A New, Simple, and High-Yielding Synthesis of 2,9-Dihydro-1H-pyrido[3,4-b]indol-1-ones
摘要:
A new, simple, and high-yielding method was developed to prepare 2,9-dihydro-1H-pyrido[3,4-b]indol-1-ones by selective cyclization of the appropriate N-(2,2-dimethoxyethyl)-1H-indole-2-carboxamide in polyphosphoric acid at 110 degrees C for 30 minutes. The reaction yield was strongly dependent on the acid used. The method was less affected by the presence of electron-donating and -withdrawing substituents at 5-position of the indole nucleus.
Microwave-assisted acid-catalyzed nucleophilic heteroaromatic substitution: the synthesis of 7-amino-6-azaindoles
作者:Maxim A. Nechayev、Nikolay Yu. Gorobets、Svetlana V. Shishkina、Oleg V. Shishkin、Sergiy M. Kovalenko
DOI:10.1016/j.tet.2014.12.057
日期:2015.2
Derivatives of 7-amino-6-azaindole containing variable substituent in the amino group were synthesized via acid-catalyzed nucleophilicheteroaromaticsubstitution (SNHetarH+) using 7-chloro-6-azaindoles as substrates and aliphatic and aromatic amines as nucleophiles. The protonation of the pyridine nitrogen in the starting 7-chloro-6-azaindoles is presumed to be the key stage of the reaction mechanism