36684-65-8Relevant articles and documents
Tetrahydrocarbazoles by mechanochemical Fischer indolisation
Qiu, Yichen,Puni, Kararaina Te,Duplan, Clotilde C.,Lindsay, Ashley C.,Sperry, Jonathan
supporting information, (2021/05/26)
The Fischer indolisation (FI) typically proceeds in the presence of a Br?nsted or Lewis acid in an organic solvent at elevated temperatures. Herein, we report that tetrahydrocarbazoles (THCs) are accessible by mechanochemical FI at ambient temperature. Using phenylhydrazine hydrochlorides in the presence of silica is critical for this solid-state variant of the FI.
Annulation of Indoles with 1,n-Dibromoalkanes by a Pd(II)-Catalyzed and Norbornene-Mediated Reaction Cascade
Bach, Thorsten,Henkel, Michael
, p. 1231 - 1238 (2020/04/15)
Employing 1,3-dibromopropane, 1,4-dibromobutane, and 1,5-dibromopentane as biselectrophiles, the annulation of indoles was probed in the presence of PdCl 2 (MeCN) 2 as a catalyst and norbornene as a transpositional ligand. Ring formation to a five-membered ring was observed at positions C2 and N, while annulation of a six-membered ring occurred at positions C2 and C3. The latter cascade process was successfully applied to the direct synthesis of 1,2,3,4-tetrahydrocarbazoles from indoles (11 examples, 31-68% yield). Seven-membered-ring annulation was feasible by an initial coupling at positon C2 followed by alkylation at C3.
SBA-15-Pr-SO3H catalyzed one-pot synthesis of indole derivatives via Fischer indole pathway
Ghiyasabadi, Zahra,Bahadorikhalili, Saeed,Saeedi, Mina,Karimi-Niyazagheh, Mona,Mirfazli, Seyedeh Sara
supporting information, p. 606 - 610 (2020/01/03)
In this work, an efficient, user-friendly, and simple procedure was reported for the preparation of indole derivatives catalyzed by the heterogeneous SBA-15-Pr-SO3H via Fischer indole pathway. The title compounds were synthesized from various arylhydrazines and ketones in the presence of 3 mol% of the catalyst in the refluxing ethanol.