Chemoselective Catalytic Dehydrogenative Cross-Coupling of 2-Acylimidazoles: Mechanistic Investigations and Synthetic Scope was written by Tanaka, Tsukushi;Hashiguchi, Kayoko;Tanaka, Takafumi;Yazaki, Ryo;Ohshima, Takashi. And the article was included in ACS Catalysis in 2018.Application In Synthesis of 2,5-Dimethylthiophene The following contents are mentioned in the article:
Chemoselective iron-catalyzed dehydrogenative cross-coupling using 2-acylimidazoles is described. The addition of a phosphine oxide ligand substantially facilitated the generation of tert-butoxy radicals from di-tert-Bu peroxide, allowing for efficient benzylic C-H bond cleavage under mild conditions. Extensive mechanistic studies revealed that the enolization of 2-acylimidazole proceeded through dual iron catalyst activation, followed by subsequent chemoselective cross-coupling with a benzyl radical over an undesired benzyl radical-derived homocoupling dimer that inevitably formed in earlier reported conditions. A variety of alkylarenes, aliphatic alkane, and functionalized 2-acylimidazoles were applicable, demonstrating the synthetic utility of the present catalysis. Contiguous all-carbon quaternary carbons were constructed through dehydrogenative cross-coupling. The catalytic chemoselective activation of 2-acylimidazole over bidentate coordinative and much more acidic malonate diester was particular noteworthy. Catalytic oxidative cross-enolate coupling of two distinct carboxylic acid equivalent was also achieved using acetonitrile as a coupling partner. This study involved multiple reactions and reactants, such as 2,5-Dimethylthiophene (cas: 638-02-8Application In Synthesis of 2,5-Dimethylthiophene).
2,5-Dimethylthiophene (cas: 638-02-8) belongs to benzothiophene derivatives. Benzothiophene finds use in research as a starting material for the synthesis of larger, usually bioactive structures. It is found within the chemical structures of pharmaceutical drugs such as zileuton, raloxifene, and sertaconazole, and also BTCP.Application In Synthesis of 2,5-Dimethylthiophene
Referemce:
Benzothiophene – Wikipedia,
Benzothiophene | C8H6S – PubChem