Synthesis of Heteroarylogous 1H-Indole-3-carboxamidines via a Three-Component Interrupted Ugi Reaction
摘要:
A novel one-pot multicomponent synthesis of heteroarylogous 1H-indole-3-carboxamidines starting from readily available N-alkyl-N-(1H-indol-2-ylmethyl) amines, isocyanides, and carbonyl compounds is reported. The strategy exploits the ability of the indole nucleus to interrupt the classical Ugi reaction, by intercepting the nascent nitrilium ion.
Synthesis of Heteroarylogous 1H-Indole-3-carboxamidines via a Three-Component Interrupted Ugi Reaction
摘要:
A novel one-pot multicomponent synthesis of heteroarylogous 1H-indole-3-carboxamidines starting from readily available N-alkyl-N-(1H-indol-2-ylmethyl) amines, isocyanides, and carbonyl compounds is reported. The strategy exploits the ability of the indole nucleus to interrupt the classical Ugi reaction, by intercepting the nascent nitrilium ion.
Herein we disclose an efficient and flexible approach to biologically relevant 3,4-dihydropyrazino[1,2-alpha] indol-1(2H)ones and 3,4-dihydropyrrolo[1,2-alpha]pyrazin-1(2H)ones through a domino Michael/intra-molecular nucleophilic substitution pathway using potassium hydroxide in dichloromethane. Variously substituted vinyl selenones and 1H-indole-2-carboxamides or 1H-pyrrole-2-carboxamides have been employed with success in chemo and regio-selective processes. The introduction of an amino acid portion on the amidic function is well tolerated without racemization. (C) 2018 Elsevier Ltd. All rights reserved.