Pd-Catalyzed Tandem Chemoselective Synthesis of 2-Arylbenzofurans using Threefold Arylating Triarylbismuth Reagents
作者:Maddali L. N. Rao、Deepak N. Jadhav、Priyabrata Dasgupta
DOI:10.1002/ejoc.201201314
日期:2013.2
A tandemchemoselectivesynthesis of 2-arylbenzofurans was accomplished from o-hydroxy-gem-(dibromovinyl)benzenes and BiAr3 reagents under palladium-catalyzed conditions. This unique and synthetically valuable strategy proceeds through three consecutive coupling reactions involving triarylbismuthreagents and provides 2-arylbenzofuran products in high yields.
One-Pot Synthesis of Substituted Benzo[<i>b</i>]furans from Mono- and Dichlorophenols Using Palladium Catalysts Bearing Dihydroxyterphenylphosphine
作者:Miyuki Yamaguchi、Haruka Katsumata、Kei Manabe
DOI:10.1021/jo401503t
日期:2013.9.20
on the phosphorus atom (Cy-DHTP) was found to be a powerful ligand for the palladium-catalyzed one-potsynthesis of substituted benzo[b]furans from 2-chlorophenols and terminal alkynes. This catalyst system was also applicable to the sequential one-potsynthesis of disubstituted benzo[b]furans from dichlorophenols via the Suzuki–Miyaura cross-coupling of chlorobenzo[b]furan with boronic acids. The use
发现在磷原子上带有环己基的二羟基叔苯基膦(Cy-DHTP)是钯催化由一锅法从2-氯酚和末端炔烃合成取代苯并[ b ]呋喃的强配体。该催化剂体系还适用于通过氯苯并[ b ]呋喃与硼酸的Suzuki-Miyaura交叉偶联从二氯苯酚一步法一锅合成二取代的苯并[ b ]呋喃。Cy-DHTP和XPhos这两种配体的使用是促进反应的关键。机理研究表明,Pd–Cy-DHTP催化剂是Sonogashira交叉偶联步骤中的活性物种,而Pd–XPhos催化剂则加速了Suzuki–Miyaura交叉偶联步骤。
Transition-metal-free base catalyzed intramolecular cyclization of 2-ynylphenols for efficient and facile synthesis of 2-substituted benzo[<i>b</i>]furans
作者:Yong Liu、Tao Lu、Wei-Fang Tang、Jian Gao
DOI:10.1039/c8ra03882a
日期:——
A transition-metal-free basecatalyzedintramolecular cyclization of 2-ynylphenols was developed for the facile synthesis of 2-substituted benzo[b]furans. Various 2-aryl and 2-alkyl substituted benzo[b]furans can be obtained with good to excellent yields using readily available Cs2CO3 as the catalyst under mild reaction conditions. The broad substrates scope and the typical maintenance of vigorous
开发了一种无过渡金属碱催化的 2-炔基酚分子内环化,用于简便合成 2-取代的苯并[ b ]呋喃。使用容易获得的 Cs 2 CO 3作为催化剂,在温和的反应条件下,可以以良好至优异的收率获得各种 2-芳基和 2-烷基取代的苯并[ b ]呋喃。广泛的底物范围和克级高效效率的典型维持使该协议成为合成 2-取代苯并[ b ]呋喃衍生物的潜在实用方法。