A metal‐free aerobicoxidative C–H sulfenylation of aryl‐fused cyclic amines with various thiols was developed with excellent functional compatibility. While flavin I catalyzed the C–H sulfenylation of indolines to afford 3‐sulfenylindoles, flavin II enabled transformations resulting in substitution at the position para to the N atom on the aryl ring to obtain 6‐sulfenylquinolines.
Iodine-Catalyzed Mono- and Disulfenylation of Indoles in PEG<sub>400</sub>
through a Facile Microwave-Assisted Process
作者:Rajjakfur Rahaman、Pranjit Barman
DOI:10.1002/ejoc.201701293
日期:2017.11.16
An iodine-catalyzed versatile green method for the synthesis of mono- and 2,3-bis-sulfenyl indoles has been presented. Various indoles can react with alkyl or aryl sodiumsulfinates using hydrogen peroxide as an oxidizing agent in PEG400 under microwave conditions. This simple method enabled the rapid synthesis of mono- and 2,3-bis-sulfenylindoles with good to excellent yields under metal free conditions
A method which avoids metal and halogen for the synthesis of 3-arylthioindoles from indoles and diaryl disulfides using ammonium persulfate in methanol has been presented. Moreover, double C–H sulfenylation of indoles at 2 and 3-positions has also been achieved using iodine and ammonium persulfate.
Flavin–iodine coupled organocatalysis for the aerobic oxidative direct sulfenylation of indoles with thiols under mild conditions
作者:Ryoma Ohkado、Tatsuro Ishikawa、Hiroki Iida
DOI:10.1039/c8gc00117k
日期:——
A unique coupled redox organocatalysis system using flavin and iodine catalysts efficiently promoted the metal-free aerobic oxidative direct sulfenylation of indoles with thiols at ambient temperature without any sacrificial reagents, except environmentally benign molecular oxygen. Biomimetic flavin catalysis plays multiple roles in aerobic oxidative transformations, not only regenerating I2 from in
Photocatalytic direct C–S bond formation: facile access to 3-sulfenylindoles via metal-free C-3 sulfenylation of indoles with thiophenols
作者:Wei Guo、Wen Tan、Mingming Zhao、Kailiang Tao、Lv-Yin Zheng、Yongquan Wu、Deliang Chen、Xiao-Lin Fan
DOI:10.1039/c7ra08086g
日期:——
An efficient and convenient photocatalytic direct C-3 sulfenylation of indoles with thiophenols has been developed for the construction of 3-sulfenylations. This protocol employs thiophenols as the sulfenylating agents, inexpensive rose bengal as the photocatalyst, and shows mild conditions, readily available starting materials, high atom and step atom economy, and environmental advantages. The representative