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-Arylamines Coupled with Aldehydes, Ketones, and Imines by Means of Photocatalytic Proton-Coupled Electron Transfer
作者:Qing Xia、Hao Tian、Jianyang Dong、Yi Qu、Lili Li、Hongjian Song、Yuxiu Liu、Qingmin Wang
DOI:10.1002/chem.201801886
日期:2018.7.2
A photoredox‐catalyzed umpolung strategy for coupling reactions between aldehydes, ketones, imines, and N‐arylamines is reported. These reactions proceed by a Brønstedacid‐activated proton‐coupled electron transfer pathway, and the protocol was used to synthesize a broad scope of 1,2‐amino alcohols and vicinal diamines, both of which are common motifs in biologically active natural products, pharmaceutically
A Visible Light Photocatalytic Cross-Dehydrogenative Coupling/Dehydrogenation/6π-Cyclization/Oxidation Cascade: Synthesis of 12-Nitroindoloisoquinolines from 2-Aryltetrahydroisoquinolines
A visiblelight‐induced photocatalytic dehydrogenation/6π‐cyclization/oxidation cascade converts 1‐(nitromethyl)‐2‐aryl‐1,2,3,4‐tetrahydroisoquinolines into novel 12‐nitro‐substituted tetracyclic indolo[2,1‐a]isoquinoline derivatives. Various photocatalysts promote the reaction in the presence of air and a base, the most efficient being 1‐aminoanthraquinone in combination with K3PO4. Further, the
可见光诱导的光催化脱氢/6π环化/氧化级联反应将1-(硝基甲基)-2-芳基-1,2,3,4-四氢异喹啉转化为新型的12-硝基取代的四环吲哚[2,1- a ]异喹啉衍生物。各种光催化剂可在空气和碱的存在下促进反应,最有效的是将1-氨基蒽醌与K 3 PO 4结合使用。此外,通过扩展单锅程序与前述的光催化交叉脱氢偶联反应,可直接从C1未官能化的2‐芳基1,2,3,4‐四氢异喹啉中直接获得12‐硝基吲哚异喹啉产物,从而产生四级联反应转型。
Asymmetric Aerobic Oxidative Cross-Coupling of Tetrahydroisoquinolines with Alkynes
An efficient asymmetric aerobic oxidation of tetrahydroisoquinolines with terminal alkynes was realized under mild reaction conditions using O2 as the sole oxidant. A chiral N,N′-dioxide/zinc(II)/iron(II) bimetallic cooperative catalytic system proves to be efficient for the formation of various α-alkynyl substituted tetrahydroisoquinolines in good to excellent yields and enantioselectivities. A primary
Radical alkylation of C(sp<sup>3</sup>)–H bonds with diacyl peroxides under catalyst-free conditions
作者:Hao Tian、Wentao Xu、Yuxiu Liu、Qingmin Wang
DOI:10.1039/c9cc08056b
日期:——
Herein, we describe a protocol for alkylation reactions of C(sp3)–H bonds with diacylperoxides by means of a process involving cross-coupling between an alkyl radical and an α-aminoalkyl radical. The mild, catalyst- and additive-free conditions make this protocol superior to previously reported C(sp3)–H alkylation strategies. The protocol was applied to 1,2,3,4-tetrahydroisoquinolines and a tetrahydro-β-carboline
quantum dots (QDs) can activate α-C-H bond of THF via forming QDs/THF conjugates. Under visible light irradiation, the resultant alkoxyalkyl radical directly engages in radical cross-coupling with α-amino radical from amino C-H bonds or radicaladdition with alkene or phenylacetylene, respectively. In contrast to stoichiometric oxidant or hydrogenatom transfer reagents required in previous studies, the