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Electrophile-Directed Diastereoselective Oxonitrile Alkylations
Sergiy V Chepyshev1, Bhaskar Reddy Pitta2, Saidi Reddy Vangala3
1Department of Chemistry, Drexel University, Philadelphia, PA, 19104, USA.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|January 13, 2018
Summary
This study demonstrates a new method for creating chiral molecules by selectively alkylating oxonitrile dianions. This efficient process installs two stereogenic centers, valuable for synthesizing bioactive heterocycles.
Area of Science:
- Organic Chemistry
- Stereoselective Synthesis
Background:
- Prochiral oxonitrile dianions are versatile synthetic intermediates.
- Chiral secondary alkyl halides are readily available electrophiles.
Purpose of the Study:
- To develop a diastereoselective alkylation method for installing two contiguous stereogenic centers.
- To explore the utility of this method in synthesizing chiral oxonitriles.
Main Methods:
- Reaction of prochiral oxonitrile dianions with chiral secondary alkyl halides.
- Analysis of stereochemical outcomes and conformational preferences.
Main Results:
- Efficient diastereoselective installation of two contiguous tertiary stereogenic centers.
- Propagation of electrophile chirality to the product.
- Demonstration of efficient discrimination among conformers.
Conclusions:
- This alkylation strategy provides a powerful route to complex chiral oxonitriles.
- The resulting oxonitriles are valuable precursors for bioactive heterocycles.
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