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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Amine superbases stabilized by extended hydrogen bond networks.
1Department of Chemistry, Trinity University , 1 Trinity Place, San Antonio, Texas 78212, United States.
The Journal of Organic Chemistry
|October 8, 2013
Summary
Researchers explored extended hydrogen-bonding networks to create superbases. This study found new superbases with proton affinities significantly higher than existing ones, particularly decalin base 25 and adamantane base 31.
Area of Science:
- Organic Chemistry
- Computational Chemistry
- Supramolecular Chemistry
Background:
- Superbases are crucial in organic synthesis and catalysis.
- Designing molecules with enhanced basicity requires understanding structure-property relationships.
- Extended hydrogen-bonding networks are a proposed mechanism for increasing basicity.
Purpose of the Study:
- To investigate the efficacy of extended hydrogen-bonding networks in creating superbases.
- To computationally evaluate the gas-phase proton affinities of novel superbase candidates.
- To identify the most potent superbase structures among various amine scaffolds.
Main Methods:
- Computational chemistry methods, specifically the ωB97X-D/6-311+G(2d,p) level of theory, were employed.
- Gas-phase proton affinities were calculated for 21 potential superbase molecules.
- The computational method was validated by benchmarking against 44 known experimental proton affinities of nitrogen bases.
Main Results:
- Extended hydrogen-bonding networks, including second and third layers, significantly enhance basicity.
- Calculated proton affinities were up to 20 kcal mol(-1) greater than that of bis(dimethylamino)naphthalene.
- Decalin base 25 and adamantane base 31 were identified as the strongest superbases in this study.
Conclusions:
- Extended hydrogen-bonding networks are a viable strategy for designing potent superbases.
- The decalin and adamantane scaffolds show exceptional promise for superbase development.
- Computational methods provide reliable predictions for superbase design and discovery.
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