p-sulfonic acid calix[4]arene: An efficient reusable organocatalyst for the synthesis of bis(indolyl)methanes derivatives in water and under solvent-free conditions
β-cyclodextrin hydrate has been investigated towards the eco-compatible synthesis of bis-(indolyl)methanes in aqueous medium by the chemoselective reaction of indoles with differently substituted aryl and alkyl aldehydes under mild reaction conditions. The catalytic attributes of β-cyclodextrin hydrate were also demonstrated through molecular docking and DFT studies. Reactions were slower in D2O than in H2O
p-sulfonic acid calix[4]arene: An efficient reusable organocatalyst for the synthesis of bis(indolyl)methanes derivatives in water and under solvent-free conditions
Résumé In this work, a green, simple and highly efficient procedure for the synthesis of bis(indolyl)methanes is described. The condensation of indoles catalyzed by p-sulfonic acid calix[4]arene in water and under solvent-free conditions afford the title compounds in high yields and relatively short reaction times.
The photochemicalreaction of an aromatic aldehyde with indole or 2-methylindole gave 3,3′-diindolylmethanes in ca. 50% yield. A mechanism involving a electron transfer process is proposed.
Friedel–Crafts Alkylation of Indoles with Aldehydes/Ketones Catalyzed by Bromodiarylethene-Based Photoacid Generators
作者:Valerii Z. Shirinian、Alexey V. Zakharov、Sofia M. Timofeeva
DOI:10.1055/a-2270-3973
日期:——
Diarylethenes (DAEs) with a bromine atom at the ring-closing position catalyze C–C bonding reactions induced by UV or sunlight. Upon photo-irradiation, bromodiarylethenes undergo 6π-electrocyclization (6π-EC), followed by the release of an acid species that catalyzes the double Friedel–Crafts addition of indoles to aldehydes and isatins to form the corresponding triarylmethanes and 3,3′-diarylindolin-2-ones