Functionalization of pyridine via direct metallation
作者:Jacob Verbeek、Albert V. E. George、Robertus L. P. de Jong、Lambert Brandsma
DOI:10.1039/c39840000257
日期:——
The isolation of mixtures of 2-, 3-, and 4-deuteriopyridine, 2-, 3-, and 4-trimethylsilylpyridine, or 2-, 3-, and 4-methylthiopyridine indicates successful metallation of pyridine with a 1 : 1 mixture of BuLi-ButOK in tetrahydrofuran–hexane at ––100 °C.
2-,3-和4-氘代吡啶,2-,3-和4-三甲基甲硅烷基吡啶或2-,3-和4-甲硫基吡啶的混合物的分离表明,吡啶与1:1的混合物成功地金属化在––100°C下于四氢呋喃–己烷中的BuLi-Bu t OK。
Generation and Reactions of Pyridyllithiums via Br/Li Exchange Reactions Using Continuous Flow Microreactor Systems
作者:Aiichiro Nagaki、Daisuke Yamada、Shigeyuki Yamada、Masatomo Doi、Daisuke Ichinari、Yutaka Tomida、Naofumi Takabayashi、Jun-ichi Yoshida
DOI:10.1071/ch12440
日期:——
A continuous flowmicroreactor method for generating and carrying out reactions on pyridyllithiums has been developed based on Br/Li exchange reactions of bromopyridines and dibromopyridines. The reactions can be carried out without using cryogenic conditions by virtue of short residence times and efficient heat transfer, while very low temperatures such as –78 or –110°C are required for conventional
[EN] 2-SUBSTITUTED ISOFLAVONOID COMPOUNDS, MEDICAMENTS AND USES<br/>[FR] COMPOSÉS ISOFLAVONOÏDES SUBSTITUÉS EN POSITION 2, MÉDICAMENTS ET UTILISATIONS
申请人:NOVOGEN RES PTY LTD
公开号:WO2009003229A1
公开(公告)日:2009-01-08
2-Substituted isoflavonoid compounds and pharmaceutical compositions containing same are useful as anti-inflammatory agents and antioxidants and for the treatment of related diseases and conditions.
CO<sub>2</sub>
Conversion into Esters by Fluoride-Mediated Carboxylation of Organosilanes and Halide Derivatives
作者:Xavier Frogneux、Niklas von Wolff、Pierre Thuéry、Guillaume Lefèvre、Thibault Cantat
DOI:10.1002/chem.201505092
日期:2016.2.24
A one‐step conversion of CO2 into heteroaromatic esters is presented under metal‐free conditions. Using fluoride anions as promoters for the C−Si bond activation, pyridyl, furanyl, and thienyl organosilanes are successfully carboxylated with CO2 in the presence of an electrophile. The mechanism of this unprecedented reaction has been elucidated based on experimental and computational results, which
Unusual<i>t</i>-BuLi Induced Ortholithiation versus Halogen-Lithium Exchange in Bromopyridines: Two Alternative Strategies for Functionalization
作者:Philippe Gros、Yves Fort、Philippe Pierrat
DOI:10.1055/s-2004-831337
日期:——
The reaction of lithiating agents with various 3-bromopyridines has been investigated. An unprecedented selectivity was observed with t-BuLi, which effected a clean lithiation at C-4. With 3-bromo and 2-chloro-3-bromo pyridines, the ortholithiation-exchange ratio was strongly electrophile and addition order dependent while 2-chloro-5-bromopyridine always gave exclusive C-4 substitution.