Fig. 6: Mechanism studies.
From: Bis-indole chiral architectures for asymmetric catalysis
A Results of performing reactions with intermediates 2a and/or 3a under optimal conditions. B Positive cross over demonstrates reversibility. C Monitoring the concentration of 2a, 3a and 4a over time. D Experiment reads out primary kinetic isotope effect. E Evaluating SPINDOLE 4a catalytic reactivity. F Proposed stereochemical model for explaining the selectivity determined at the deprotonation step. G Proposed mechanism on the basis of evidence presented in A-F.
