Friedel–crafts-type alkylation of indoles in water using amphiphilic resin-supported 1,10-phenanthroline–palladium complex under aerobic conditions

Abstract

The palladium-catalyzed Friedel-Crafts-type alkylation of indoles in water has been achieved using amphiphilic polystyrene-poly(ethylene glycol) (PS-PEG) resin-supported phenanthroline-palladium complexes in water under aerobic conditions, affording the corresponding products with good-to-high yield. The polymeric catalyst was also found to promote the C3-alkylation reaction to give a thermodynamic alkylation product with high selectivity. The polymeric catalyst was recovered and reused several times without any loss of catalytic activity.