25936-01-0Relevant academic research and scientific papers
Synthesis of Benzo[b]thiophenes through Rhodium-Catalyzed Three-Component Reaction using Elemental Sulfur
Moon, Sanghun,Kato, Moena,Nishii, Yuji,Miura, Masahiro
supporting information, p. 1669 - 1673 (2020/03/23)
A benzo[b]thiophene synthesis by Rh-catalyzed three-component coupling reaction of arylboronic acids, alkynes, and elemental sulfur (S8) is developed. A notable feature of this protocol is that the thienannulation (thiophene annulation) proceeds with high regioselectivity via the sequential alkyne insertion, C?H activation, and then sulfur atom transfer to the metallacycle intermediate. In a similar manner, dibenzothiophenes can be synthesized from the parent biarylboronic acids and S8. (Figure presented.).
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.
Photopromoted Entry to Benzothiophenes, Benzoselenophenes, 3H-Indoles, Isocoumarins, Benzosultams, and (Thio)flavones by Gold-Catalyzed Arylative Heterocyclization of Alkynes
Alcaide, Benito,Almendros, Pedro,Busto, Eduardo,Herrera, Fernando,Lázaro-Milla, Carlos,Luna, Amparo
supporting information, p. 2640 - 2652 (2017/08/16)
Visible light-promoted and gold-photoredox-catalyzed reactions of heteroatom (N, S, Se, O) tethered alkynes with arenediazonium salts selectively proceeded to build vicinal diaryl-substituted 2H-benzo[e][1,2]thiazine 1,1-dioxides (benzosultams), benzoselenophenes, benzothiophenes, 4H-chromen-4-ones (flavones), 3H-indoles, 1H-isochromen-1-ones (isocoumarins), and 4H-thiochromen-4-ones (thioflavones). Moreover, the utility of functionalized 3H-indoles as precursors for further elaboration has been demonstrated with the switchable and facile preparation of 1H-indoles, 2-oxindoles, and 3-oxindolines. (Figure presented.).
SYNTHESIS AND REARRANGEMENT OF DIARYL-HYDROXY-BENZOTHIOPHENS. A NEW SYNTHESIS OF 2,3-DIARYL-BENZOTHIOPHENS
Leardini, Rino,Tundo, Antonio,Zanardi, Giuseppe,Pedulli, Gianfranco
, p. 3381 - 3382 (2007/10/02)
The synthesis of some 2-hydroxy-2(H)-3,3-diaryl- and 3-hydroxy-3(H)-2,2-diaryl-benzothiophens (4) and (7) respectively is described; by acidic treatment these compounds readily rearrange to 2,3-diaryl-benzothiophens (5) in almost quantitative yields
