Self-sorting chiral organogels from a long chain carbamate of 1-benzyl-pyrrolidine-3,4-diol

Abstract

(3S,4S)-1-benzylpyrrolidine-3,4-diyl bis(dodecylcarbamate), a pyrrolidine ring bearing two long carbon chains connected by carbamate functionalities, is the origin of stable gels in both polar and apolar solvents. Several experimental and theoretical techniques (cryo-TEM, AFM, DSC, circular dichroism (CD), molecular mechanics calculations and CD simulations) were used to describe the formation and the characteristics of the chiral supramolecular structures and fibers constituting the gel. The chirality at both supramolecular and microscopic level depends on the configuration of the stereogenic centers of the pyrrolidine unit. The gels formed by the two enantiomers of the gelator and their mixtures display enantiomeric discrimination resulting in a self-sorting process. In fact, separate fibers of opposite helicity are obtained, which suggests this class of compounds has strong potential for realizing functionalized chiral architectures.