2 asymmetric induction strongly depends upon the concentration of the substrate 1. As the concentration of the substrate was lowered a higher degree of enantiomeric excess (ee) was obtained. Using a 2-5 mmol solution is advisable because enantiomerically pure (-)-lactone 2 can be obtained from one recrystallization. Absolute stereochemistry of (-)-butyrolactone 2 was proved to be S by an X-ray crystallographic analysis of the (S)-(-)-a- ...
