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Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
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Electronically Excited States of Borylenes
Małgorzata Krasowska1, Marc Edelmann1, Holger F Bettinger1
1Institut für Organische Chemie, Universität Tübingen , Auf der Morgenstelle 18, 72076 Tübingen, Germany.
The Journal of Physical Chemistry. A
|August 6, 2016
Summary
This study computationally investigates borylene excited states, revealing n → π* electronic transitions. These findings aid in identifying these elusive reactive intermediates using spectroscopy.
Area of Science:
- Computational Chemistry
- Spectroscopy
- Quantum Chemistry
Background:
- Borylenes (RB) are reactive intermediates with poorly understood excited states.
- Existing spectroscopic data is limited to diatomic borylenes.
Purpose of the Study:
- To computationally explore the electronic structure and geometry of diverse substituted borylenes.
- To investigate the impact of substituents on borylene electronic properties and excitation energies.
Main Methods:
- Density Functional Theory (DFT) calculations (B3LYP/def2-TZVP) for geometry optimization.
- Equation of Motion Coupled-Cluster (EOM-CCSD) and Time-Dependent DFT (TD-DFT) for excitation energy calculations.
- Analysis of frontier molecular orbitals, HOMO-LUMO gaps, and singlet-triplet energy splittings.
Main Results:
- Optimized geometries for singlet and triplet states of various borylenes.
- Computed excitation energies and identified n → π* electronic transitions.
- Substituent effects on electronic properties and transition characteristics were quantified.
Conclusions:
- The study provides detailed electronic structure insights into substituted borylenes.
- Identified electronic transitions can guide experimental spectroscopic identification.
- Computational data serves as a valuable reference for future borylene research.
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