Cyclizations of unsymmetrical bis-1,2-(3-indolyl)ethanes: Synthesis of (-)-tjipanazole F1

Article abstract of DOI:10.1016/S0040-4020(97)01036-3

The inter- and intramolecular dimerization of 3-substituted indoles was studied. The rate and extent of dimerization depends on the indole substituents. The intramolecular dimerization of unsymmetrical bis-1,2-(3-indolyl)ethanes could be controlled using either thermodynamic reaction conditions (neat trifluoroacetic acid) or kinetic conditions (2 equiv acid/chloroform). This control of regiochemistry has been applied to an efficient synthesis of (-)- tjipanazole F1.