1310492-93-3Relevant articles and documents
Regioselective, Solvent- and Metal-Free Chalcogenation of Imidazo[1,2-a]pyridines by Employing I2/DMSO as the Catalytic Oxidation System
Rafique, Jamal,Saba, Sumbal,Rosário, Alisson R.,Braga, Antonio L.
, p. 11854 - 11862 (2016)
Highly efficient molecular-iodine-catalyzed chalcogenations (S and Se) of imidazo[1,2-a]pyridines were achieved by using diorganoyl dichalcogenides under solvent-free conditions. This approach afforded the desired products that had been chalcogenated regioselectively at the C3 position in up to 96 % yield by using DMSO as an oxidant, in the absence of a metal catalyst, and under an inert atmosphere. This mild, green approach allowed the preparation of different types of chalcogenated imidazo[1,2-a]pyridines with structural diversity. Furthermore, the current protocol was also extended to other N-heterocyclic cores.
Sequential Regioselective Diorganochalcogenations of Imidazo[1,2- a]pyrimidines Using I2/H3PO4 in Dimethylsulfoxide
Broggi, Julie,Kabri, Youssef,Obah Kosso, Anne Roly,Redon, Sébastien,Vanelle, Patrice
, p. 3071 - 3081 (2020)
The dichalcogenation of imidazoheterocycles led to the first functionalization of imidazo[1,2-a]pyrimidine cores on the C6-position. The methodology, involving iodine/dimethylsulfoxide oxidation of diaryldichalcogenides, started with C3-chalcogenation, fo
Metal-free regioselective C-H chalcogenylation of coumarins/(hetero)arenes at ambient temperature
Song, Zengqiang,Ding, Chaochao,Wang, Shaoli,Dai, Qian,Sheng, Yaoguang,Zheng, Zhilong,Liang, Guang
supporting information, p. 1847 - 1850 (2020/02/22)
A novel, practical and metal-free approach for the regioselective selenation of coumarins employing (bis(trifluoroacetoxy)iodo)benzene (PIFA) at room temperature is presented. The developed method is suitable for a wide substrate scope and affords 3-selen
Direct, Metal-free C(sp2)?H Chalcogenation of Indoles and Imidazopyridines with Dichalcogenides Catalysed by KIO3
Rafique, Jamal,Saba, Sumbal,Franco, Marcelo S.,Bettanin, Luana,Schneider, Alex R.,Silva, Lais T.,Braga, Antonio L.
supporting information, p. 4173 - 4180 (2018/02/06)
Herein, we report a greener protocol for the synthesis of 3-Se/S-indoles and imidazo[1,2-a]pyridines through direct C(sp2)?H bond chalcogenation of heteroarenes with half molar equivalents of different dichalcogenides, using KIO3 as a non-toxic, easy-to-handle catalyst and a stoichiometric amount of glycerol. The reaction features are high yields, based on atom economy, easy performance on gram-scale, metal- and solvent-free conditions as well as applicability to different types of N-heteroarenes.
NIS/TBHP Induced Regioselective Selenation of (Hetero)Arenes via Direct C?H Functionalization
Ding, Chaochao,Yu, Yuanzu,Yu, Qiongli,Xie, Zixin,Zhou, Yan,Zhou, Jianmin,Liang, Guang,Song, Zengqiang
, p. 5397 - 5401 (2018/11/23)
A simple and efficient method for the regioselective selenation of (hetero)arenes via direct C?H functionalization has been established using NIS and TBHP. The present protocol is compatible with different functional groups, and suitable for various (hete
NH4I-catalyzed chalcogen(S/Se)-functionalization of 5-membered N-heteroaryls under metal-free conditions
Bettanin, Luana,Saba, Sumbal,Doerner, Carlos V.,Franco, Marcelo S.,Godoi, Marcelo,Rafique, Jamal,Braga, Antonio L.
, p. 3971 - 3980 (2018/06/12)
Herein, we described the NH4I-catalyzed C–H bond chalcogenation of N-heteroaryls in the presence of a minimum amount of DMSO/H2O/acetic acid as additives (2.5/2.5/1 M equiv., respectively), under metal-free conditions. Under optimized conditions, a wide variety of sulfenyl/selenyl imidazo[1,2-α]pyridines were prepared in very good yields. Moreover, the present approach was also highly efficient for the chalcogenation of different 5-membered N-heteroaryls, e.g., indole, imidazothiazole, indazole and imidazopyrimidine derivatives.
Rose Bengal catalysed photo-induced selenylation of indoles, imidazoles and arenes: A metal free approach
Saba, Sumbal,Rafique, Jamal,Franco, Marcelo S.,Schneider, Alex R.,Espíndola, Leandro,Silva, Dagoberto O.,Braga, Antonio L.
supporting information, p. 880 - 885 (2018/02/19)
In this report, the highly efficient Rose Bengal-catalysed C(sp2)-H selenylation of indoles, imidazoles and arenes was achieved using a half molar equiv. of diorganoyl diselenides. This metal-free, photo-induced protocol resulted in selenylated
An efficient and clean CuI-catalyzed chalcogenylation of aromatic azaheterocycles with dichalcogenides
Li, Zhen,Hong, Jianquan,Zhou, Xigeng
supporting information; experimental part, p. 3690 - 3697 (2011/06/17)
A highly efficient and environmentally friendly method for catalytic chalcogenylation of imidazopyridines, imidazopyrimidines, indoles, and pyrrolo[2,3-b]pyridines with dichalcogenides has been developed by using CuI as catalyst under air. The reactions proceed smoothly to give the desired products in moderate to excellent yields, without the presence of other additive.
