Remarkably Facile Hexatriene Electrocyclizations as a Route to Functionalized Cyclohexenones via Ring Expansion of Cyclobutenones
摘要:
This Communication describes a cascade reaction sequence that leads to highly functionalized cyclohexenones starting from reaction of cyclobutenones with alpha-lithio-alpha,beta-unsaturated sulfones and amides. The hexatriene-cyclohexadiene cyclization steps presumed to be involved in these transformations are among the most facile hexatriene electrocyclizations reported thus far.
Electrosynthesis of (<i>E</i>)-Vinyl Sulfones Directly from Cinnamic Acids and Sodium Sulfinates via Decarboxylative Sulfono Functionalization
作者:Peng Qian、Meixiang Bi、Jihu Su、Zhenggen Zha、Zhiyong Wang
DOI:10.1021/acs.joc.6b00661
日期:2016.6.3
A variety of (E)-vinyl sulfones were constructed directly from cinnamic acids and sodium sulfinates with high regioselectivity at room temperature by virtue of an electrocatalytic oxidation. A radical intermediate was detected, and the corresponding mechanism was investigated.
A transition-metal-free synthesis of vinyl sulfones, utilizing sodium sulfinates and cinnamic acids through tandem cross-decarboxylative/coupling reactions, has been developed.
一种不含过渡金属的乙烯磺酰合成方法已经开发出来,它利用了亚硫酸钠和肉桂酸通过串联的脱羧/偶联反应。
<i>E</i>-Selective synthesis of vinyl sulfones <i>via</i> silver-catalyzed sulfonylation of styrenes
作者:Qingwen Gui、Kang Han、Zhuoliang Liu、Zhaohong Su、Xiaoli He、Hongmei Jiang、Bufan Tian、Yangyan Li
DOI:10.1039/c8ob01502c
日期:——
An efficient and highly E-selective protocol for the synthesis of vinyl sulfones is described. This simple protocol demonstrates the first synthesis of vinyl sulfonesvia a silver-catalyzed C–S bond coupling reaction. In addition, the success of the reaction was found to be critically dependent on the use of TEMPO as the additive.
Intermolecular [2 + 2] Photocycloaddition of α,β-Unsaturated Sulfones: Catalyst-Free Reaction and Catalytic Variants
作者:Noah Jeremias、Lisa-Marie Mohr、Thorsten Bach
DOI:10.1021/acs.orglett.1c01794
日期:2021.8.6
2-Aryl-1-sulfonyl-substituted cyclobutanes were prepared in an intermolecular [2 + 2] photocycloaddition from various α,β-unsaturated sulfones and olefins upon irradiation at λ = 300 nm (26 examples, 60–99% yield). Lewisacids catalyzed the [2 + 2] photocycloaddition of 2-benzimidazolyl styryl sulfones. At short wavelengths, the latter substrates underwent C–S bond cleavage but AlBr3 (5 mol %) allowed
Visible‐Light‐Induced Three‐Component Intermolecular Trifluoromethyl‐Alkenylation Reactions of Unactivated Alkenes
作者:Yuan‐Qiang Guo、Kaihua Wang、Ruiguo Wang、Hongjian Song、Yuxiu Liu、Qingmin Wang
DOI:10.1002/adsc.202001434
日期:2021.3.16
visible‐light‐induced three‐component intermolecular trifluoromethyl‐alkenylation reactions of unactivated alkenes. The protocol has good functional group tolerance and a broad substrate scope. Using this protocol, we not only introduced a trifluoromethyl group into alkenes but also converted unactivated alkenes to styrene‐based activated alkenes, in addition to accomplishing late‐stage functionalization of pharmaceutical