Electrophotocatalytic C–H Functionalization of Ethers with High Regioselectivity
作者:He Huang、Zack M. Strater、Tristan H. Lambert
DOI:10.1021/jacs.9b11472
日期:2020.1.29
The highly regioselective electrophotocatalytic C-H functionalization of ethers is described. These reactions are catalyzed by a trisaminocyclopropenium (TAC) ion in a mild electrochemical potential with visible light irradiation. Ethers undergo oxidant-free coupling with isoquinolines, alkenes, alkynes, pyrazoles, and purines with typically high regioselectivity for the less-hindered α-position. The
O–H hydrogen bonding promotes H-atom transfer from α C–H bonds for C-alkylation of alcohols
作者:Jenna L. Jeffrey、Jack A. Terrett、David W. C. MacMillan
DOI:10.1126/science.aac8555
日期:2015.9.25
alcohols is selectively induced by using an H-bonding catalyst to bind the hydroxyl group of the alcohol. The adjacent C-H bonds now become susceptible to a reaction accelerated by another pair of catalysts. In combination, the trio of catalysts promotes C-C bond formation at the alcohol C within an array of competing sites. Science, this issue p. 1532 Hydrogen bonding confers siteselectivity in a carbon-carbon
三重奏有助于激活醇中的 CH 键酶可以通过位置良好的 H 键激活分子的特定部分来加速化学反应。杰弗里等人。在合成环境中展示氢键的力量。在这里,醇的 C 中心的反应性是通过使用 H 键催化剂来结合醇的羟基而选择性地诱导的。相邻的 CH 键现在变得容易受到另一对催化剂加速的反应的影响。组合起来,这三种催化剂促进了在一系列竞争位点内的醇 C 处形成 CC 键。科学,这个问题 p。1532 氢键在醇和烯烃之间的碳-碳键形成反应中赋予位点选择性。在存在多个潜在的氢原子供体和受体的情况下,从有机分子转移氢原子的效率和选择性通常难以控制。在这里,我们描述了一种催化活化模式的机理评估,该模式通过氢原子转移机制实现了醇与丙烯酸甲酯的高选择性光氧化还原 α-烷基化/内酯化。我们的研究表明,在烯丙基、苄基、α-C=O 和 α-醚 C-H 键存在的情况下,四正丁基磷酸铵在提高醇中 α C-H 键的选择性方面具有特
作者:Jinhong Chen、Hao Wang、Craig S. Day、Ruben Martin
DOI:10.1002/anie.202212983
日期:2022.12.12
A Ni-catalyzed site-selective intermolecularC(sp3)−H amidation has been developed. This protocol is characterized by its mild conditions, broad substrate scope, and excellent chemo- and site-selectivity, thus unlocking a complementary technique to conventional C(sp3)−N bond-forming reactions for accessing amine architectures from simple building blocks.
products. Its light-absorption properties make it useful for the design of functional molecules. However, versatile synthesis methods have not yet been reported. In this report, we present a versatile synthetic method for pseudoindoxyls using the direct S0 → Tn transition under visiblelight irradiation. We also discuss the application of pseudoindoxyls as photocatalysts.
假吲哚酚是在各种天然产物中发现的部分骨架。其光吸收特性使其可用于功能分子的设计。然而,通用的合成方法尚未见报道。在本报告中,我们提出了一种在可见光照射下利用直接 S 0 → T n跃迁合成假吲哚酚的通用方法。我们还讨论了假吲哚酚作为光催化剂的应用。
Electroorganic chemistry. 134. Facile electroreduction of methyl esters and N,N-dimethylamides of aliphatic carboxylic acids to primary alcohols
In the presence of t-BuOH, methyl esters and N,N-dimethylamides of aliphatic carboxylic acids are electroreduced at a Mg cathode to the corresponding primary alcohols. In the presence of t-BuOD instead of t-BuOH, the electroreduction of the esters gives the corresponding 1,1-dideuterated alcohol. In all cases, the yields are excellent.