Regiocontrolled direct C4 and C2-methyl thiolation of indoles under rhodium-catalyzed mild conditions
作者:Saurabh Maity、Ujjwal Karmakar、Rajarshi Samanta
DOI:10.1039/c7cc07086a
日期:——
Rh(III)catalyzed general strategy was developed for the site selective remote C4 (sp2) and C2 (sp3)-methyl thiolation of indole core keeping the oxime directing group at the C3 position. The transformation was accomplished undermildconditions with wide scope and functional group tolerance. The directing group can easily be removed after operation. Methyl substitution at the C2 position of indole core
Rhodium(III)-Catalyzed Regioselective Direct C4-Alkylation and C2-Annulation of Indoles: Straightforward Access to Indolopyridone
作者:Aniruddha Biswas、Rajarshi Samanta
DOI:10.1002/ejoc.201701755
日期:2018.3.29
C4‐alkylation and C2‐annulation of indole derivative has been developed by using variable diazo esters. Fine tuning of the reactivity of diazo esters leads to control in regioselectivity with wide scope and functional‐group tolerance. A straightforward approach has been established to furnish an indolopyridone scaffold.
A radical addition and cyclization relay promoted by Mn(OAc)3⋅2H2O: Synthesis of 1,2-oxaphospholoindoles and mechanistic study
作者:Meng-Meng Xu、Lu-Yao Kou、Xiao-Guang Bao、Xiao-Ping Xu、Shun-Jun Ji
DOI:10.1016/j.cclet.2021.02.001
日期:2021.6
Novel and efficient Mn(OAc)3⋅2H2O promoted radical addition-[4 + 1] cyclization relay of 3-indolymethanols and phosphites was disclosed, which afforded 1,2-oxaphospholoindole derivatives in moderate to good yields. Based on the experimental and computational studies, a mechanism involving radical addition and intramolecular cyclization cascade was proposed.
[reaction--see text] Indoles are selectively acylated at the 3-position in high yields on treatment with a wide variety of acyl chlorides in CH(2)Cl(2) in the presence of diethylaluminum chloride or dimethylaluminum chloride. The reaction proceeds under mild conditions and is applicable to indoles bearing various functional groups without NH protection.
A weak carbonyl coordination-guided regioselective C4 allylation of indoles is demonstrated using the versatile Morita-Baylis-Hillman adduct in the presence of Rh catalysts in a redox-neutral fashion. The substrate scope, functional group diversity, oxidant free character, mechanistic aspects, and synthetic utilities are important practical features.