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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
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Torquoselectivity in Cyclobutene Ring Openings and the Interatomic Interactions That Control Them.
1Instituto de Química, Universidad Nacional Autónoma de México , Circuito exterior, Ciudad Universitaria Coyoacán, México, D.F., México 04510.
The Journal of Physical Chemistry. A
|October 11, 2016
Summary
Torquoselectivity in ring openings is governed by interactions between cyclobutene
Area of Science:
- Computational Chemistry
- Organic Chemistry
- Quantum Chemistry
Background:
- Torquoselectivity explains diastereomeric preferences in electrocyclic ring openings.
- Understanding atomic interactions is key to controlling reaction outcomes.
Purpose of the Study:
- To investigate the atomic interactions driving torquoselectivity in 3-substituted cyclobutenes.
- To quantitatively and qualitatively evaluate these interactions using advanced computational methods.
Main Methods:
- Employed the Quantum Theory of Atoms in Molecules (QTAIM).
- Utilized the Electron Localizability Indicator (ELI-D) for topological analysis.
- Applied the Interacting Quantum Atoms (IQA) energy partition method.
Main Results:
- The interaction between cyclobutene's C4 and the C3 substituent (R5) in the transition state dictates torquoselectivity.
- A strong interaction in 3-borylcyclobutene leads to a proto-covalent bond between B5 and C4.
- A surprising correlation exists between bond critical point density, bond path shape, activation energies, and torquoselectivity, despite the absence of a direct bond path between C4 and R5.
Conclusions:
- The C4-R5 interaction is the primary driver of torquoselectivity in these systems.
- Computational methods reveal subtle yet significant atomic interactions influencing reaction pathways.
- Electron density topology at bond critical points correlates with observed reactivity and stereochemical outcomes.
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