Three-dimensional covalent organic frameworks based on a π-conjugated tetrahedral node
Miaomiao Wu1, Zhen Shan1, Jinjian Wang1
1School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, China. zhanggen@njust.edu.cn.
Chemical Communications (Cambridge, England)
|September 20, 2021
Summary
Researchers developed fully conjugated 3D covalent organic frameworks (COFs) using a novel π-conjugated node. This breakthrough advances the synthesis of complex 3D COFs for diverse applications.
Area of Science:
- Materials Science
- Organic Chemistry
- Nanotechnology
Background:
- Constructing three-dimensional (3D) covalent organic frameworks (COFs), particularly those with full π-conjugation, presents significant synthetic challenges.
- Existing methods often struggle to achieve the desired dimensionality and electronic properties in COFs.
Purpose of the Study:
- To report a novel method for synthesizing fully conjugated 3D covalent organic frameworks (COFs).
- To introduce a new tetrahedral node for building complex 3D COF architectures.
Main Methods:
- Utilized a saddle-like, π-conjugated cyclooctatetrathiophene (COTh) as a tetrahedral building block.
- Employed established synthetic strategies for COF construction, adapted for the novel node.
Main Results:
- Successfully synthesized fully conjugated 3D covalent organic frameworks (COFs) using the COTh node.
- Demonstrated the versatility of the COTh node in creating structurally diverse 3D COFs.
Conclusions:
- The developed method overcomes previous limitations in 3D COF construction.
- The new 3D COFs exhibit rich structural diversity and hold promise for various potential applications.
Related Concept Videos
01:24π Molecular Orbitals of 1,3-Butadiene
10.3K
Conjugated dienes have lower heats of hydrogenation than cumulated and isolated dienes, making them more stable. The enhanced stabilization of conjugated systems can be understood from their π molecular orbitals.
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the number...
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the number...
10.3K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
45.4K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
45.4K
02:40MO Theory and Covalent Bonding
12.4K
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...
12.4K
02:42Valence Bond Theory
9.8K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
9.8K
01:18π Molecular Orbitals of the Allyl Cation and Anion
4.8K
An allyl group is a three-carbon conjugated system where the sp³-hybridized allylic carbon is bonded to a CH=CH2 group via a single bond. Allyl anions can be obtained by treating propene with a strong base that can deprotonate methyl groups. Allyl cations are formed as intermediates during substitution reactions involving allylic halides. In both cases, the hybridization of the allylic carbon changes from sp3 to sp2, giving rise to a carbon chain with three sp2-hybridized carbons, each with...
4.8K
01:13Five-Membered Heterocyclic Aromatic Compounds: Overview
4.5K
Heterocyclic aromatic compounds are cyclic compounds that are aromatic and have one or more heteroatoms—atoms other than carbon, in the ring. Depending upon the number of atoms present in the ring, they can be either five or six-membered. Examples of five-membered heterocyclic aromatic compounds include pyrrole, furan, thiophene, and imidazole. Pyrrole consists of one nitrogen atom having one lone pair of electrons. Furan and thiophene have one oxygen and one sulfur heteroatom,...
4.5K