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Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
A chiral meso-ABC-corrolatochromium(V) complex
Olga A Egorova1, Olga G Tsay, Snehadrinarayan Khatua
1Molecular Logic Gate Laboratory, Department of Chemistry, and School of Molecular Science (BK 21), Korea Advanced Institute of Science and Technology (KAIST), 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea.
Inorganic Chemistry
|April 18, 2009
Summary
Researchers synthesized the first chiral ABC-metallocorrole complex with varying electron-withdrawing groups. This chromium(V) complex, oxo[5-(4-bromophenyl)-10-(pentafluorophenyl)-15-(2-thianaphthyl)corrolato]chromium(V) (7), was characterized by X-ray crystallography and spectroscopy.
Area of Science:
- Coordination Chemistry
- Organometallic Chemistry
- Materials Science
Background:
- Metallocorrole complexes are macrocyclic compounds with diverse applications.
- Chiral metallocorroles are less explored, limiting their potential in asymmetric synthesis and catalysis.
- The synthesis of metallocorroles with varied meso-substituents presents challenges in controlling electronic properties.
Purpose of the Study:
- To synthesize and characterize the first chiral ABC-metallocorrole complex.
- To investigate the structural and electronic properties of a chromium(V) metallocorrole with differentially substituted meso-positions.
- To compare the properties of the new complex with a related A(3)-substituted analogue.
Main Methods:
- Adaptation of a multistep synthesis protocol for metallocorrole preparation.
- Aerobic oxidation using chromium hexacarbonyl (Cr(CO)6) for complex formation.
- Characterization using X-ray crystallography, electron paramagnetic resonance (EPR) spectroscopy, and cyclic voltammetry.
Main Results:
- Successful synthesis of oxo[5-(4-bromophenyl)-10-(pentafluorophenyl)-15-(2-thianaphthyl)corrolato]chromium(V) (7), the first chiral ABC-metallocorrole.
- X-ray crystal structure confirmed the presence of two enantiomers and the specific arrangement of meso-substituents.
- EPR spectroscopy (g(iso) = 1.99) and cyclic voltammetry provided data comparable to the A(3)-substituted analogue, [tris(pfp)cCr(V)O].
Conclusions:
- The study reports the first chiral ABC-metallocorrole, expanding the scope of metallocorrole chemistry.
- The differential electronic nature of the meso-substituents in complex 7 influences its properties.
- The characterized complex serves as a valuable platform for further studies in catalysis and materials science.
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