Related Experiment Video
Updated: Jan 9, 2026
09:34
Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
7.9K
Serendipitous Assembly of Chiral Face-Rotating Molecular Boxes Directed by Non-Covalent Templation
Mingyu Cui1, Xue Dong1, Guoqiang Jiang1
1Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM) and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
Organic Letters
|December 5, 2025
Summary
Researchers unexpectedly formed molecular boxes instead of cages using a tetraphenylethene-derived tetraaldehyde and tris(2-aminoethyl)amine. Mandelic acid guided the self-assembly, creating chiral structures with distinct optical activity.
Area of Science:
- Supramolecular Chemistry
- Organic Chemistry
- Materials Science
Background:
- Tetraphenylethene derivatives are known for their aggregation-induced emission properties.
- Imine condensation is a common method for constructing complex molecular architectures.
- Controlling self-assembly pathways is crucial for designing novel supramolecular structures.
Purpose of the Study:
- To investigate the self-assembly of a tetraphenylethene-derived tetraaldehyde with tris(2-aminoethyl)amine.
- To explore the role of mandelic acid in directing the assembly process and inducing chirality.
- To characterize the resulting supramolecular structures and their optical properties.
Main Methods:
- Mandelic acid-mediated imine condensation reaction.
- Nuclear Magnetic Resonance (NMR) spectroscopy for structural elucidation.
- Electronic Circular Dichroism (ECD) spectroscopy for assessing chirality.
- X-ray crystallography for definitive structural determination.
Main Results:
- Unexpected formation of [2 + 4] face-rotating molecular boxes, deviating from the anticipated [6 + 8] cubic cages.
- The synthesized assemblies exhibit D2 symmetry and possess homochiral tetraphenylethene facial units.
- Mandelic acid acts as a chiral auxiliary, influencing assembly via hydrogen bonding, steric effects, and C-H···π interactions.
- NMR, ECD, and X-ray analyses confirmed the formation of diastereomeric supramolecular complexes with unique optical activity.
Conclusions:
- The study demonstrates a serendipitous pathway to novel [2 + 4] molecular boxes.
- Mandelic acid effectively steers supramolecular assembly and induces chirality in the resulting structures.
- The diastereomeric complexes exhibit distinct chiroptical properties, highlighting the potential for designing chiral materials.
Related Concept Videos
02:05Prochirality
4.8K
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
4.8K
02:25Molecules with Multiple Chiral Centers
14.7K
Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...
14.7K
02:30Chirality in Nature
16.5K
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid.
16.5K
02:18Fischer Projections
16.1K
Learning to draw Fischer projections of molecules and understanding their relevance plays a crucial role in the visual depiction of organic molecules. A Fischer projection is a two-dimensional projection on a planar surface to simplify the three-dimensional wedge–dash representation of molecules. This is especially helpful in the case of molecules with multiple chiral centers that can be difficult to draw. Here, all the bonds of interest are represented as horizontal or vertical lines. While...
16.1K
02:30Chirality at Nitrogen, Phosphorus, and Sulfur
6.8K
Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
6.8K
02:25Chirality
28.9K
Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
28.9K