869206-30-4Relevant academic research and scientific papers
Autoamplification of molecular chirality through the induction of supramolecular chirality
Vandijken, Derk Jan,Beierle, John M.,Stuart, Marc C. A.,Szymanski, Wiktor,Browne, Wesley R.,Feringa, Ben L.
, p. 5073 - 5077 (2014/05/20)
The novel concept for the autoamplification of molecular chirality, wherein the amplification proceeds through the induction of supramolecular chirality, is presented. A solution of prochiral, ring-open diarylethenes is doped with a small amount of their chiral, ring-closed counterpart. The molecules co-assemble into helical fibers through hydrogen bonding and the handedness of the fibers is biased by the chiral, ring-closed diarylethene. Photochemical ring closure of the open diarylethene yields the ring-closed product, which is enriched in the template enantiomer. There and back again: Doping a mixture of rapidly interconverting prochiral, open diarylethenes (left) with their enantiopure, closed counterparts, led to formation of gel fibers of preferred helicity (center). This supramolecular chirality was transferred to the molecular level by photochemical ring closing, thus yielding a chiral product (right) which is enriched in the enantiomer originally used as a template.
Dynamic chirality, chirality transfer and aggregation behaviour of dithienylethene switches
de Jong, Jaap J.D.,van Rijn, Patrick,Tiemersma-Wegeman, Theodora D.,Lucas, Linda N.,Browne, Wesley R.,Kellogg, Richard M.,Uchida, Kingo,van Esch, Jan H.,Feringa, Ben L.
, p. 8324 - 8335 (2008/12/21)
The synthesis and characterisation of a series of chiral and achiral low molecular weight organogelators (LMWGs) based on bis-amide substituted dithienylethene photochromic switches is reported. The LMWGs gelate a range of solvents depending on the specific functionalisation of the hydrogen bonding amide groups. In mixtures of chiral and achiral LMWGs the stereochemical outcome of the chiral aggregation is determined by the chiral LMWG molecules in most cases. However, for the first time we demonstrate that the stereochemical outcome of the aggregation can be influenced by the achiral LWMG molecules in some cases. Furthermore specific π-π (and/or van der Waals) interactions of chiral LMWGs 1-3o with the solvent allow the solvent to influence the control of chirality of aggregation. This influence of the solvent has a dramatic effect on whether four- or two-gel states are available.
