With these modified derivatives, high stereocontrol of up to 98% ee could be achieved in a model Mukaiyama aldol reaction for a range of different substrates.
Importantly, the crucial role of halogen bonding in this catalytic process was demonstrated by the low performance of the non-iodinated variants and by DFT calculations.
The latter also indicate that the stereoinduction is based on the imposed orientation of the substrates towards each other.
The detailed description can be found in the international edition of the journal 'Angewandte Chemie'.