Helicity, assembly, and enantiorecognition of chiral AIEgens

International Conference on Stereochemistry

August 18-19, 2016 Sao Paulo, Brazil

Ben Zhong Tang

The Hong Kong University of Science and Technology, China

Posters & Accepted Abstracts: Med chem

Abstract :

As opposed to most fluorophores that suffer from aggregation-caused quenching (ACQ), aggregation-induced emissive luminogens (AIEgens) possess very weak fluorescence in solution, but show strong emission upon aggregation due to restriction of intramolecular motion (RIM). Since AIEgens are often comprised of propeller-shaped structures, i.e. perphenylsiloles or tetraphenylethylene, the attachment of chiral units has recently proven a powerful tool to fabricate chiral AIEgens exhibiting circularly-polarised luminescence (CPL) and for some cases the ability for chiral recognition. Different chiral moieties lead to various assembled structures, such as helical nanoribbons, superhelical ropes, hollow and solid micro-/nanospheres. Generally, these structures exhibit enhaced chiroptical properties when compared to their monomeric counterpart. In this context, we report on a perphenylsilole derivative with side-chains bearing an enantiomerically pure mannose derivative readily assembled into superhelical ropes upon aggregation, which displayed large CPL dissymmetry factors (gem) of �0.32 � a record for purely organic chiral materials. For many biological and pharmaceutical applications, enantiorecognition is one of the most important challenges. Chiral AIEgens that selectively bind to one enantiomer of a chiral compound serve as tool to easily differentiate between two enantiomers. For these kinds of chiral AIEgens, they have great potential to be used in devises that can detect and potentially separate enantiomers; especially chiral drugs, biomolecules, and other chiral molecules of interest.

Biography :

Email: tangbenz@ust.hk