Efficient AgOTf or Ph3PAuCl–AgSbF6 catalyzed cyclization of 1-hydroxy-2-alkynylallylphosphonates/2-alkynylallyl alcohols to 2-furylphosphonates/2,3,5-trisubstituted furans
摘要:
The reaction of 1-hydroxy-2-alkynylallylphosphonates, synthesized by the addition of the corresponding phosphites to 2-alkynylcinnamaldehydes, under AgOTf or Ph3PAuCl-AgSbF6 catalyzed cycloisomerization afforded 2-furylphosphonates in good to excellent yields. These cyclization reactions were compared with those of 2-alkynylallyl alcohols that led to multisubstituted furans. (C) 2012 Published by Elsevier Ltd.
Synthesis of 2-Tetrazolyl-Substituted 3-Acylpyrroles via a Sequential Ugi-Azide/Ag-Catalyzed Oxidative Cycloisomerization Reaction
作者:Han-Han Kong、Hong-Ling Pan、Ming-Wu Ding
DOI:10.1021/acs.joc.8b01984
日期:2018.10.19
cascade cycloisomerization/aerobic oxidation reaction of a Ugi-azide adduct for the preparation of 3-acylpyrroles using molecular oxygen as the terminal oxidant has been developed. A series of 2-tetrazolyl-substituted 3-acylpyrroles were obtained in 62–89% yields from readily available enynals 1, primaryamines2, isocyanides 3, and trimethylsilyl azide 4 in the presence of a catalytic amount of AgNO3 and
Gold-Catalyzed Cascade Reactions of Furan-ynes with External Nucleophiles Consisting of a 1,2-Rearrangement: Straightforward Synthesis of Multi-Substituted Benzo[<i>b</i>]furans
作者:Ning Sun、Xin Xie、Yuanhong Liu
DOI:10.1002/chem.201400112
日期:2014.6.10
A gold‐catalyzed cycloisomerization of silyl‐protected 2‐(1‐alkynyl)‐2‐alken‐1‐(2‐furanyl)‐1‐ols with various nucleophiles including water, alcohol, aniline, sulfonamide, and electron‐rich arene has been developed. The method provides a highly efficient access to 5,7‐disubstituted or 2,5,7‐trisubstituted benzo[b]furans with a wide diversity of substituents under mild reaction conditions, which are
甲硅烷基保护的2-(1-炔基)-2-烯基-1-(2-呋喃基)-1-醇与各种亲核试剂(包括水,醇,苯胺,磺酰胺和富电子芳烃)的金催化环异构化反应已开发。该方法提供了以高效率的存取5,7-二取代的或2,5,7-三取代的苯并[ b ]呋喃与取代基的反应条件温和,这是不通过其他方法容易获得下一个广泛的多样性。值得注意的是,在环化过程中,烷基从呋喃环的C2到C3位置发生了有趣的重排。通过以下金辅助的烯丙基取代,可以在其C5位侧链上修饰具有广泛官能团的苯并[ b ]呋喃。
One-Pot Synthesis of Indole-Fused Scaffolds via Gold-Catalyzed Tandem Annulation Reactions of 1,2-Bis(alkynyl)-2-en-1-ones with Indoles
作者:Xin Xie、Xiangwei Du、Yifeng Chen、Yuanhong Liu
DOI:10.1021/jo2017668
日期:2011.11.4
The gold-catalyzed tandem cyclization of 1,2-bis(alkynyl)-2-en-1-ones with indoles offers an efficient and straightforward route to indole-fused polycyclic systems. The process is realized through a cascade carbonyl-yne cyclization/Friedel–Crafts/indole-yne cyclization sequence catalyzed by a single-pot catalyst of gold.