Abstract
α-Keto thioesters, with two electrophilic carbon centres, have been found to react differently with β-keto esters and isocyanoacetates. They undergo base induced Knoevenagel-type condensation on the keto carbonyl group with β-keto esters, followed by intramolecular cyclization and water addition leads to highly substituted γ-hydroxybutenolides. On the other hand, substituted oxazole derivatives have been obtained using isocyanoacetates via nucleophilic displacement on the thioester carbonyl followed by intramolecular cyclization. Further functionalization of the γ-hydroxybutenolides is also demonstrated via a BF3.OEt2-mediated cation-driven nucleophilic addition of terminal alkynes to access multiply substituted butenolides. (Figure presented.).
Original language | English |
---|---|
Pages (from-to) | 2692-2698 |
Number of pages | 7 |
Journal | Advanced Synthesis and Catalysis |
Volume | 359 |
Issue number | 15 |
DOIs | |
State | Published - 7 Aug 2017 |
Externally published | Yes |
Keywords
- oxazoles
- rearrangement
- synthetic methods
- α-keto thioesters
- γ-hydroxybutenolides
ASJC Scopus subject areas
- Catalysis
- Organic Chemistry