Enantioselective Complexation of Chiral Oxirane Derivatives by an Enantiopure Cryptophane in Water

Nicolas de Rycke (1) , Marion Jean (2) , Nicolas Vanthuyne (2) , Thierry Buffeteau (3) , T. Brotin (1)

1 LC - Laboratoire de Chimie - UMR5182
2 ISM2 - Institut des Sciences Moléculaires de Marseille
3 ISM - Institut des Sciences Moléculaires

We show here that optically active cryptophane 1 bearing phenol functions can efficiently bind the two enantiomers of 2‐(chloromethyl)oxirane, ethyloxirane, and 2,2′‐bioxirane derivatives in aqueous solution. The binding process is characterized by high‐field 1H NMR signals that are specific to the encapsulated species. In all cases, an enantioselective effect was observed and a relationship between the molecular volume of the guest and the binding constant can be established, even though the flexibility of the guest molecule also seems to play a role. In this series, the 2,2′‐bioxirane guest is a particularly interesting example, because this compound possesses two stereogenic centers. Thus, in solution, three different pairs of enantiomers can be obtained in the presence of the optically active host 1. Electronic circular dichroism (ECD) spectroscopy has also been used to characterize these complexes; specific ECD spectra recorded in the 1Lb region were obtained for each diastereomer.

Domaines: Chimie organique

Nicolas de Rycke, Marion Jean, Nicolas Vanthuyne, Thierry Buffeteau, T. Brotin. Enantioselective Complexation of Chiral Oxirane Derivatives by an Enantiopure Cryptophane in Water. European Journal of Organic Chemistry, 2018, 2018 (13), pp.1601-1607. ⟨10.1002/ejoc.201800142⟩. ⟨hal-01955471⟩