Selecting the optimized conditions of Table , entry 2, the concomitant HS/HA reaction was performed on an approximatively 1 mmol scale yielding (R,S)-APnol in 51% isolated yield, 96% ee and a dr of 3.6:1. Engaging (R)-BTA instead of (S)-BTA in the catalytic mixture leads to (S,R)-APnol with similar yield and selectivity (entries 5 and 6) as expected for homochiral BTA helical catalysts adopting opposite screw-sense preferences.