Controlling Electronic Events Through Rational Structural Design in Subphthalocyanine-Corrole Dyads: Synthesis,
Víctor Mariñas1,2, Benedikt Platzer3, Jorge Labella2
1Department of Chemical Science and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica, 00133, Rome, Italy.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|July 21, 2022
Summary
Researchers synthesized novel porphyrinoid arrays by covalently linking subphthalocyanine (SubPc) and corrole (Cor) units. These D-A systems exhibit tunable electronic properties, enabling charge separation or energy transfer based on corrole substituents.
Area of Science:
- Supramolecular Chemistry
- Organic Electronics
- Photochemistry
Background:
- Porphyrinoids possess excellent optoelectronic properties and low reorganization energies, making them ideal for donor-acceptor (D-A) systems.
- Developing functional D-A arrays is crucial for advancing organic electronics and photochemistry applications.
Purpose of the Study:
- To synthesize and characterize novel covalently linked subphthalocyanine (SubPc) and corrole (Cor) donor-acceptor systems.
- To investigate the influence of corrole electronic nature on charge transfer and energy transfer processes within these arrays.
- To explore the potential of these tailored porphyrinoid structures for optoelectronic applications.
Main Methods:
- Utilized SubPc axial substitution strategies for efficient synthesis of linked SubPc-Cor molecules.
- Performed in-depth absorption, fluorescence, and electrochemical assays to probe electronic and photophysical properties.
- Employed a qualitative synthetic approach to control and reverse electronic event directionality.
Main Results:
- Successfully synthesized a series of covalently linked SubPc-Cor molecules with controlled short-range linkages.
- Observed distinct photophysical behaviors: charge separation with electron-donating Cor units and quantitative energy transfer from Cor to SubPc with electron-accepting Cor units.
- Demonstrated tunability of electronic events by modifying the electronic nature of the corrole moiety.
Conclusions:
- The covalent linkage of SubPc and Cor units creates versatile D-A systems with tunable photophysical properties.
- The electronic nature of the corrole component dictates the primary photoinduced process (charge separation vs. energy transfer).
- These findings offer a pathway for designing advanced porphyrinoid-based materials for optoelectronic devices.
Related Concept Videos
01:26Photochemical Electrocyclic Reactions: Stereochemistry
1.9K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
1.9K
01:34Woodward–Hoffmann Selection Rules and Microscopic Reversibility
3.3K
Electrocyclic reactions, cycloadditions, and sigmatropic rearrangements are concerted pericyclic reactions that proceed via a cyclic transition state. These reactions are stereospecific and regioselective. The stereochemistry of the products depends on the symmetry characteristics of the interacting orbitals and the reaction conditions. Accordingly, pericyclic reactions are classified as either symmetry-allowed or symmetry-forbidden. Woodward and Hoffmann presented the selection criteria for...
3.3K
01:29The Photochemical Reaction Center
4.2K
Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...
4.2K
01:26Thermal and Photochemical Electrocyclic Reactions: Overview
2.4K
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
2.4K
01:17Thermal Electrocyclic Reactions: Stereochemistry
2.1K
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
2.1K
03:02Colors and Magnetism
12.3K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
12.3K