Room-temperature cobalt-catalyzed arylation of aromatic acids: overriding the ortho-selectivity via the oxidative assembly of carboxylate and aryl titanate reagents using oxygen
作者:Kun-Ming Liu、Rui Zhang、Xin-Fang Duan
DOI:10.1039/c5ob02496j
日期:——
A room temperature phosphine or NHC ligand-free cobalt-catalyzed arylation of (hetero)aromatic acids has been developed.
Intramolecular Aromatic C–H Acyloxylation Enabled by Iron Photocatalysis
作者:Siqi Xia、Kunjun Hu、Chuanhu Lei、Jian Jin
DOI:10.1021/acs.orglett.0c00002
日期:2020.2.21
protocol for the intramolecular aromatic C-H oxygenation of 2-biphenylcarboxylic acids has been achieved via iron photocatalysis. The 2-biphenylcarboxylic acids with a diverse array of substituents at both phenyl rings could furnish the oxygenation products in good to excellent yields. We speculate that the aryl carboxylate-iron(III) complexes should generate the aroyloxy radicals and iron(II) upon visible
The present invention relates to a compound of formula I
wherein R
1
, R
2
, and Ar are as defined herein or to a pharmaceutically acceptable acid addition salt, to a racemic mixture, or to its corresponding enantiomer and/or optical isomer thereof. These compounds and their pharmaceutical compositions are useful in the treatment of neurological and neuropsychiatric disorders.
General and Practical Carboxyl-Group-Directed Remote CH Oxygenation Reactions of Arenes
作者:Yang Wang、Anton V. Gulevich、Vladimir Gevorgyan
DOI:10.1002/chem.201303511
日期:2013.11.18
Two methods for remote aromatic CHoxygenationreactions, have been developed. Method 1, the Cu‐catalyzed oxygenationreaction, is highly efficient for cyclization of electron‐neutral and electron‐rich biaryl carboxylic acids into 3,4‐benzocoumarins. Method 2, the K2S2O8‐mediated oxygenationreaction, is more general and practical for cyclization of substrates with electron‐donating and ‐withdrawing
已经开发了两种用于远程芳族 C H 氧化反应的方法。方法 1,即 Cu 催化的氧化反应,对于将电子中性和富电子的联芳基羧酸环化为 3,4-苯香豆素非常有效。方法 2,K 2 S 2 O 8介导的氧化反应,对于具有给电子和吸电子基团的底物的环化更为通用和实用(见方案)。
<i>ortho</i>
‐C−H Arylation of Benzoic Acids with Aryl Bromides and Chlorides Catalyzed by Ruthenium
作者:Agostino Biafora、Thilo Krause、Dagmar Hackenberger、Florian Belitz、Lukas J. Gooßen
DOI:10.1002/anie.201607270
日期:2016.11.14
of catalytic amounts of [(p‐cym)RuCl2]2/PEt3⋅HBF4, K2CO3 as the base, and NMP as the solvent efficiently mediates the ortho‐C−H arylation of benzoic acids with aryl bromides at 100 °C. Replacing the phosphine ligand with the amino acid dl‐pipecolinic acid enables the analogous transformation with aryl chlorides. The key advantage of this broadly applicable transformation is the use of an inexpensive
包括催化量的一种系统,[(p -cym)的RuCl 2 ] 2 / PET 3 ⋅HBF 4,K 2 CO 3作为碱,和NMP作为溶剂有效地介导了邻位的苯甲酸与-C-H芳基化100°C时的芳基溴化物。用氨基酸dl-胡椒碱取代膦配体可实现与芳基氯化物的类似转化。这种广泛适用的转化方法的主要优点是使用廉价的钌催化剂,结合简单的羧酸盐作为导向基团,可以将其无痕除去或用作脱羧ipso的锚定点 换人。