Phosphomolybdic acid as a bifunctional catalyst for Friedel-Crafts type dehydrative coupling reaction
作者:Guo-Ping Yang、Dilireba Dilixiati、Tao Yang、Dong Liu、Bing Yu、Chang-Wen Hu
DOI:10.1002/aoc.4450
日期:2018.9
Phosphomolybdic acid (H3PMo12O40) was found to be a bifunctional catalyst for C─C bond formation via the dehydrative reaction of diarylmethanols with various nucleophiles, including 2‐naphthols, indoles, benzofuran and benzothiophene. The protons in the catalyst might play a critical role in the activation of alcohol, while the polyanion was advantageous for stabilizing the carbocation species. The
磷钼酸(H 3 PMo 12 O 40)是通过二芳基甲醇与各种亲核试剂,包括2-萘酚,吲哚,苯并呋喃和苯并噻吩的脱水反应,形成C-C键的双功能催化剂。催化剂中的质子可能在醇的活化中起关键作用,而聚阴离子有利于稳定碳正离子。协同催化体系显示出其自身的优点,例如高反应速率,低催化剂负载,温和的条件,极好的收率(高达99%)和良好的官能团相容性。
Direct alkylation of aromatics using alcohols in the presence of NaHSO4/SiO2
Simple and efficient procedure for alkylation of aromatics from alcohols in the presence of NaHSO4/SiO2 was developed. Various triaryl methanes were obtained in good yields in short reaction time. For instance the reaction of mesitylene with benzhydrol in the presence of NaHSO4/SiO2 gave the corresponding triaryl methane in a quantitative yield. NaHSO4/SiO2 was regenerated by simple treatment and could
Organocatalyzed Friedel–Crafts arylation of benzylic alcohols
作者:J. Adam McCubbin、Oleg V. Krokhin
DOI:10.1016/j.tetlet.2010.02.151
日期:2010.5
Electron-rich aromatic and heteroaromatic rings are functionalized directly with a variety of benzylic alcohols under mild conditions. The reaction is catalyzed by commercially available pentafluorophenylboronic acid, which is stable under ambient conditions and recoverable. The reaction itself is highly atom economical and produces water as the only byproduct. A Friedel-Crafts mechanism is proposed. (C) 2010 Elsevier Ltd. All rights reserved.
Friedel-Crafts Alkylation with Carbenium Ions Generated by Electrochemical Oxidation of Stannylmethyl Ethers
作者:Anna Lielpetere、Aigars Jirgensons
DOI:10.1002/ejoc.202000568
日期:2020.8.9
Friedel–Crafts alkylation of electron rich arenes can be achieved by stabilized carbenium ions which are generated by single cell anodic oxidation of stannylmethyl ethers at low potential. The use of NaHCO3 as an additive ensures close‐to‐neutral conditions enabling the reaction with arenes bearing acid‐sensitive groups such as O‐TBS, O‐Tr, O‐MOM, O‐THP.