Chiral synthetic hosts for efficient enantioselective molecular recognition. Design principles and synthetic aspects.

Discrimination of enantiomeric substrate molecules is one of the fundamental properties of biological hosts. Replicating enantioselective molecular recognition with synthetic receptors is a topic of interest with implications in diverse applications such as bioinspired enantioselective catalysis, enantiomer separation, or sensing. In this review, five different systems reported in the literature are discussed, and their performance and versatility are analyzed. A recently reported host featuring a flexible scaffold challenges the long-established view that a high degree of preorganization in combination with strongly directional non-covalent interactions is required for efficient enantiodiscrimination. The review is complemented with an analysis of the synthetic effort required for each of the hosts presented.