Copper Acetate–DMSO Promoted Methylthiolation of Arenes and Heteroarenes
作者:Poonam Sharma、Sandeep Rohilla、Nidhi Jain
DOI:10.1021/acs.joc.5b00443
日期:2015.4.17
An unprecedented copper acetate–DMSO promoted methylthiolation of arenes and heteroarenes in the presence of air has been developed. The reaction is highly regioselective under the directing group influence of pyridine and pyrimidine functional units and gives the thiomethylated product in moderate to high yields.
pyridinium salts from the reaction of various 2‐aryl‐pyridines and 2‐aryl‐sp2‐nitrogen‐atom‐containing heterocycles with alkynesthroughrhodium(III)‐catalyzed CH activation and annulation under an O2 atmosphere is described. A possible mechanism that involves the chelation‐assisted CH activation of the 2‐aryl‐pyridine substrate, insertion of the alkyne, and reductive elimination is proposed. This
Deprotonative Metalation of Aromatic Compounds by Using an Amino-Based Lithium Cuprate
作者:Tan Tai Nguyen、Nada Marquise、Floris Chevallier、Florence Mongin
DOI:10.1002/chem.201100990
日期:2011.9.5
employed to attempt the interception of the generated aryl cuprates, aroyl chlorides, iodomethane, and diphenyl disulfide efficiently reacted. In addition, different oxidative agents were identified to afford symmetrical biaryls. Finally, palladium‐catalyzed coupling with arylhalides was optimized and allowed the synthesis of different arylderivatives in medium to good yields.
A highly regioselective synthesis of pyrido[2,1‐a]isoindolium salts from 2‐arylpyridines and two equivalents of electron‐deficient alkenes catalyzed by rhodium is demonstrated. The reaction was carried out in aqueousmedium at 110 °C using inexpensive oxygen as oxidant. Reverse aza‐Michael addition of the isoindolium salt occurs when the salt was treated with base to give a β‐disubstituted alkene product
证明了由2-芳基吡啶和两当量的铑催化的电子等效的缺电子烯烃可高度区域选择性地合成吡啶并[ 2,1- a ]异吲哚盐。使用廉价的氧气作为氧化剂,在110℃的水性介质中进行反应。当用碱处理该盐以得到β-二取代的烯烃产物时,就会发生异吲哚鎓盐的反向氮杂-迈克尔加成反应。提出了一种反应机理,涉及烯烃与2-芳基吡啶的邻位C H烯化反应,分子内氮杂迈克尔基加成反应,烯烃片段β碳上的去质子化反应,然后另一种迈克尔加成反应生成最终产物。
Terashima, Masanao; Seki, Koh-ichi; Yoshida, Chihiro, Chemical and pharmaceutical bulletin, 1985, vol. 33, # 3, p. 1009 - 1015