Direct conversion of cinnamate esters into β,β-disubstituted ketones mediated by cyano-magnesio cuprates
| Autor: | Douglas T. Genna, Gary H. Posner |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
chemistry.chemical_classification
Substitution reaction Allylic rearrangement Ketone 010405 organic chemistry Stereochemistry Carboxylic acid Organic Chemistry Alcohol 010402 general chemistry 01 natural sciences Biochemistry 0104 chemical sciences chemistry.chemical_compound chemistry Nucleophile Drug Discovery Cinnamates Protecting group |
| Zdroj: | Tetrahedron. 72:5968-5971 |
| ISSN: | 0040-4020 |
| DOI: | 10.1016/j.tet.2016.05.003 |
| Popis: | The clean synthesis of unsymmetrical ketones from carboxylic acid derivatives has been a challenge in the organic community dating back over 80 years. Herein we report the conversion of simple alkyl cinnamates to β,β-disubstituted ketones with cyano-magnesio cuprates in high yields with no observation of tertiary alcohol byproduct. The lack of tertiary alcohol is attributed to a putative enolate intermediate that serves as a ketone protecting group. A distinctive steric inhibition trend was observed related to both the size of the R group on the parent ester and the nucleophilic cuprate. Lastly, we demonstrate that this reaction can be coupled with known copper mediated allylic substitution reactions yielding β,γ-disubstituted ketone (8) from parent α-chloro-β,γ-ethylenic ester (7). |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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