Blue LED Irradiation of Iodonium Ylides Gives Diradical Intermediates for Efficient Metal‐free Cyclopropanation with Alkenes
作者:Tristan Chidley、Islam Jameel、Shafa Rizwan、Philippe A. Peixoto、Laurent Pouységu、Stéphane Quideau、W. Scott Hopkins、Graham K. Murphy
DOI:10.1002/anie.201908994
日期:2019.11.18
A facile and highly chemoselective synthesis of doubly activated cyclopropanes is reported where mixtures of alkenes and β-dicarbonyl-derived iodoniumylides are irradiated with light from blue LEDs. This metal-free synthesis gives cyclopropanes in yields up to 96 %, is operative with cyclic and acyclic ylides, and proceeds with a variety of electronically-diverse alkenes. Computational analysis explains
Cyclohexenynone Precursors: Preparation via Oxidative Dearomatization Strategy and Reactivity
作者:Dachuan Qiu、Jiarong Shi、Qianyu Guo、Qiuxia Xu、Baosheng Li、Yang Li
DOI:10.1021/jacs.8b08915
日期:2018.10.17
A unique approach toward the preparation of cyclohexenynone equivalents was successfully developed viaoxidative dearomatization of aryne precursors, featuring multiple functionalities on the target rings. Upon activation, these in situ formed cyclohexenynone intermediates exhibit good to excellent reactivity with various trapping agents. Moreover, an unprecedented cascade was discovered with aryl
Metal-free intermolecular cyclopropanation between alkenes and iodonium ylides mediated by PhI(OAc)<sub>2</sub>·Bu<sub>4</sub>NI
作者:Jason Tao、Carl D. Estrada、Graham K. Murphy
DOI:10.1039/c7cc04859a
日期:——
A rapid, mild and metal-freeintermolecular cyclopropanation between iodonium ylides and alkene-containing substrates mediated by PhI(OAc)2·Bu4NI is reported. Iodonium ylides of cyclic and acyclic 1,3-dicarbonyls were reacted with a variety of mono-, di-, tri- and tetra-substituted alkenes of various structural types to give 29 cyclopropanes in up to 97% yield.
Expanding the Strained Alkyne Toolbox: Generation and Utility of Oxygen-Containing Strained Alkynes
作者:Tejas K. Shah、Jose M. Medina、Neil K. Garg
DOI:10.1021/jacs.6b01986
日期:2016.4.13
strained intermediates, the 4,5-benzofuranyne and the 3,4-oxacyclohexyne. In situtrapping of these intermediates affords an array of heterocyclic scaffolds by the formation of one or more new C-C or C-heteroatom bonds. Experimentally determined regioselectivities were consistent with predictions made using the distortion/interaction model and were also found to be greater compared to selectivities seen
我们报告了允许访问两个氧杂环应变中间体,4,5-苯并呋喃和 3,4-氧杂环己炔的合成方法。这些中间体的原位捕获通过形成一个或多个新的 CC 或 C-杂原子键提供了一系列杂环支架。实验确定的区域选择性与使用失真/相互作用模型所做的预测一致,并且还发现与在相应含氮中间体的捕获实验中看到的选择性相比更大。这些研究证明了氧杂环芳烃和炔烃在合成功能化杂环方面的多功能性,同时进一步扩大了变形/相互作用模型的范围。而且,
All‐Carbon Tetrasubstituted Olefins Synthesis from Diazo Compounds and Iodonium Ylides under Blue LED Irradiation
作者:Yan‐Rui Zhao、Lei Li、Guo‐Yong Xu、Jun Xuan
DOI:10.1002/adsc.202101144
日期:2022.2
tetra-substituted olefins through visible-light promoted coupling of diazo compounds with iodonium ylides was developed. A wide range of all-carbon tetra-substituted olefins was obtained in moderate to good yields. The synthetic values of the current method were further approved by the synthesis of natural isolates modified alkenes and the successful transformation of final olefins into important heterocycles