58861-48-6Relevant articles and documents
Synthesis of Substituted Thiophenes through Dehydration and Heterocyclization of Alkynols
Chen, Lu,Chen, Zebin,Huang, Yubing,Ji, Xiaoliang,Li, Jiaming,Li, Jian,Li, Yibiao,Liu, Qiang,Liu, Yang
supporting information, p. 3555 - 3566 (2022/03/14)
A protocol was described for obtaining a variety of substituted thiophenes with functional potential via metal-free dehydration and sulfur cyclization of alkynols with elemental sulfur (S8) or EtOCS2K in moderate-to-good yields. The method provides the base-free generation of a trisulfur radical anion (S3?-) and its addition to alkynes as an initiator. This research broadens the applications of S3?-in the synthesis of sulfur-containing heterocycles.
Preparation method of canagliflozin intermediate 2-(4-fluorophenyl) thiophene
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Paragraph 0032-0066, (2021/01/04)
The invention relates to a preparation method of canagliflozin intermediate 2-(-4fluorophenyl) thiophene. The method comprises the following steps of: (1) enabling 2-bromothiophene to react with magnesium chips in a THF solvent to generate 2-thienyl magnesium bromide Grignard liquid; (2) carrying out catalytic Kumada coupling reaction on the 2-thienyl magnesium bromide Grignard liquid and p-fluorobromobenzene in the presence of a nickel or palladium complex as a catalyst, so as to obtain the 2-(-4fluorophenyl) thiophene. The method is good in product quality, high in yield, mild in reaction condition, simple to operate and easy to industrialize.
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.