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Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
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Toward chiral polyhydroxylated dendrimers. Preparation and chiroptical properties
1Departments of Chemistry, University of Arizona, Tucson, Arizona 85721, and University of Connecticut, Storrs, Connecticut 06269, USA.
The Journal of Organic Chemistry
|June 8, 2000
Summary
Chiral dendrimers were synthesized and their optical activity accurately predicted using smaller model compounds. This confirms that the subunit conformations in dendrimers are similar to those in simpler molecules.
Area of Science:
- Organic Chemistry
- Supramolecular Chemistry
- Chiroptical Spectroscopy
Background:
- Dendrimers are highly branched macromolecules with unique properties.
- Chiral dendrimers offer potential applications in asymmetric synthesis and chiral recognition.
- Predicting the chiroptical properties of complex dendritic structures can be challenging.
Purpose of the Study:
- To synthesize novel chiral dendrimers containing vicinal diol subunits.
- To investigate the relationship between the optical activity of dendrimers and model compounds.
- To validate a modeling approach for predicting dendritic optical activity.
Main Methods:
- Preparation of four dendrimers (1b-4b) from acetonide-protected precursors (1a-4a).
- Measurement of optical activity ([Phi](d) values) for dendrimers and low molecular weight model compounds (5b-7b).
- Calculation and comparison of predicted [Phi](d) values for dendrimers based on model compound data.
Main Results:
- Successful synthesis of chiral dendrimers 1b-4b.
- Optical activity of dendrimers was accurately modeled using model compounds.
- Calculated [Phi](d) values for dendrimers agreed within 4.5% of observed values.
Conclusions:
- The optical activity of chiral dendrimers can be reliably predicted using simpler model compounds.
- Conformational equilibria of dendritic subunits are not significantly altered compared to model compounds.
- This modeling approach provides insights into the structure-property relationships of chiral dendrimers.
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