27884-09-9Relevant articles and documents
Synthesis of 2-Substituted Benzothio(seleno)phenes and Indoles via Ag-Catalyzed Cyclization/Demethylation of 2-Alkynylthio(seleno)anisoles and 2-Alkynyldimethylanilines
Cai, Tao,Feng, Chengjie,Shen, Fangqi,Bian, Kejun,Wu, Chunlei,Shen, Runpu,Gao, Yuzhen
, p. 653 - 656 (2020/12/23)
An Ag-catalyzed cyclization/demethylation of 2-alkynylthio(seleno)anisoles and 2-alkynyldimethylanilines is described and applied for the construction of valuable benzothio(seleno)phenes as well as indoles. Various 2-substituted benzothio(seleno)phenes and indoles were obtained in good to excellent yields under mild reaction conditions with low catalyst loading. An application of this new method is also exemplified with a concise synthesis of a bioactive molecule precursor. Furthermore, a conceivable reaction mechanism is proposed with supports from isotope-exchange experiments.
Metalated Porous Phenanthroline-Based Polymers as Efficient Heterogeneous Catalysts for Regioselective C?H Activation of Heteroarenes
Tang, Yongquan,Dai, Zhifeng,Wang, Sai,Chen, Fang,Meng, Xiangju,Xiao, Feng-Shou
, p. 2469 - 2474 (2021/08/06)
Direct C?H bond activation of heterocycles as a step-economical and environmentally friendly approach to build the heterobiaryls motifs is highly attractive, but it still has a challenge to design and prepare a cheap and regioselective heterogeneous catal
Infrared Irradiation-Assisted Solvent-Free Pd-Catalyzed (Hetero)aryl-aryl Coupling via C?H Bond Activation
Albano, Gianluigi,Decandia, Gianfranco,Capozzi, Maria Annunziata M.,Zappimbulso, Nicola,Punzi, Angela,Farinola, Gianluca M.
, p. 3391 - 3401 (2021/07/28)
The increasing attention towards environmentally friendly synthetic protocols has boosted studies directed to the development of green and sustainable methods for direct C?H bond arylation of (hetero)arenes. In this context, here the infrared (IR) irradia
C-H Arylation of Thiophenes with Aryl Bromides by a Parts-per-Million Loading of a Palladium NNC-Pincer Complex
Purta, Anggi Eka,Ichii, Shun,Tazawa, Aya,Uozumi, Yasuhiro
supporting information, p. 1634 - 1638 (2020/08/28)
A palladium NNC-pincer complex efficiently catalyzed the direct arylation of thiophene derivatives with extremely low palladium loadings of the order of parts per million. Thus, the reaction of various thiophenes with aryl bromides in the presence of 25-100 mol ppm of chlorido[(2-phenyl-κ- C 2)-9-phenyl-1,10-phenanthroline-κ 2- N, N ′]palladium(II) NNC-pincer complex, K 2CO 3, and pivalic acid in N, N -dimethyl acetamide afforded the corresponding 2- or 5-arylated thiophenes in good to excellent yields. A combination of the present C-H arylation and Hiyama coupling with the same NNC-pincer complex provides an efficient synthesis of unsymmetrical 2,5-thiophenes with catalyst loadings at mol ppm levels.
Nickel-catalyzed and Li-mediated regiospecific C-H arylation of benzothiophenes
Canivet, Jér?me,Grousset, Léonie,Hisler, Ga?lle,Mohr, Yorck,Quadrelli, Elsje Alessandra,Roux, Yoann,Wisser, Florian M.
, p. 3155 - 3161 (2020/06/19)
A nickel-based catalytic system for the regiospecific C2-H arylation of benzothiophene has been established. NiCl2(bpy) is used as a catalyst in combination with LiHMDS as a base in dioxane. The catalytic system is applicable to a variety of functionalized benzothiophenes, as well as other heteroarenes including thiophene, benzodithiophene, benzofuran and selenophene in combination with iodo aryl electrophiles. The role of LiHMDS as a uniquely potent base and a postulated mechanism are discussed. The applicability of this system is finally demonstrated for the synthesis of an intermediate of an active pharmaceutical ingredient.
Transition-Metal-Free Synthesis of Heterobiaryls through 1,2-Migration of Boronate Complex
Paul, Swagata,Das, Kanak Kanti,Manna, Samir,Panda, Santanu
supporting information, p. 1922 - 1927 (2020/02/04)
The synthesis of a diverse range of heterobiaryls has been achieved by a transition-metal-free sp2–sp2 cross-coupling strategy using lithiated heterocycle, aryl or heteroaryl boronic ester and an electrophilic halogen source. The construction of heterobiaryls was carried out through electrophilic activation of the aryl–heteroaryl boronate complex, which triggered 1,2-migration from boron to the carbon atom. Subsequent oxidation of the intermediate boronic ester afforded heterobiaryls in good yield. A comprehensive 11B NMR study has been conducted to support the mechanism. The cross coupling between two nucleophilic cross coupling partners without transition metals reveals a reliable manifold to procure heterobiaryls in good yields. Various heterocycles like furan, thiophene, benzofuran, benzothiophene, and indole are well tolerated. Finally, we have successfully demonstrated the gram scale synthesis of the intermediates for an anticancer drug and OLED material using our methodology.
Decarboxylative Suzuki-Miyaura coupling of (hetero)aromatic carboxylic acids using iodine as the terminal oxidant
Quibell, Jacob M.,Duan, Guojian,Perry, Gregory J.P.,Larrosa, Igor
supporting information, p. 6445 - 6448 (2019/06/07)
A novel methodology for the decarboxylative Suzuki-Miyaura-type coupling has been established. This process uses iodine or a bromine source as both the decarboxylation mediator and the terminal oxidant, thus avoiding the need for stoichiometric amounts of transition metal salts previously required. Our new protocol allows for the construction of valuable biaryl architectures through the coupling of (hetero)aromatic carboxylic acids with arylboronic acids. The scope of this decarboxylative Suzuki reaction has been greatly diversified, allowing for previously inaccessible non-ortho-substituted aromatic acids to undergo this transformation. The procedure also benefits from low catalyst loadings and the absence of stoichiometric transition metal additives.
Arylation synthesis method for novel five-membered aromatic heterocycle and aromatic-ring five-membered aromatic heterocycle
-
Paragraph 0112-0115; 0228-0231; 0236-0239, (2018/07/07)
The invention belongs to the technical field of organic synthesis and in particular relates to an arylation synthesis method for a five-membered aromatic heterocycle or an aromatic-ring five-memberedaromatic heterocycle under the participation of an arylhydrazine derivative serving as a novel arylation reagent. The method comprises the steps: adding a raw material and aroyl hydrazine into a reactor, and carrying out a reaction at 60-100 DEG C for 8-24h under the condition that an oxidant and a transition metal catalyst are added; after the reaction is ended, carrying out suction filtration, extracting a filtrate by using ethyl acetate, carrying out drying to obtain a crude product of a target compound, and carrying out column chromatography on silica gel to obtain a pure product of the target compound. The arylation synthesis method for the five-membered aromatic heterocycle or the aromatic-ring five-membered aromatic heterocycle is scientific and reasonable and has the advantages such as simplicity and convenience in operation, relatively high yield and simplicity in amplification and purification.
Method for synthesizing benzothiophene derivative by catalysis of dihalogenated aromatics by copper
-
Paragraph 0026; 0053, (2018/08/28)
The invention discloses a method for synthesizing a benzothiophene derivative by catalysis of dihalogenated aromatics by copper. According to the invention, a catalyst cuprous iodide with a catalysisamount, a ligand 8-hydroxyquinoline, an auxiliary catalyst cesium carbonate and 1-bromine-2-iodobenzene or its derivative, sulfur powder, and phenylacetylene or its derivative are added in a flask andsubjected to a reaction in pure water at certain temperature, after a certain time, vacuum concentration is carried out, and a product is purified through column chromatography. The method has the advantages of novel raw material and simple operation, and can be used for efficiently preparing the benzothiophene derivative. Compared with the prior art, the method has the advantages of mild reaction condition, simple operation, high yield, safety, low cost, and environmental protection.
Method for synthesizing benzothiophene derivatives from dihaloarene under microwave irradiation under catalysis of copper
-
Paragraph 0030; 0057, (2018/09/08)
The invention discloses a method for synthesizing benzothiophene derivatives from dihaloarene under microwave irradiation under the catalysis of copper. The method comprises the following steps: adding a catalytic amount of a catalyst copper chloride, a ligand 1,10-phenanthroline (1,10-Phen), a cocatalyst potassium hydroxide, 1-bromo-2-iodobenzene and its derivatives, KSCN (potassium thiocyanate),phenylacetylene and pure water, performing a reaction in a microwave reactor at a certain temperature under a certain power for a certain time, performing reduced pressure concentrating, and performing column chromatography purification on the obtained product. The method disclosed in the invention is a method having novel raw materials, being simple to operate and used for efficiently preparingthe benzothiophene derivatives. Compared with the prior art, the method has an obvious faster reaction speed than convectional heating, and has the advantages of mild reaction conditions, simplicity in operation, high yield, safety, low cost and environmental protection.