Highly Substituted Lactone/Ester-Containing Furan Library by the Palladium-Catalyzed Carbonylation of Hydroxyl-Substituted 3-Iodofurans
摘要:
Highly substituted lactone- and ester-containing furans have been prepared by the efficient palladium-catalyzed intramolecular cyclocarbonylation or intermolecular carboalkoxylation, respectively, of hydroxyl-containing 3-iodofurans, readily prepared by the iodocyclization of 2(1-alkynyl)-2-alken-1-ones in the presence of various diols.
Synthesis of Highly Substituted Furans by the Electrophile-Induced Coupling of 2-(1-Alkynyl)-2-alken-1-ones and Nucleophiles
作者:Tuanli Yao、Xiaoxia Zhang、Richard C. Larock
DOI:10.1021/jo0510585
日期:2005.9.1
induced by an electrophile, provides highlysubstitutedfurans in good to excellent yields under very mild reaction conditions. Various nucleophiles, including functionally substitutedalcohols, H2O, carboxylic acids, 1,3-diketones, and electron-rich arenes, and a range of cyclic and acyclic 2-(1-alkynyl)-2-alken-1-ones readily participate in these cyclizations. Iodine, NIS, and PhSeCl have proven
Paracyclophane-based Silver Phosphates as Catalysts for Enantioselective Cycloisomerization/Addition Reactions: Synthesis of Bicyclic Furans
作者:Guillaume Force、Yvette Lock Toy Ki、Kévin Isaac、Pascal Retailleau、Angela Marinetti、Jean-François Betzer
DOI:10.1002/adsc.201800587
日期:2018.9.3
C2‐symmetric paracyclophane scaffolds as chiral counterions in transition metal catalysis, showing that they may compare favorably with other known chiral phosphates, such as the TRIP phosphate. The targeted catalyticreaction is a silver(I) promoted domino heterocyclization of 2‐(1‐alkynyl)‐2‐alken‐1‐one derivatives, in the presence of C‐, or N‐nucleophiles, which provides an efficient access to substituted bicyclic
A novel cascade reaction has been developed for the synthesis of 2,6‐methanopyrrolo[1,2‐b]isoxazoles based on the gold‐catalyzed generation of an N‐allyloxyazomethine ylide. This reaction involves sequential [3+2]/retro‐[3+2]/[3+2] cycloaddition reactions, thus providing facile access to fused and bridged heterocycles which would be otherwise difficult to prepare using existing synthetic methods. Notably
Mechanism of a No-Metal-Added Heterocycloisomerization of Alkynylcyclopropylhydrazones: Synthesis of Cycloheptane-Fused Aminopyrroles Facilitated by Copper Salts at Trace Loadings
作者:Sidney M. Wilkerson-Hill、Diana Yu、Phillip P. Painter、Ethan L. Fisher、Dean J. Tantillo、Richmond Sarpong、Jason E. Hein
DOI:10.1021/jacs.7b06007
日期:2017.8.2
heterocycloisomerization reaction that forms annulated aminopyrroles is presented. Density functional theory calculations and kinetic studies suggest the reaction is catalyzed by trace copper salts and that a Z- to E-hydrazone isomerization occurs through an enehydrazine intermediate before the rate-determining cyclization of the hydrazone onto the alkyne group. The aminopyrrole products are obtained in 36-93% isolated
介绍了形成环氨基吡咯的新杂环异构化反应的机理研究。密度泛函理论计算和动力学研究表明,该反应是由痕量铜盐催化的,并且在腙到炔基上的限速环化之前,通过烯肼中间体发生 Z 到 E 腙异构化。取决于炔基取代基的性质,以36-93%的分离产率获得氨基吡咯产物。开发了一种新的自动采样技术以获得可靠的机械数据。
Chemoselectivity Control: Gold(I)-Catalyzed Synthesis of 6,7-Dihydrobenzofuran-4(5<i>H</i>)-ones and Benzofurans from 1-(Alkynyl)-7-oxabicyclo[4.1.0]heptan-2-ones
作者:Tao Wang、Shuai Shi、Mie Højer Vilhelmsen、Tuo Zhang、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1002/chem.201301698
日期:2013.9.9
chemoselective gold(I)‐catalyzed transformations of 1‐(arylethynyl)‐7‐oxabicyclo[4.1.0]‐ heptan‐2‐ones were developed. Two completely different products—6,7‐dihydrobenzofuran‐4(5H)‐ones and benzofurans—could be obtained from the same starting material. The selectivity is determined by the ligand of the gold catalyst: triphenylphosphine delivers 6,7‐dihydrobenzofuran‐4(5H)‐ones, and 1,3‐bis(diisopro