Ruthenium-Catalyzed C–H Arylation of Diverse Aryl Carboxylic Acids with Aryl and Heteroaryl Halides
作者:Liangbin Huang、Daniel J. Weix
DOI:10.1021/acs.orglett.6b02862
日期:2016.10.21
ligated to tricyclohexylphosphine or di-tert-butylbipyridine catalyzes the arylation of carboxylic acids with diverse arylhalides (iodide, bromide, and triflate; aryl and heteroaryl). In addition, arylations with 2-iodophenol formed benzochromenones, carboxylate was shown to be a stronger donor than an amide, and the arylation of a pyridine carboxylate was demonstrated. Stoichiometric studies demonstrated
Highly para-selective palladium-catalyzed direct arylation of phenols with aryl iodides was demonstrated by taking advantage of the formal inverse direct arylation strategy. A series of 4-aryl phenols were synthesised by employing water as a “green” solvent under mild reaction conditions.
<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。
Rhodium‐Catalyzed
<i>ortho</i>
‐Arylation of (Hetero)aromatic Acids
作者:Philip Weber、Christian K. Rank、Enis Yalcinkaya、Marco Dyga、Tim van Lingen、Rochus Schmid、Frederic W. Patureau、Lukas J. Gooßen
DOI:10.1002/adsc.201900596
日期:2019.9.3
Rhodium acetate effectively promotes the carboxylate‐directed ortho‐arylation of (hetero)aromatic carboxylates with aryl bromides. The main advantage of this phosphine‐free, redox‐neutral method arises from its efficiency in assembling biologically meaningful electron‐rich arylpyridines, which are problematic substrates in known C−H arylations using Pd, Ru, and Ir catalysts.