Absolute Configuration Control in Covalent Organic Frameworks
Huimin Ding1, Ya Zhang1,2, Zixing Wang3
1College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
Journal of the American Chemical Society
|August 4, 2025
Summary
This study demonstrates how the absolute configuration of chiral precursors precisely controls the structure and function of covalent organic frameworks (COFs). Specific precursor pairings dictate whether COFs exhibit chiral quartz topology for racemate resolution or achiral diamondoid topology.
Area of Science:
- Materials Science
- Organic Chemistry
- Crystallography
Background:
- Chiral building blocks are key in reticular materials, but their absolute configuration's impact on framework properties is unclear.
- Understanding stereochemical control is crucial for designing advanced functional materials.
Purpose of the Study:
- To investigate how the absolute configuration of chiral precursors influences the synthesis and properties of covalent organic frameworks (COFs).
- To achieve stereoselective synthesis of isomeric 3D COFs with predictable topologies and functions.
Main Methods:
- Stereoselective synthesis using axially chiral binaphthalene-functionalized precursors with defined stereochemistry.
- Characterization of four ultrastable, highly crystalline isomeric 3D COFs.
- Evaluation of the chiral separation capabilities of the synthesized COFs.
Main Results:
- Four isomeric 3D COFs were synthesized, with two exhibiting enantiomeric chiral quartz (qtz) topology and two showing achiral diamondoid (dia) topology, solely based on precursor absolute configuration.
- The qtz COFs demonstrated effective resolution of racemates, while the dia COFs lacked chiral separation ability.
- Structural differences, including framework chirality and pore environment, correlated with observed functional divergence.
Conclusions:
- Absolute configuration is a critical determinant of framework chirality, topology, and ultimately, function in reticular materials.
- This work provides direct experimental evidence for stereochemical control in COF synthesis.
- Offers new strategies for designing chiral reticular materials with tailored separation properties.
Related Concept Videos
01:18Aromatic Hydrocarbon Anions: Structural Overview
2.9K
Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
Due to the absence of continuous...
Due to the absence of continuous...
2.9K
02:11Conformations of Cyclohexane
13.1K
Cyclohexane does not exist in a planar form due to the high angle and torsional strain it would experience in the planar structure. Instead, it adopts non-planar chair and boat conformations.
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal...
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal...
13.1K
02:02Chair Conformation of Cyclohexane
15.2K
The chair conformation is the most stable form of cyclohexane due to the absence of angle and torsional strain. The absence of angle strain is a result of cyclohexane’s bond angle being very close to the ideal tetrahedral bond angle of 109.5° in its chair conformer. Similarly, the torsional strain is also absent owing to the perfectly staggered arrangement of bonds.
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this...
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this...
15.2K
02:40MO Theory and Covalent Bonding
11.3K
The molecular orbital theory describes the distribution of electrons in molecules in a manner similar to the distribution of electrons in atomic orbitals. The region of space in which a valence electron in a molecule is likely to be found is called a molecular orbital. Mathematically, the linear combination of atomic orbitals (LCAO) generates molecular orbitals. Combinations of in-phase atomic orbital wave functions result in regions with a high probability of electron density, while...
11.3K
01:18Aromatic Hydrocarbon Cations: Structural Overview
3.0K
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group...
Removing one hydrogen from the intervening CH2 group...
3.0K
02:58Crystal Field Theory - Octahedral Complexes
27.9K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
27.9K