Reactivity of [bis(1-adamantylcarbonyloxy)iodo]arenes in substitution and addition reactions
摘要:
The reactivity of [bis(1-adamantylcarbonyloxy)iodo] arenes with 4-methylquinoline (substitution) as a typical heteroaromatic base and phenyl vinyl sulfone (addition) as atypical activated olefin has been studied under thermal and irradiation conditions. The results suggest that electron-withdrawing groups on the aromatic ring in [bis(1-adamantylcarbonyloxy)iodo]arenes are detrimental to reactions. The crystal structures of [bis(1-adamantylcarbonyloxy)iodo]arenes Ib and le are reported.
Catalyst‐Free Decarboxylation of Carboxylic Acids and Deoxygenation of Alcohols by Electro‐Induced Radical Formation
作者:Xiaoping Chen、Xiaosheng Luo、Xiao Peng、Jiaojiao Guo、Jiantao Zai、Ping Wang
DOI:10.1002/chem.201905224
日期:2020.3.12
derived from naturally abundant carboxylic acids and alcohols provides a sustainable and inexpensive approach to radical formation via undivided electrochemical cells. The resulting radicals are trapped by an electron-poor olefin or hydrogen atom source to furnish the Giese reaction or reductive decarboxylation products, respectively. A broad range of carboxylic acid (1°, 2°, and 3°) and alcohol (2° and
Photoredox-Catalyzed Deaminative Alkylation via C–N Bond Activation of Primary Amines
作者:Melissa A. Ashley、Tomislav Rovis
DOI:10.1021/jacs.0c08595
日期:2020.10.28
starting materials. For these reasons, deaminative functionalization of amines has emerged as an important area of research. Recent advances in C-N activation transform simple α-1° and α-2° amines into alkylating reagents via Katritzky pyridinium salts. We report a complementary method that activates sterically encumbered α-3° primary amines through visiblelight photoredox catalysis. By condensing α-3°
Decarboxylative Giese-Type Reaction of Carboxylic Acids Promoted by Visible Light: A Sustainable and Photoredox-Neutral Protocol
作者:Nieves P. Ramirez、Jose C. Gonzalez-Gomez
DOI:10.1002/ejoc.201601478
日期:2017.4.18
for decarboxylative generation of radicals from carboxylicacids and their 1,4-addition to Michael acceptors. The Fukuzumi catalyst ([Acr+-Mes]) enabled this transformation under visiblelight irradiation, at room temperature and with CO2 as the only byproduct. Scope and limitations of this protocol were examined using a range of Michael acceptors (15 examples) and a diverse array of carboxylic acids
这项工作描述了一种无过渡金属的方法,用于从羧酸中脱羧生成自由基及其与迈克尔受体的 1,4-加成。Fukuzumi 催化剂 ([Acr+-Mes]) 在可见光照射下、在室温下和 CO2 作为唯一副产物的情况下实现了这种转变。使用一系列迈克尔受体(15 个示例)和各种羧酸(18 个示例)检查了该协议的范围和限制。在该协议中使用 3-羟基新戊酸允许直接形成非对映异构纯 δ-内酯。此外,当使用高烯丙酸时,会发生自由基级联反应,形成三个 CC 键。
Electrochemical radical reactions of alkyl iodides: a highly efficient, clean, green alternative to tin reagents
作者:Diyuan Li、Tsz-Kan Ma、Reuben J. Scott、Jonathan D. Wilden
DOI:10.1039/d0sc01694b
日期:——
C-centered radicals. Intermolecular ‘tin-like’ radical reactions can subsequently be conducted under the most benign of conditions. The yields and efficiency of the processes are competitive and even superior in most cases to comparable conditions with tributyltin hydride. The use of air and electricity as the promotor (instead of a tin or other reagent) combined with the aqueous reaction media make this
Catalyst-Controlled C–H Functionalization of Adamantanes Using Selective H-Atom Transfer
作者:Hai-Bin Yang、Abigail Feceu、David B. C. Martin
DOI:10.1021/acscatal.9b01394
日期:2019.6.7
been developed using photoredox and H atom transfer catalysis. This C–H alkylation reaction has excellent chemoselectivity for the strong 3° C–H bonds of adamantanes in polyfunctional molecules. In substrate competition reactions, a reversal in selectivity is observed for the new H-atom transfer catalyst reported here in comparison to five known photochemical systems. Derivatization of a broad scope