Direct Carboxylation of Electron‐Rich Heteroarenes Promoted by LiO‐tBu with CsF and [18]Crown‐6. Issue 13 (6th February 2019)

• Record Type: Journal Article
• Authors: Shigeno, Masanori; Hanasaka, Kazuya; Sasaki, Keita; Nozawa‐Kumada, Kanako; Kondo, Yoshinori
• Is Part Of: Chemistry. Volume 25:Issue 13(2019)
• Page Start: 3235
• Page End: 3239
• Publication Date: 2019-02-06
• Subjects: Brønsted base -- carbon dioxide -- carboxylation -- C−H functionalization -- heterocycles; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201805926
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: We herein demonstrate that the combination of LiO‐ t Bu, CsF, and [18]crown‐6 efficiently promotes the direct C−H carboxylation of electron‐rich heteroarenes (benzothiophene, thiophene, benzofuran, and furan derivatives). A variety of functional groups, including methyl, methoxy, halo, cyano, amide, and keto moieties, are compatible with this system. The reaction proceeds via the formation of a tert ‐butyl carbonate species. Abstract : The combination of LiO‐ t Bu, CsF, and [18]crown‐6 efficiently promotes the direct C−H carboxylation of electron‐rich heteroarenes (see scheme; benzothiophene, thiophene, benzofuran, and furan derivatives). A variety of functional groups, including methyl, methoxy, halo, cyano, amide, and keto moieties, are compatible with this system. The reaction proceeds by the formation of a tert ‐butyl carbonate species.