Copper‐Promoted O‐Arylation of the Phenol Side Chain of Tyrosine Using Triarylbismuthines
作者:Adrien Le Roch、Martin Hébert、Alexandre Gagnon
DOI:10.1002/ejoc.202000790
日期:2020.9.7
for the O‐arylation of the sidechain of tyrosine usingtriarylbismuthreagents is reported. The reaction is performed in dichloromethane under oxygen at 50 °C in the presence of pyridine, is promoted by copper diacetate, shows excellent scope and functional group tolerance, and retains the integrity of the chiral center. The reactivity of other amino acids possessing a nucleophilic sidechain under these
Photoredox Mediated Nickel Catalyzed Cross-Coupling of Thiols With Aryl and Heteroaryl Iodides via Thiyl Radicals
作者:Martins S. Oderinde、Mathieu Frenette、Daniel W. Robbins、Brian Aquila、Jeffrey W. Johannes
DOI:10.1021/jacs.5b11244
日期:2016.2.17
Ni-catalyzed cross-couplings of aryl, benzyl, and alkyl thiols with aryl and heteroaryl iodides were accomplished in the presence of an Ir-photoredox catalyst. Highly chemoselective C-Scross-coupling was achieved versus competitive C-O and C-Ncross-couplings. This C-Scross-coupling method exhibits remarkable functional group tolerance, and the reactions can be carried out in the presence of molecular
A mild chemoselective method for S-arylation of cysteine has been developed in an open-flask procedure under metal-free conditions using arenediazoniumsalts in methanol.
<i>peri</i>
‐Xanthenoxanthene (PXX): a Versatile Organic Photocatalyst in Organic Synthesis
作者:Cristofer Pezzetta、Andrea Folli、Oliwia Matuszewska、Damien Murphy、Robert W. M. Davidson、Davide Bonifazi
DOI:10.1002/adsc.202100030
日期:2021.10.19
to be accessible: the β-arylation of cyclic ketones is successful when using a secondary amine as organocatalyst, while cross-coupling reactions of aryl halides with amines and thiols are obtained when using a Ni co-catalyst. Application to the efficient two-step synthesis of the expensive fluoro-tetrahydro-1H-pyrido[4,3-b]indole, a crucial synthetic intermediate for the investigational drug setipiprant
近年来,光催化剂的不断发展,以满足对光氧化还原催化中光物理和氧化还原性能日益增长的需求,设计了复杂的结构或替代策略来获得高度还原或氧化系统。我们在此报告了使用peri- xanthenoxanthene (PXX),一种简单且廉价的染料,作为一种有效的光催化剂。其高度还原的激发态可激活多种底物,从而引发有用的自由基反应。最初证明了基准转换,例如通过有机卤化物的光还原产生的有机自由基添加到自由基陷阱。还显示可以使用更复杂的双催化歧管:β当使用仲胺作为有机催化剂时,环酮的芳基化是成功的,而当使用 Ni 助催化剂时,芳基卤化物与胺和硫醇的交叉偶联反应是成功的。昂贵的氟-四氢-1 H-吡啶并[4,3- b ]吲哚的高效两步合成应用也已得到证实,该吲哚是研究药物塞替吡仑的关键合成中间体。
Copper‐Promoted N‐Arylation of the Imidazole Side Chain of Protected Histidine by Using Triarylbismuth Reagents
作者:Hwai‐Chien Chan、Bianca Bueno、Adrien Le Roch、Alexandre Gagnon
DOI:10.1002/chem.202102186
日期:2021.9.20
The N-arylation of the sidechain of histidine by using triarylbismuthines is reported. The reaction is promoted by copper(II) acetate in dichloromethane at 40 °C under oxygen in the presence of diisopropylethylamine and 1,10-phenanthroline and allows the transfer of aryl groups with substituents at any position of the aromatic ring. The reaction shows excellent functional group tolerance and is applicable
报道了使用三芳基铋对组氨酸侧链进行 N-芳基化。在二异丙基乙胺和 1,10-菲咯啉的存在下,在 40 °C 的二氯甲烷中,乙酸铜 (II) 促进了该反应,并允许在芳环的任何位置具有取代基的芳基转移。该反应显示出优异的官能团耐受性,适用于组氨酸位于 N 端的二肽。在组氨酸占据 C 末端的二肽中观察到组氨酸引导的主链 NH 芳基化。