化学选择性、区域选择性、非对映选择性和对映选择性的控制是有机合成的中心主题。获得分子的全套立体异构体的能力将显着提高合成天然产物类似物和创建用于药物发现的手性化合物库的效率。尽管过去几十年在不对称合成领域取得了巨大进步,但在催化剂控制的反应中精确控制相对和绝对构型,从而产生多个立体中心仍然是一个重大的合成挑战。我们在这里报告了具有迄今为止无法实现的选择性的催化剂控制的硼氢化反应的发展。Rh 催化的 α, β-不饱和羰基化合物与频哪醇硼烷的硼氢化反应以高水平的区域-、非对映-、和对映选择性提供具有两个邻位立体中心的硼氢化产物。Through the appropriate choice of substrate geometry ( E or Z) and ligand enantiomer ( S or R), all the possible diastereoisomers are readily
A simple and practical thio-Michael addition of α,β-unsaturatedamides catalyzed by Nmm-based ionic liquids with a 1,2-propanediol group has been developed. All the α,β-unsaturatedamides without substituents at the carbon end could smoothly react with sulfur-nucleophiles in water. Meanwhile for thio-Michael addition of α,β-unsaturatedamides with substituents at the carbon end, the relevant product
�ber einige ?-substituierte Fetts�ureamide mit lokalan�sthetischer Wirkung
作者:A. E. Wilder Smith、Emil Hofstetter
DOI:10.1002/hlca.19550380502
日期:——
The preparation and properties of further fatty acid anilides showing anaesthetic action are described and the relationship between chemical constitution and physiological effect is discussed. Two very active compounds having relatively low toxicities have been discovered, namely:-
α,β-Unsaturated acids, through their acid chlorides, react with tritylamine in the presence of triethylamine under mild conditions, to afford in high yield and high regioselectivity the corresponding β,γ-unsaturated tritylamides. Detritylation with TFA generates quantitatively β,γ-unsaturated primary amides. An investigation of this deconjugative isomerization was performed.
Palladium-catalyzed carbonylative synthesis of α,β-unsaturated amides from aryl azides and alkenylaluminum reagent
作者:Bo Chen、Xiao-Feng Wu
DOI:10.1016/j.jcat.2020.01.017
日期:2020.3
In this work, an interesting procedure for the synthesis of α,β-unsaturatedamides from aryl azides and alkenylaluminum reagent has been developed. With palladium as the catalyst and XPhos as the ligand under carbon monoxide pressure, the desired α,β-unsaturatedamides were isolated in good to excellent yields with good functional group tolerance. Remarkably, this procedure also represents an example