61675-19-2Relevant articles and documents
Recyclable and reusablen-Bu4NBF4/PEG-400/H2O system for electrochemical C-3 formylation of indoles with Me3N as a carbonyl source
Cheng, Didi,Li, Jingyi,Li, Yujin,Ling, Fei,Liu, Lei,Liu, Tao,Zhong, Weihui
supporting information, p. 4107 - 4113 (2021/06/17)
A safe, practical and eco-friendly electrochemical methodology for the synthesis of 3-formylated indoles has been developed by the utilization of Me3N as a novel formylating reagent. Stoichiometric oxidants, metal catalysts, and activating agents were avoided in this method, and an aqueous biphasic system ofn-Bu4NBF4/PEG-400/H2O was used as a recyclable and reusable reaction medium, which made this electrosynthesis approach more sustainable and environmentally friendly. This process expanded the substrate scope and functional group tolerance for bothN-EDG andN-EWG indoles. Furthermore, late-stage functionalization and total/formal synthesis of drugs and natural products were realized by means of this route.
Metal-Free Dearomatization: Direct Access to Spiroindol(en)ines in Batch and Continuous-Flow
Ranjan, Prabhat,Ojeda, Gerardo M.,Sharma, Upendra K.,Van der Eycken, Erik V.
supporting information, p. 2442 - 2446 (2019/01/29)
A metal-free, phosphine-catalyzed intramolecular “umpolung Michael addition” on alkynes to form spiroindol(en)ines is reported. This nucleophilic catalysis enables the formation of a wide scope of five- and six-membered spiroindol(en)ines in moderate to excellent yields in batch as well as under continuous-flow conditions. Triphenylphosphine-catalyzed nucleophilic activation of alkynes allows the exclusive formation of exo-product under mild reaction conditions.
Revision of the Structure and Total Synthesis of Topsentin C
Golantsov, Nikita E.,Festa, Alexey A.,Varlamov, Alexey V.,Voskressensky, Leonid G.
, p. 2562 - 2562 (2017/05/22)
An efficient synthetic approach to access (indol-3-yl)ethane-1,2-diamines with a protecting group at the indole N atom from readily available 3-(2-nitrovinyl)indoles is reported. This approach includes solvent-free conjugate addition of O-pivaloylhydroxylamines to 1-Boc-3-(2-nitrovinyl)indoles followed by mild reduction of the adducts. The obtained (indol-3-yl)ethane-1,2-diamines are convenient synthetic precursors for several classes of marine alkaloids. The first total synthesis of racemic topsentin C, a secondary metabolite from Hexadella sp., based on this approach is reported. The initially proposed structure for topsentin C has been revised.