functionality has been reliably transferred into nucleophilic radicals with the loss of one molecule of formaldehyde. Intriguingly, we found that the dehydroxymethylation process can be significantly promoted by the cerium catalyst, and the stabilization effect of the fragmented radicals also plays a significant role. This operationally simple protocol has enabled the direct utilization of primary alcohols as unconventional
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。
Alkyl‐GeMe
<sub>3</sub>
: Neutral Metalloid Radical Precursors upon Visible‐Light Photocatalysis
作者:Qing‐Hao Xu、Li‐Pu Wei、Bin Xiao
DOI:10.1002/anie.202115592
日期:2022.3.28
Alkyl-GeMe3 was proven to be an effective radicalprecursor under visible-light photocatalysis. The metalloid nature of Ge allows single-electron transfer (SET) at the neutral Ge center and leads to advantages in separation and derivatization.
在可见光光催化下,烷基-GeMe 3被证明是一种有效的自由基前体。Ge 的准金属性质允许在中性 Ge 中心进行单电子转移 (SET),并在分离和衍生化方面具有优势。
Decarboxylative C-C and C-N Bond Formation by Ligand-Accelerated Iron Photocatalysis
作者:Guangshou Feng、Xiaofei Wang、Jian Jin
DOI:10.1002/ejoc.201901381
日期:2019.10.24
A mild, practical protocol for the decarboxylative C–C and C–N bondformation has been accomplished. The method proceeds through an intramolecular charge transfer pathway of iron–substrate complexes under visible light irradiation.
Alkyl Radical Generation via C–C Bond Cleavage in 2-Substituted Oxazolidines
作者:Adrián Luguera Ruiz、Marta La Mantia、Daniele Merli、Stefano Protti、Maurizio Fagnoni
DOI:10.1021/acscatal.2c03768
日期:2022.10.7
corresponding aldehydes) have been herein employed for the successful release of tertiary, α-oxy, and α-amido radicals under photo-organo redox catalysis. The reaction relies on the unprecedented C–Ccleavage occurring from the radical cation of these heterocyclic derivatives. Such a protocol is applied to the visible-light-driven conjugate radical addition onto Michael acceptors and vinyl (hetero)arenes
迫切需要开发在温和的光催化条件下被激活的不带电自由基前体。2-取代-1,3-恶唑烷(E ox < 1.3 V vs SCE,由相应的醛顺利制备)已被用于在光有机氧化还原下成功释放叔、α-氧基和 α-酰胺自由基催化。该反应依赖于这些杂环衍生物的自由基阳离子发生的前所未有的 C-C 裂解。这种协议适用于在温和的无金属条件下将可见光驱动的共轭自由基加成到迈克尔受体和乙烯基(杂)芳烃上。