本文描述了炔烃的无金属双官能化,以通过亚乙烯基邻甲基醌(VQM)的自发硒代磺酰基化来获得四取代的烯烃。反应在温和条件下进行,没有任何催化剂或添加剂。初步的机理研究表明,VQM的形成是这种炔烃双官能化反应的关键。该反应可用于轴向手性苯乙烯的对映选择性不对称合成。此外,硒代磺酰化加合物可以转化为有用的萘[2,1- b ]呋喃和苯并呋喃支架。
已开发出一种有效的,选择性的方法,可以从容易获得的二硒化物和苯乙酸合成含一个或两个双键C-Se键的硒醚。通过在无金属条件下将空气用作氧化剂来制备包含一个C-Se键的化合物,而通过氯化铁(III)/氧/碳酸铯(FeCl 3 / O 2)形成具有两个双键C-Se键的化合物。/ Cs 2 CO 3)系统。此外,在标准反应条件下,1,2-二苯基二硫烷也可以平稳地转化为相应的硫醚产物。
The first general methodology for the directthiolation of electron‐rich heteroarenes was developed by employing Pd/Al2O3, a recoverable and commercially available heterogeneous catalyst, and CuCl2. This method represents an operationally simple approach for the synthesis of these valuable compounds. Preliminary mechanistic studies indicate a heterogeneous catalytic system, in which both metals play
通过使用Pd / Al 2 O 3(一种可回收和可商购的非均相催化剂)和CuCl 2开发了第一种富电子杂芳烃直接硫醇化的通用方法。该方法代表了用于合成这些有价值的化合物的操作简单的方法。初步的机理研究表明,多相催化体系中的两种金属在硫醇化产物的形成中起着互补的作用。
Ruthenium Catalyzed C–H Selenylations of Aryl Acetic Amides and Esters via Weak Coordination
作者:Zhengyun Weng、Xinyue Fang、Meicui He、Linghui Gu、Jiafu Lin、Zheyu Li、Wenbo Ma
DOI:10.1021/acs.orglett.9b02196
日期:2019.8.16
An efficient ruthenium-catalyzed direct C–H selenylation of aryl acetic amides and esters has been achieved via distal weakly coordination. Notable features of this protocol including broad substrate scope, wide functional group tolerance, and good regioselectivity. In addition, diaryl disulfides were also successfully applied to this reaction under slightly modified conditions.
Organocatalytic selenosulfonylation of the C–C doublebond of α,β-unsaturatedketones to construct two contiguous stereogenic centers in an aqueous medium was described. A series of α-selenyl and β-sulfonyl ketones with various functional groups were synthesized in good yields and enantioselectivities with saturated NaCl solution as the solvent. In addition, this protocol had been successfully scaled
Copper-Catalyzed 8-Aminoquinoline-Directed Selenylation of Arene and Heteroarene C–H Bonds
作者:Anup Mandal、Harekrishna Sahoo、Mahiuddin Baidya
DOI:10.1021/acs.orglett.6b01420
日期:2016.7.1
An efficient copper-catalyzed/-mediated and 8-aminoquinoline-assisted arylselenylation of inert C–H bonds of (hetero)arenes with readily available diselenides has been reported. The reaction is scalable and tolerates a wide spectrum of functional groups to deliver diarylselenides in very high yields (up to 98%). Application of this methodology to the facile synthesis of thiophene-fused selenochromone
A copper-catalyzed regioselective C–H selenylation of quinolines with readily available diaryl diselenides is developed based on a chelation-controlled radical cross-coupling strategy. The reaction is scalable, tolerates a wide spectrum of functional groups, and proceeds with excellent C5 regioselectivity to deliver selenoquinolines in high yields (up to 98 %). A single electron transfer (SET) mediated