Gold-catalyzed Michael addition/intramolecular annulation cascade: an effective pathway for the chemoselective- and regioselective synthesis of tetracyclic indole derivatives in water

The report describes a gold(I) complex and trifluoroacetic acid (TFA) cocatalyzed one-pot, Michael addition/intramolecular cyclization cascade reaction for the synthesis of unusual tetracyclic indoles containing a seven-membered ring in water with microwave irradiation (MW). This protocol presents an operationally simple, rapid and environmentally friendly strategy for preparing potential biologically interesting fused-indole molecular architectures from some simple starting materials.