A new 'Mitsunobu homocoupling' reaction using aldol adducts of kojic acid
| Autor: | Keijin Nakaguro, Yasuhito Morishima, Takeshi Nagasaki, Hideki Azuma, Reiko Kato |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
chemistry.chemical_classification
010405 organic chemistry Diisopropyl azodicarboxylate Organic Chemistry 010402 general chemistry 01 natural sciences Biochemistry Medicinal chemistry 0104 chemical sciences chemistry.chemical_compound Aldol reaction chemistry Drug Discovery Michael reaction Enol ether Racemic mixture Hydroxymethyl Aldol condensation Kojic acid |
| Zdroj: | Tetrahedron. 94:132314 |
| ISSN: | 0040-4020 |
| Popis: | In this study, we attempted to carry out the Mitsunobu 1,4-elimination using the kojic acid analog 3, which carries a hydroxymethyl group on C-6 introduced by aldol condensation, to obtain an effective Michael acceptor 4. To the ethyl acetate solution of 3 and Ph3P, diisopropyl azodicarboxylate was added quickly at 0 °C, resulting in the immediate generation of a yellow precipitate. NMR, mass spectrometry, and X-ray crystal structure analyses allowed to identify the precipitate as a diastereomeric/racemic mixture of dimeric compounds of 4. The dimerization reaction was hypothesized to occur through two major steps: (i) intramolecular dehydration of 3 by Mitsunobu reagents and (ii) homocoupling of the dehydration product 4 to form a new trans-carbon–carbon double bond. Presumably, the enol ether moiety of 4 acts as an electron donor and immediately attacks the α,β-unsaturated carbonyl group of another molecule via a reaction that can be dubbed “Mitsunobu homocoupling.” |
| Databáze: | OpenAIRE |
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