A Bifunctional Coordination‐Chain‐Based Hydrogen‐Bonded Framework for Quantitative Enantioselective Sensing

Abstract

Enantioselective sensing is highly crucial and challenging due to the highly similar physical/chemical properties of enantiomers which may have different chemical impact on organism. Luminescent coordination compounds have attracted great attention as sensing materials based on their controllable chemical and electric structures that can be highly matched with the targeted species. To achieve high‐performance enantioselective sensing, the direct synthesis of chiral and luminescent bifunctional coordination compounds is a rational way but highly challenging due to the price and synthesis difficulty. Herein, an anionic coordination‐chain‐based hydrogen‐bonded framework was applied as a host to accommodate chiral and luminescent centers via a facile cation exchange reaction, affording a bifunctional framework that possesses enantioselective sensing properties for the mixture of enantiomers. This study paves a pathway for constructing multifunctional coordination chain‐based hydrogen‐bonded frameworks for rapidly enantioselective sensing function.

Postsynthetic Modification of Hydrogen‐Bonded Frameworks

“…Recently, the chiral cation L-carnitine was introduced into the pores of NKU-1000 with the second luminescence center of Tb 3 + ion, to generate a bifunctional NKU-1000-CÀ Tb (Figure 5). [38] For electrochemical energy storage application, Li + ions were introduced into the ionic NKU-1000 through guest exchange, to form Li@NKU-1000. [39] Thirdly, the hydrogen-bonded frameworks provide a means to modify the connection modes by inserting metal ions between the building blocks with specific donors to form coordination bonds, resulting in the transformation to coordination compounds.…”

“…[39] For the chiral properties, we developed a strategy that introducing chiral cations into an anionic hydrogen-bonded framework through the exchange of the cations inside the pores (Figure 5). [38] The post-synthetically modified NKU-1000-C performs similar Cotton effects with the chiral cation, and can be applied as the enantioselective sensor for small chiral organic molecules, such as potent intermediates for pharmaceuticals and industries, 2-amino-1-propanol and 1,2-propanediol (Figure 11). Detailed sensing mechanism studies revealed that the competitive absorption and Förster resonance energy transfer processes contribute cooperatively to the emission intensity changes, while the post-synthetically modified chiral cations that selectively interact with targeting chiral molecules induces the enantioselective recognition property.…”

“…Detailed sensing mechanism studies revealed that the competitive absorption and Förster resonance energy transfer processes contribute cooperatively to the emission intensity changes, while the post-synthetically modified chiral cations that selectively interact with targeting chiral molecules induces the enantioselective recognition property. [38] The diverse array of postsynthetic modification methods available has empowered the deliberate alteration of properties, including mechanical characteristics, luminescence, electrochemistry, and chirality, within hydrogen-bonded frameworks to be applied for specific applications. This expanded versatility has substantially broadened the potential applications of hydrogen-bonded frameworks.…”

In situ generated dimethylamine constructs a robust hydrogen-bonded organic framework for selective fluorescence detection

“…1 HOFs represent a class of crystalline framework structures formed by intermolecular hydrogen bonds between organic or metal-containing molecules, assembled through the synergistic action of other non-covalent interactions such as π–π stacking. 2 Current research efforts focus on these aspects, propelling advancements in various fields including dye adsorption and degradation, 3,4 proton conduction, 5,6 catalysis, 7,8 luminescence phenomena, 9,10 anti-counterfeiting and sensing technologies, 11–16 biological applications, 17–20 gas separation processes, 21,22 enantiomer resolution and separation of aromatic compounds, 23 etc. Since the beginning of the 21st century, MOFs have experienced explosive development, while COFs have recently entered a stage of rapid growth.…”

Enhancing enantioselectivity in chiral metal organic framework fluorescent sensors

“…9 Despite the large potential for the development of MOFs as fluorescent chiral sensors, only a handful of studies have been reported. 5,9–18 A challenge facing MOF-based fluorescent chiral sensors is engendering a high degree of enantioselectivity in interactions with enantiomeric pairs.…”