在相转移催化(PTC)下,由邻-(1-炔基苯氧基)-1-苯基乙酮在温和的反应条件下,可以容易地以良好的产率或优异的产率制备各种取代的苯并[ b ]呋喃。该方法学适用于简单的实验操作,廉价且对环境无害的催化剂,无金属催化剂的条件,简便的试剂以及进行大规模制备的可能性。通过整体结构异构化发展碳-碳键形成过程代表了最经济的方法。
Rh(III)-Catalyzed and Solvent-Controlled Chemoselective Synthesis of Chalcone and Benzofuran Frameworks via Synergistic Dual Directing Groups Enabled Regioselective C–H Functionalization: A Combined Experimental and Computational Study
between the hydroxyl group and the Rh(III) catalyst play a decisive role in promoting the regioselective migratory insertion of the alkyne moiety. Thereafter, two solvent-controlled switchable reaction pathways, which respectively involvetandem β–H elimination/hydrogen transfer/oxidative addition/C–O bond reductive elimination/oxidation (for low-polar solvents: path I–Ia via a RhIII–RhI–RhIII pathway)
借助协同双指导基团(O–NHAc部分和羟基)辅助策略,有效和实用的Rh(III)催化的区域选择性氧化还原中性C–H功能化了多种N已经实现了具有炔丙醇的β-苯氧基乙酰胺,其导致以溶剂控制的化学选择性方式多样化地合成了优先的苯并呋喃和查尔酮骨架。实验和计算研究表明,双指导基团之间氢键的形成以及随后的羟基与Rh(III)催化剂之间的配位相互作用在促进炔烃部分的区域选择性迁移插入中起决定性作用。此后,二溶剂控制的切换的反应途径,其分别涉及串联β-H消除/氢转移/氧化加成/ C-O键还原消除/氧化(低极性溶剂:路径我-我一个经由铑III -铑我-Rh III途径)和氧化加成/β-H消除/氢转移/质子分解(用于高极性溶剂:路径II - II b经由铑III -Rh V -Rh III途径),后跟提供相应的化学选择性优异的产品。综上所述,我们在此给出的结果不仅扩展了O-NHAc定向的C-H活化的范围,而
benzo[b]furans and 3-methyl-2-substituted benzo[b]thiophenes using low-cost, abundant, and easy-to-use solid calcium carbide instead of flammable and explosive gaseous acetylene as an original alkyne source, o-bromophenyl ethers or o-bromophenyl thioethers as substrates through an intramolecular carbanion-yne cyclization in a 5-exo-dig manner, and subsequent double-bond isomerization is described.
一种使用低成本、丰富且易于使用的固体碳化钙来简便构建 3-甲基-2-取代苯并[ b ]呋喃和 3-甲基-2-取代苯并[ b ]噻吩的简明方法描述了以易燃易爆的气态乙炔为原始炔烃源,以邻溴苯醚或邻溴苯硫醚为底物,通过5- exo-dig方式进行分子内碳负离子-炔环化,以及随后的双键异构化。两个C-C键的同时形成是通过一步路线实现的。该方法的优点还包括底物范围广、产率高和后处理操作简单。该合成策略也适用于克级。
Bi(OTf)
<sub>3</sub>
‐Mediated (4+1) Annulation of α‐Sulfonyl
<i>o</i>
‐Hydroxyacetophenones with α‐Hydroxy Arylketones to Access Sulfonyl 2‐Aroylbenzofurans
作者:Meng‐Yang Chang、Kuan‐Ting Chen
DOI:10.1002/adsc.202100143
日期:2021.5.18
AbstractIn this paper, a high‐yield, facile route for the scalable synthesis of sulfonyl 2‐aroylbenzofurans via a Bi(OTf)3‐mediated intermolecular double cyclocondensation of α‐sulfonyl o‐hydroxyacetophenones with substituted α‐hydroxy arylketones under mild open‐vessel reaction conditions is described. In the overall reaction, water is generated as the only byproduct. Various metal triflate‐promoted reactions and conditions are investigated for the efficient one‐pot (4+1) annulation reaction.magnified image
Phase-Transfer-Catalyzed Intramolecular Cyclization of<i>ortho</i>-Alkynyl Phenyl Ether Derivatives for Synthesis of 2,3-Disubstituted Benzo[<i>b</i>]furans
A variety of substituted benzo[b]furans are readily prepared in good to excellent yields under the mild reaction conditions from o-(1-alkynylphenoxy)-1-phenylethanone under phase-transfer catalysis (PTC). This methodology accommodates simple experimental operations, inexpensive and environmentally benign catalysts, metal catalyst-free conditions, facile reagents and the possibility to conduct large-scale
在相转移催化(PTC)下,由邻-(1-炔基苯氧基)-1-苯基乙酮在温和的反应条件下,可以容易地以良好的产率或优异的产率制备各种取代的苯并[ b ]呋喃。该方法学适用于简单的实验操作,廉价且对环境无害的催化剂,无金属催化剂的条件,简便的试剂以及进行大规模制备的可能性。通过整体结构异构化发展碳-碳键形成过程代表了最经济的方法。
Synthesis and antifungal activities of some aryl [3-(imidazol-1-yl/triazol-1-ylmethyl) benzofuran-2-yl] ketoximes
In this study, somearyl [3-(imidazol-1-yl/triazol-1-ylmethyl)benzofuran-2-yl] ketones, aryl (3-methyl-benzofuran-2-yl) ketoximes and aryl [3-(imidazol-1-yl/triazol-1-ylmethyl)benzofuran-2-yl] ketoximes were synthesised starting from 2-aryloyl-3-methyl-benzofuranes. The structure elucidation of the compounds was performed by IR, 1H-NMR, MASS spectroscopy and elemental analyses. Antifungal activities