40115-03-5Relevant articles and documents
Method for catalytically synthesizing benzothiazole compound by using copper complex
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Paragraph 0056-0067, (2021/09/22)
The invention relates to a method for catalytically synthesizing benzothiazole compounds by using a copper complex, which is characterized in that a copper complex containing ortho-carborane Schiff base ligand is used as a catalyst to form aldehydes. 2 - Bromoaniline and sodium sulfide are used as raw materials, and the reaction is carried out at room temperature to obtain a benzothiazole compound. Compared with the prior art, the copper complex catalytic aldehyde, 2 -bromoaniline and sodium sulfide (Na) containing the ortho-carborane Schiff base ligand are utilized. 2 Multiple components of S) react to prepare benzothiazole compounds, and the catalyst is low in dosage, mild in reaction conditions, high in reaction rate, high in yield, wide in substrate range, cheap and accessible in raw materials and wide in application prospect in industry.
Development of a Quinolinium/Cobaloxime Dual Photocatalytic System for Oxidative C-C Cross-Couplings via H2Release
Li, Jianbin,Huang, Chia-Yu,Han, Jing-Tan,Li, Chao-Jun
, p. 14148 - 14158 (2021/11/27)
Designing molecular photocatalysts for potent photochemical reactivities ranks among the most challenging but rewarding endeavors in synthetic photochemistry. Herein, we document a quinoline-based organophotoredox catalyst, 2,4-bis(4-methoxyphenyl)quinoli
Photoelectrochemical cross-dehydrogenative coupling of benzothiazoles with strong aliphatic C-H bonds
Capaldo, Luca,Quadri, Lorenzo L.,Merli, Daniele,Ravelli, Davide
, p. 4424 - 4427 (2021/05/10)
A photoelectrochemical strategy for the cross-dehydrogenative coupling of unactivated aliphatic hydrogen donors (e.g.alkanes) with benzothiazoles is reported. We used tetrabutylammonium decatungstate as the photocatalyst to activate strong C(sp3)-H bonds in the chosen substrates, while electrochemistry scavenged the extra electrons.
ZnO-NPs catalyzed condensation of 2-aminothiophenol and aryl/alkyl nitriles: Efficient green synthesis of 2-substituted benzothiazoles
Dhawale, Kiran D.,Ingale, Ajit P.,Shinde, Sandeep V.,Thorat, Nitin M.,Patil, Limbraj R.
, p. 1588 - 1601 (2021/03/18)
The synthesis of 2-substituted benzothiazoles has been described using ZnO-nanoparticles as a catalyst. The condensation of 2-aminothiophenol and aryl/alkyl nitriles resulted in the formation of various 2-substituted benzothiazoles under solvent-free reaction conditions. The library of 2-substituted benzothiazoles has been synthesized in good to excellent yield. The reaction has shown a wide range of functional group compatibility for both varyingly substituted 2-aminothiophenols and nitriles. The protocol has many advantages such as faster reaction rate, mild reaction conditions, various functional group compatibility, excellent yield, solvent-free reaction conditions, easy recovery of materials, and excellent catalyst recyclability, among others. The various advantages of this protocol make it a more feasible, economical, and environmentally benign process.
Visible-Light-Mediated Alkenylation of Alkyl Boronic Acids without an External Lewis Base as an Activator
Yue, Fuyang,Dong, Jianyang,Liu, Yuxiu,Wang, Qingmin
, p. 2477 - 2481 (2021/04/05)
Herein we report a protocol for the direct visible-light-mediated alkenylation of alkyl boronic acids at room temperature without an external Lewis base as an activator, and we propose a mechanism involving benzenesulfinate activation of the alkyl boronic acids. The protocol permits the efficient functionalization of a broad range of cyclic and acyclic primary and secondary alkyl boronic acids with various alkenyl sulfones. We demonstrated its utility by preparing or functionalizing several pharmaceuticals and natural products.
Late-Stage Alkylation of N-Containing Heteroarenes Enabled by Homolysis of Alkyl-1,4-dihydropyridines under Blue LED Irradiation
Chen, Xiaoping,Luo, Xiaosheng,Wang, Kaiqian,Liang, Feng,Wang, Ping
supporting information, p. 733 - 737 (2021/04/15)
Alkylated heteroarenes are widely found in bioactive molecules and pharmaceuticals. Therefore, there is great interest in developing a chemoselective alkylation of heteroarenes under mild conditions, particularly during a late-stage functionalization step for the purpose of rapid derivatization. Herein, we introduce an efficient visible-light-promoted C-H alkylation of nitrogen-containing heteroarenes by using C4-Alkyl 1,4-dihydropyridines (DHPs) as radical precursors at ambient temperatures. A broad scope of heteroarenes, such as 4-hydroxyquinazoline and its derivatives, including those bearing electron-donating or electron-withdrawing groups, can be successfully alkylated in good yields by using various C4-Alkyl DHPs.
Visible-light-promoted photocatalyst-free alkylation and acylation of benzothiazoles
Jiang, Pengxing,Liu, Li,Tan, Jiajing,Du, Hongguang
supporting information, p. 4487 - 4491 (2021/05/31)
Herein we report a protocol for the visible-light-mediated alkylation/acylation reaction of benzothiazoles. Alkyl/acyl substituted Hantzsch esters are easily prepared and rationally used as radical precursors. In the presence of BF3·Et2O and Na2S2O8, various benzothiazole derivatives were readily obtained in good yields. Our user-friendly protocol can proceed by simple irradiation with blue LEDs (λ = 465 nm) and without the assistance of external photocatalysts. The reaction is also characterized by mild conditions and scalability, thus offering an alternative and efficient tool for the synthesis of 2-functionalized benzothiazoles.
Iodine-promoted ring-opening methylation of benzothiazoles with dimethyl sulfite
Guo, Ying-Qiong,Chen, Fan,Deng, Chen-Liang,Zhang, Xing-Guo
supporting information, p. 1923 - 1926 (2021/03/02)
A halogen-bond promoted ring-opening methylation of benzothiazoles has been developed using dimethyl sulphite as a methylating reagent in the presence of a base. This approach represents a simple and efficient synthesis ofN-methyl-N-(o-methylthio)phenyl amides, and features direct construction of both N-Me and S-Me bonds in a one-pot reaction through the decomposition of easily prepared benzothiazoles.
Direct functionalization of quinoxalin-2(1H)-one with alkanes: C(sp2)-H/C(sp3)-H cross coupling in transition metal-free mode
Dagar, Neha,Raha Roy, Sudipta,Singh, Swati
, p. 5383 - 5394 (2021/06/28)
Considering the significance of pharmaceutically important heterocycles, efficient and highly versatile protocols for the functionalization of diverse heterocycles with easily accessible feedstock are crucial. Here, we have reported selective alkylation of quinoxalin-2(1H)-one with a broad class of hydrocarbons having different C(sp3)-H bonds with varying bond strengths using di-tert-butyl peroxide (DTBP) as an alkoxyl radical mediator for hydrogen atom transfer (HAT). This dehydrogenative coupling approach utilizes feedstock chemicals such as cycloalkanes, cyclic ethers and alkyl arenes as coupling partners. This protocol exhibits good functional group compatibility and selectivity regarding both heterocycles and unactivated alkanes. Moreover, this methodology allows functionalization of relatively strong C-H bonds of adamantane and exclusive selectivity towards 3° C(sp3)-H bonds is observed. We also illustrate the applicability of this C(sp2)-H/C(sp3)-H cross-coupling for practical access to bioactive pharmaceuticals.
Time-Resolved EPR Revealed the Formation, Structure, and Reactivity of N -Centered Radicals in an Electrochemical C(sp3)-H Arylation Reaction
Alhumade, Hesham,Gao, Renfei,Huang, Cunlong,Lei, Aiwen,Liu, Yichang,Liu, Zhao,Qi, Xiaotian,Shi, Biyin,Wang, Shengchun
supporting information, p. 20863 - 20872 (2021/12/14)
Electrochemical synthesis has been rapidly developed over the past few years, while a vast majority of the reactions proceed through a radical pathway. Understanding the properties of radical intermediates is crucial in the mechanistic study of electroche
