,2‐migration of a vinyl or phenyl group, whereas no 1,2‐H and 1,2‐N migration take place. The reaction provides an efficient and attractive route to various types of medium‐sized azepine derivatives in generally high to excellent yields with a broad functional group tolerance. DFT studies indicate that the reaction proceeds through the formation of a cyclopropyl gold intermediate, and no gold carbene species is involved. 相似文献
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Gold(I)‐Catalyzed Selective Heterocyclization of Propargylic Thioureas: Mechanistic Study of Competitive Gold‐Activation Mode 下载免费PDF全文
Yu Jiang Dr. Yin Wei Prof. Dr. Xiang‐Ying Tang Prof. Dr. Min Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7675-7681
A new selective gold(I)‐catalyzed intramolecular heterocyclization of propargylic thioureas has been developed, efficiently affording two kinds of cycloadducts in moderate to excellent yields with a broad substrate scope. Further mechanistic investigations indicate that competitive different gold activation modes feature in these cyclization processes. Kinetic experiments reveal that the gold activation mode is influenced by the ligand of the gold catalyst and the reaction conditions. 相似文献
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Haipeng Hu Yangbin Liu Dr. Lili Lin Yuheng Zhang Prof. Dr. Xiaohua Liu Prof. Dr. Xiaoming Feng 《Angewandte Chemie (International ed. in English)》2016,55(34):10098-10101
Highly efficient kinetic resolution of 2H‐azirines by an asymmetric imine amidation was achieved in the presence of a chiral N,N′‐dioxide/ScIII complex, thus providing a promising method to obtain the enantioenriched 2H‐azirine derivatives and protecting‐group free aziridines at the same time. It is rare to find an example of N1 of an oxindole participating in a reaction over C3. Moreover, chiral 2H‐azirines were stereospecifically transformed into an unprotected aziridine and α‐amino ketone. 相似文献
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Gold‐Catalyzed Cascade Reactions for Synthesis of Carbo‐ and Heterocycles: Selectivity and Diversity
This account describes our recent efforts devoted to gold chemistry since 2009. Based on furyl–Au 1,3‐dipole analogues and related gold carbene intermediates, a rich variety of gold‐catalyzed cascade reactions have been developed, which provide facile access to a diverse range of novel carbo‐ and heterocycles. In these reactions, the selectivity can be well controlled by the catalyst (ligand and metal), substrate or reagent. In addition, we have also developed the corresponding enantioselective variants, which are guided by bis(phosphinegold) complexes derived from axially chiral scaffolds and asymmetric gold/chiral Brønsted acid relay catalysis. 相似文献
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Gold‐Catalyzed Cascade Cyclization of 2‐Alkynyl‐N‐Propargylanilines by Rearrangement of a Propargyl Group 下载免费PDF全文
Yusuke Tokimizu Dr. Shinya Oishi Prof. Dr. Nobutaka Fujii Prof. Dr. Hiroaki Ohno 《Angewandte Chemie (International ed. in English)》2015,54(27):7862-7866
Gold catalysis enables direct construction of tetracyclic fused indolines through the migration of a propargyl substituent from an aniline nitrogen atom to the C3‐position of an indole from 2‐alkynyl‐N‐propargylanilines. This reaction provides rapid access to fused three‐dimensional indolines in a single operation with the formation of four bonds and three rings. 相似文献
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Jacob C. Timmerman Bradley D. Robertson Prof. Ross A. Widenhoefer 《Angewandte Chemie (International ed. in English)》2015,54(7):2251-2254
The cationic gold phosphine complex [{PCy2(o‐biphenyl)}Au(NCMe)]+SbF6? (Cy=cyclohexyl) catalyzes the intermolecular, anti‐Markovnikov hydroamination reaction of monosubstituted and cis‐ and trans‐disubstituted alkylidenecyclopropanes (ACPs) with imidazolidin‐2‐ones and other nucleophiles. This reaction forms 1‐cyclopropyl alkylamine derivatives in high yield and with high regio‐ and diastereoselectivity. NMR spectroscopic analysis of gold π‐ACP complexes and control experiments point to the sp hybridization of the ACP internal alkene carbon atom as controlling the regiochemistry of the ACP hydroamination reaction. 相似文献
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Atom‐Economic Synthesis of Fully Substituted 2‐Aminopyrroles via Gold‐Catalyzed Formal [3+2] Cycloaddition between Ynamides and Isoxazoles 下载免费PDF全文
Xin‐Yu Xiao Ai‐Hua Zhou Chao Shu Fei Pan Dr. Ting Li Prof. Dr. Long‐Wu Ye 《化学:亚洲杂志》2015,10(9):1854-1858
A concise and flexible synthesis of fully substituted 2‐aminopyrroles via gold‐catalyzed formal [3+2] cycloaddition between ynamides and isoxazoles has been developed. Under mild reaction conditions, various 2‐aminopyrrole derivatives were obtained in good to excellent yields, thus providing an efficient and atom‐economic way for the construction of fully substituted 2‐aminopyrroles. 相似文献