It is seen that the strong conventional O-H in SI). The π•••π stacking energy for the TSwyn2A(S), which is the major transition state, is -11.6 kcal/mol, whereas the π•••π stacking energy for the minor transition state TSwyn2A'(R) is -9.9 kcal/mol (see Fig. in SI). Therefore, the π•••π interaction is seen to be 1.7 kcal/mol stronger in TSwyn2A(S) than in TSwyn2A'(R) (see Fig. in SI). Adding all the non-covalent interactions for the major TS, i.e. TSwyn2A(S), yields the value -70.0 kcal/mol, while the corresponding value for the minor TS, i.eTSwyn2A'(R), is -63.6 kcal/mol, i.e., unfavourable by 6.4 kcal/mol. This gives us a clear idea as to why one enantioselective product is favoured over the other.For details of the calculations ofthe NCI, please see Section 6in the SI