Visible-light mediated sulfonylation of thiols <i>via</i> insertion of sulfur dioxide
作者:Akshay M. Nair、Shreemoyee Kumar、Indranil Halder、Chandra M. R. Volla
DOI:10.1039/c9ob01040h
日期:——
mediated synthesis of thiosulfonates via a radical–radical coupling of sulfenyl radicals and arylsulfonyl radicals was developed. The reaction of thiols, aryldiazonium tetrafluoroborates and DABSO proceeded at room temperature using 5 mol% eosin Y. The reaction displayed wide functional group tolerance and delivered the unsymmetrical thiosulfonates in good to excellent yields.
Organophotoredox-Catalyzed Formation of Alkyl–Aryl and −Alkyl C–S/Se Bonds from Coupling of Redox-Active Esters with Thio/Selenosulfonates
作者:Yue Dong、Peng Ji、Yueteng Zhang、Changqing Wang、Xiang Meng、Wei Wang
DOI:10.1021/acs.orglett.0c03624
日期:2020.12.18
A mild organophotoredox synthetic protocol for forming a Csp3–S/Se bond by reacting widespread redox-active esters with thio/selenosulfonates has been developed. The power of the synthetic manifold is fueled by an unprecedented broad substrate scope and wide functional group tolerance.
已经开发出一种温和的有机光氧化还原合成方案,通过使广泛的氧化还原活性酯与硫代/硒磺酸盐反应形成 C sp 3 –S/Se 键。前所未有的广泛底物范围和广泛的官能团耐受性推动了合成歧管的力量。
Organocatalytic Transformation of Aldehydes to Thioesters with Visible Light
作者:Yueteng Zhang、Peng Ji、Wenbo Hu、Yongyi Wei、He Huang、Wei Wang
DOI:10.1002/chem.201900932
日期:2019.6.21
A metal‐ and oxidant‐free catalytic method for accessing structurally diverse thioesters from readily accessible, widespread aldehydes, is described. A strategy of a simple organic 9,10‐phenanthrenequinone‐promoted hydrogen atom transfer (HAT) with visible light was successfully implemented to selectively generate acyl radicals without inducing crossover reactivity of thioester products. The preparative
Thiosulfonates were prepared by the iodine oxidative sulfenylation of sulfinates with various disulfides in good yields both in the presence and absence of solvent. One of the important biological applications of sulfenylation is the reaction of cyclic disulfides.
Direct, stereoselective thioglycosylation enabled by an organophotoredox radical strategy
作者:Peng Ji、Yueteng Zhang、Feng Gao、Fangchao Bi、Wei Wang
DOI:10.1039/d0sc04136j
日期:——
transfer pathway have dictated glycosylation development, the direct glycosylation of readily accessible glycosyl donors as radical precursors is particularly appealing because of high radical anomeric selectivity and atom- and step-economy. However, the development of the radical process has been challenging owing to notorious competing reduction, elimination and/or SN side reactions of commonly used
虽然涉及 2e -转移途径的策略决定了糖基化的发展,但由于自由基异头选择性高以及原子和步骤经济性,易于获得的糖基供体作为自由基前体的直接糖基化特别有吸引力。然而,由于常用的不稳定糖基供体的竞争性还原、消除和/或 S N副反应,自由基过程的发展一直充满挑战。在这里,我们介绍了一种有机光催化策略,通过光氧化还原介导的 HAT 催化,糖基溴可以有效地转化为相应的异头自由基,无需过渡金属或导向基团,并实现高度异头选择性。温和的反应条件能够合成具有挑战性的α-1,2-顺式硫代糖苷、各种官能团的耐受性以及常见戊糖和己糖的广泛底物范围,证明了该平台的强大功能。此外,这种通用方法与 sp 2和 sp 3硫亲电子试剂以及总共探测的 50 种底物的后期糖基多样化兼容。