Quaternization at the picolinic carbon. Application to the synthesis of pyridylalkanecarboxylic acids
作者:Eric Pasquinet、Patrick Rocca、Alain Godard、Francis Marsais、Guy Quéguiner
DOI:10.1039/a805778h
日期:——
The paper describes two different methodologies for the construction of a quaternary center at the picolinic site, and their application to the synthesis of pyridylalkanecarboxylic acids. The first one involves a one-pot acetylation–Michael addition procedure followed by an alkylative quaternization of the picolinic carbon. The second one is based on the deprotonation at the picolinic carbon of 2-(α,α-dialkyl)pyridines using the superbasic mixture BuLi–diisopropylamine–ButOK (“KDA”). Both routes give very good yields.
该论文描述了在吡啶酸位点构建四元中心的两种不同方法及其在合成吡啶基烷基羧酸中的应用。第一种方法涉及一次性醋酸化-迈克尔加成程序,随后进行吡啶碳的烷基化铵化。第二种方法基于对2-(α,α-二烷基)吡啶的吡啶碳进行去质子化,使用超级碱性混合物BuLi–二异丙胺–ButOK(“KDA”)。两条路线均能获得非常好的产率。