Synthesis of 3-indole derivatives by copper sulfonato Salen catalyzed three-component reactions in water

Abstract

An efficient three-component reaction of indole, aldehyde, and malononitrile in water catalyzed by a copper(II) sulfonato Salen complex afforded 3-indole derivatives in good to excellent yields up to 97%.

[TBA][Gly] ionic liquid promoted multi-component synthesis of 3-substituted indoles and indolyl-4H-chromenes

“…Multi-component synthesis of 3-substituted indoles and indolyl-4H-chromenes have been achieved using few catalysts such as Zn(salphen) complex, 14 N,N1-dioxide Zn(II) complex, 15 copper (II) sulfonato salen complex, 16 and tetrabutylammonium fluoride. 17 These methods have disadvantages including usage of metal based catalysts, which results either metal contamination in the products or more waste generation from the reaction mixture or usage of organic solvents and toxic reagents with complicated work up procedures.…”

Facile construction of 3-indolochromenes and 3-indoloxanthenes via EDDF catalyzed one-pot three component reactions

“…2,3 Indole is considered as a privileged scaffold for drug discovery, 4,5 as this electron-rich hetero-aromatic fragment is found to possess many important biological functions. Accordingly, various catalysts have been used for the synthesis of 3-indolopyrans including metal salts (FeCl 3 13 and InCl 3 14 ), metal-complexes (Cu(II)sulfonato-salen complex 15 and Zn(salphen) complex 16 ), organo-catalysts (L-proline 17,18 and tetrabutylammonium-fluoride 19 ) and ZnO nanoparticles. 1.…”

Efficient one pot multi-component domino Aldol condensation–Michael addition–Suzuki coupling reaction for the highly functionalized quinolines

“…The parallel reactions are helpful to minimize the cost reasonably and could be done under same reaction conditions (Scheme 1, Eq. 1-5) without isolating the reaction intermediates [7][8][9][10][11][12][13][14][15][16][17][18][19][20] . The expense and mass production conditions of this strategy could be handled through parallel robotized syntheses and by precise investigation of the chemical reactions.…”