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Abstract The interaction between two square palladium (II) dianions PdX42−(X=Cl, Br) is evaluated by crystal study and analyzed by quantum chemical means. The arrangement within the crystal between each pair of PdX42−neighbors is suggestive of a Pd⋅⋅⋅X noncovalent bond, which is verified by a battery of computational protocols. While the potential between these two bare dianions is computed to be highly repulsive, the introduction of even just two counterions makes this interaction attractive, as does the presence of a constellation of point charges. It is concluded that there is indeed a stabilizing Pd⋅⋅⋅X bond, but it is incapable of overcoming the strong coulombic repulsive force between two dianions. While the QTAIM, NBO, and NCI tools can indicate the presence of a noncovalent bond, they are unable to distinguish an attractive from a repulsive interaction.
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The role of attractive dispersion interaction in promoting the catalytic activity of asymmetric hydrogenation
This study proves Wanbin Zhang's finding that weak attractive interactions between substrate and ligand play an important role in metal-catalyzed asymmetric hydrogenations and shows that the dispersion interaction is the major attractive interaction.
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- Award ID(s):
- 2153972
- PAR ID:
- 10505403
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Organic Chemistry Frontiers
- Volume:
- 10
- Issue:
- 14
- ISSN:
- 2052-4129
- Page Range / eLocation ID:
- 3485 to 3490
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D3QO00332A
