63676-27-7Relevant 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 (2021)
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
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.
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.
Trithiocarbonate Anion as a Sulfur Source for the Synthesis of 2,5-Disubstituted Thiophenes and 2-Substituted Benzo[ b]thiophenes
Paix?o, Douglas B.,Rampon, Daniel S.,Salles, Helena D.,Soares, Eduardo G. O.,Bilheri, Filipe N.,Schneider, Paulo H.
, p. 12922 - 12934 (2020/11/26)
The trithiocarbonate anion (CS32-) was generated in situ from CS2 and KOH in dimethyl sulfoxide by a simple method and used as a novel synthetic equivalent of the S2- synthon for the synthesis of 2,5-disubstituted thiophenes from 1,3-butadiynes. Additionally, this system was employed for the metal-free synthesis of 2-substituted benzo[b]thiophenes from 2-haloalkynyl (hetero)arenes. These compounds were obtained from a cheap and readily available sulfur source in moderate to good yields, with good functional group tolerance.
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.
Method for synthesizing benzothiophene derivative by catalysis of dihalogenated aromatics by copper
-
Paragraph 0026; 0050, (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; 0054, (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.
Ag(I)-C-H Activation Enables Near-Room-Temperature Direct α-Arylation of Benzo[ b]thiophenes
Colletto, Chiara,Panigrahi, Adyasha,Fernández-Casado, Jaime,Larrosa, Igor
supporting information, p. 9638 - 9643 (2018/07/21)
The first example of near-room-temperature α-arylation of benzo[b]thiophenes is reported. The discovery rests on the observation of a switch in α-/β-regioselectivity at different loadings of Pd2(dba)3·CHCl3 in the coupling between benzo[b]thiophene and 4-iodotoluene. We show that this unprecedented regioselectivity switch is driven by a Ag(I)-mediated C-H activation at the α-C-H position, which becomes the dominant mode of reactivity at low concentrations of Pd. Competition experiments, kinetic studies, KIE, and D/H scrambling experiments have been carried out supporting this mechanism.
Visible light mediated desilylative C(sp2)-C(sp2) cross-coupling reactions of arylsilanes with aryldiazonium salts under Au(i)/Au(iii) catalysis
Chakrabarty, Indradweep,Akram, Manjur O.,Biswas, Suprakash,Patil, Nitin T.
, p. 7223 - 7226 (2018/07/03)
Desilylative C(sp2)-C(sp2) cross-coupling reactions of arylsilanes with aryldiazonium salts under Au(i)/photoredox catalysis have been reported. The addition of Cu-salts as catalysts was found to be crucial for the success of this tr
