Visible-light synthesis of 4-substituted-chroman-2-ones and 2-substituted-chroman-4-ones <i>via</i> doubly decarboxylative Giese reaction
作者:Marek Moczulski、Ewelina Kowalska、Elżbieta Kuśmierek、Łukasz Albrecht、Anna Albrecht
DOI:10.1039/d1ra05914a
日期:——
Doubly decarboxylative, photoredox synthesis of 4-substituted-chroman-2-ones and 2-substituted-chroman-4-ones is described. The reaction involves two independent decarboxylation processes: the first one initiating the cycle and the second completing the process. Visible light, photoredox catalyst, base, anhydrous solvent and inert atmosphere constitute the key parameters for the success of the developed
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。
ENGBERSEN, J. F. J.;KOUDIJS, A.;VAN, DER, PLAS, H. C., J. HETEROCYCL. CHEM., 1982, 19, N 6, 1281-1283
作者:ENGBERSEN, J. F. J.、KOUDIJS, A.、VAN, DER, PLAS, H. C.
DOI:——
日期:——
Photo-Mediated Decarboxylative Giese-Type Reaction Using Organic Pyrimidopteridine Photoredox Catalysts
作者:Firas El-Hage、Christopher Schöll、Jola Pospech
DOI:10.1021/acs.joc.0c01955
日期:2020.11.6
The decarboxylativeGiese-typereaction offers a versatile methodology for the radical alkylation of electron-deficient alkenes. Photo-mediated variants often require a pre-activation of carboxylicacids and/or employment of costly transition-metal photocatalysts. Herein, we present a metal-free photocatalyzed decarboxylativeGiese-type addition to electron-deficient alkenes using pyrimidopteridine