in palladium-catalyzed non-directed CH functionalization, leading to highly para-selective CH olefination of TIPS-protected phenols. This transformation displayed good generality in realizing various other para-selective CH functionalization reactions such as halogenation, and allylation reactions. A wide variety of phenol derivatives including bioactive molecules of triclosan, thymol, and propofol
钯催化的非定向CH功能化为芳烃的直接功能化提供了一种有效的方法,但它通常具有较差的位点选择性,限制了其广泛应用。在此,首次报道了3,5-二甲基金刚烷-1-羧酸(1-DMAdCO 2 H)的羧酸配体可以影响钯催化非定向反应中CH活化步骤中的位点选择性C H 官能化,导致 TIPS 保护的酚的高度对位选择性 C H 烯化。这种转化在实现其他各种对位选择性 C时显示出良好的通用性H 官能化反应,例如卤化和烯丙基化反应。多种苯酚衍生物,包括三氯生、百里酚和异丙酚的生物活性分子,都是相容的底物,从而以中等到良好的收率产生相应的对位选择性产物。一项初步的机制研究表明,羧酸配体和庞大的保护基之间的空间排斥因子导致了空间位阻较小的对位的选择性 C H 活化。这种新模型非定向对位选择性 C H 功能化可为远程位点选择性 C H 激活提供直接途径。
Converting Core Compounds into Building Blocks: The Concept of Regiochemically Exhaustive Functionalization
3-fluoropyridine were converted into all possible regioisomers of the corresponding carboxylic acids by passing through the corresponding organometallic intermediates. As an attempt to generalize the findings reveals, a restricted set of principles and methods suffices to cope with all std. scenarios. The most valuable and versatile tools for the regiochem. exhaustivefunctionalization of a great variety
Ni-Catalyzed Borylation of Aryl Fluorides via C–F Cleavage
作者:Xiang-Wei Liu、Javier Echavarren、Cayetana Zarate、Ruben Martin
DOI:10.1021/jacs.5b08103
日期:2015.10.7
A Ni-catalyzed borylation via C-Factivation is described. This protocol is distinguished by a wide scope, including unactivated fluoroarenes, without compromising its efficiency and scalability, thus representing a significant step-forward toward the implementation of C-Factivation protocols.