Pd(PPh3)4-catalyzed direct ortho-fluorination of 2-arylbenzothiazoles with an electrophilic fluoride N-fluorobenzenesulfonimide (NFSI)
摘要:
An efficient protocol was developed for regio-selective Pd-catalyzed direct ortho-fluorination of 2-alylbenzo[d]thiazoles using N-fluorobenzenesulfonimide (NFSI) as the F+ source, and L-proline as the crucial promoter. The present method offered a practical route to synthesize valuable fluorinated products, which are of potential importance in the pharmaceutical and agrochemical industries. (C) 2013 The Authors. Published by Elsevier Ltd. All rights reserved.
Synthesis and electronic absorption and fluorescence of 2-arylbenzothiazole derivatives
作者:Lianqing Chen、Chuluo Yang、Suyue Li、Jingui Qin
DOI:10.1016/j.saa.2006.11.038
日期:2007.10
routes. These compounds have been fully characterized by EA, IR, NMR and MS. The electronicabsorption and fluorescence of these compounds have been systematically investigated for the first time. The relationships between their photophysical properties and structures have been discussed. The alteration of absorption and emission wavelengths can be elucidated by Hammett's substituent constants.
Water-promoted Dowex 50W catalyzed highly efficient green protocol for 2-arylbenzothiazole formation
作者:Chhanda Mukhopadhyay、Arup Datta
DOI:10.1002/jhet.9
日期:2009.1
aldehydes were allowed to react in one-pot operation to give 2-aryl-benzothiazoles in excellent yields in the presence of Dowex50W in water. Very high yields coupled with the ease of work-up procedure, formation of no side products, employment of “reusable” catalyst, and “green” synthesis in aqueous medium without maintaining anhydrous reaction conditions are the most important aspects of this methodology
Efficient 2,4,6-trichloro-1,3,5-triazine-catalyzed synthesis of 2-arylbenzothiazoles and bisbenzothiazoles by condensation of 2-aminithiophenol with aldehydes under mild conditions
2,4,6‐Trichloro‐1,3,5‐triazine efficiently catalyzed the condensation reactions between 2‐aminothiophenol and aromatic aldehydes to afford 2‐arylbenzothiazolles in good‐to‐excellent yields. Simple and mild reaction conditions, the use of a cheap catalyst and easy work up, and isolation are notable features of this method. J. Heterocyclic Chem., (2011).
Cooperative bimetallic catalysis is a fundamental approach in modern synthetic chemistry. We report bimetallic cooperative catalysis for the direct decarbonylative heteroarylation of ubiquitous carboxylic acids via acyl C‐O/C‐H coupling. This novel catalytic system exploits the cooperative action of a copper catalyst and a palladium catalyst in decarbonylation, which enables highly chemoselective synthesis
Cross-Dehydrogenative Coupling of Heterocyclic Scaffolds with Unfunctionalized Aroyl Surrogates by Palladium(II) Catalyzed C(sp<sup>2</sup>)-H Aroylation through Organocatalytic Dioxygen Activation
作者:Bhavin V. Pipaliya、Asit K. Chakraborti
DOI:10.1021/acs.joc.7b00226
日期:2017.4.7
carbonyl group of aryl aldehyde and the aryl methane. However, the ease of availability of aryl methanes makes them the most attractive as an aroyl source. A time dependent selective mono- and bis-aroylation can be achieved. The 1,3-diarylpyrimidines exhibited regioselective aroylation of the 2-phenyl moiety irrespective of the absence or presence of any substitutent (electronwithdrawing or electron donating)
通过NHPI的双氧激活,在Pd(II)催化的C(sp 2)-H活化过程中,生物相关的杂环支架与芳基甲烷的芳基化反应进行了脱氢偶联。质谱和基于1 H NMR的动力学同位素效应研究表明,CH键的活化是决定速率的步骤。自由基清除实验表明存在自由基途径。在1等分试样的反应混合物的1 H NMR和用2-氨基硫代苯酚原位捕集揭示芳基甲烷的需氧氧化过程中醛的形成。该反应对于芳酰基源和包括苯并噻唑,苯并恶唑,吡啶,喹喔啉,嘧啶和偶氮芳烃的导向基团的不同变化具有广泛的范围。发现苄基亚甲基部分是芳酰基碳的来源,最优选苄基醚部分,其次是芳基醛和芳基甲烷的羰基。但是,芳基甲烷的易得性使其成为芳酰基源最具吸引力。可以实现时间依赖性的选择性单-和双-芳基化。1 3-二芳基嘧啶表现出2-苯基部分的区域选择性芳酰基化,而与3-苯基部分中是否存在任何取代基(吸电子或供电子)无关。对于不对称的偶氮芳烃,在带有取代基的苯基部分中发生选择性芳酰基化。