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08:56
Synthesis of 1,2-Azaborines and the Preparation of Their Protein Complexes with T4 Lysozyme Mutants
Published on: March 25, 2017
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A Boron Protecting Group Strategy for 1,2-Azaborines
Andrew W Baggett1, Shih-Yuan Liu1
1Department of Chemistry, Boston College , Chestnut Hill, Massachusetts 02467-3860, United States.
Journal of the American Chemical Society
|October 3, 2017
Summary
Researchers developed a new method to remove alkyl and aryl groups from 1,2-azaborines, enabling their use as protecting groups. This breakthrough allows for the synthesis of novel BN isosteres relevant to biomedical and medicinal chemistry.
Area of Science:
- Organic Chemistry
- Medicinal Chemistry
- Synthetic Chemistry
Background:
- 1,2-azaborines are versatile heterocyclic compounds.
- B-alkoxide moieties in 1,2-azaborines are easily modified, limiting their use in certain reactions.
- Alkyl and aryl groups have not previously served as removable protecting groups for the boron position.
Purpose of the Study:
- To develop a method for facile deprotection of the boron position in 1,2-azaborines.
- To enable the use of alkyl and aryl groups as removable protecting groups for boron.
- To synthesize novel BN isosteres for biomedical and medicinal applications.
Main Methods:
- Reaction of 1,2-azaborines with molecular oxygen or di-tert-butylperoxide.
- Utilizing a copper(I) salt and an alcohol as catalysts.
- Employing N-deprotonated 1,2-azaborines for epoxide ring opening.
Main Results:
- Successful exchange of B-alkyl or B-aryl moieties for B-alkoxide fragments in 1,2-azaborines.
- Demonstration of alkyl and aryl groups as effective removable protecting groups for boron.
- Synthesis of a BN isostere of ethylbenzene, previously inaccessible.
- Access to BN isosteres of dihydrobenzofurans and benzofurans.
Conclusions:
- A novel and efficient method for boron deprotection in 1,2-azaborines has been established.
- This methodology broadens the synthetic utility of 1,2-azaborines in organic synthesis.
- The developed approach facilitates the creation of valuable BN isosteres for drug discovery and natural product synthesis.
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