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Abstract Non‐covalent chalcogen bond (ChB) interactions have found utility in many fields, including catalysis, organic semiconductors, and crystal engineering. In this study, the transition stabilizing effects of ChB interactions of oxygen and sulfur were experimentally measured using a series of molecular rotors. The rotors were designed to form ChB interactions in their bond rotation transition states. This enabled the kinetic influences to be assessed by monitoring changes in the rotational barriers. Despite forming weaker ChB interactions, the smaller chalcogens were able to stabilize transition states and had measurable kinetic effects on the rotational barriers. Sulfur stabilized the bond rotation transition state by as much as −7.2 kcal/mol without electron‐withdrawing groups. The key was to design a system where the sulfur ‐hole was aligned with the lone pairs of the chalcogen bond acceptor. Oxygen rotors also could form transition state stabilizing ChB interactions but required electron‐withdrawing groups. For both oxygen and sulfur ChB interactions, a strong correlation was observed between transition state stabilizing abilities and electrostatic potential (ESP) of the chalcogen, providing a useful predictive parameter for the rational design of future ChB systems.
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Accelerated reduction and solubilization of elemental sulfur by 1,2-aminothiols
Nucleophilic 1,2-aminothiol compounds readily reduce typically-insoluble elemental sulfur to polysulfides in both water and nonpolar organic solvents. The resulting anionic polysulfide species are stabilized through hydrogen-bonding interactions with the proximal amine moieties. These interactions can facilitate sulfur transfer to alkenes.
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- Award ID(s):
- 2047045
- PAR ID:
- 10317805
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 57
- Issue:
- 93
- ISSN:
- 1359-7345
- 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/D1CC05242J
