Selective synthesis of α-organylthio esters and α-organylthio ketones from β-keto esters and sodium S -organyl sulfurothioates under basic conditions

• Published in: Beilstein journal of organic chemistry Vol. 17; no. 1; pp. 234 - 244
• Main Authors: Kazmierczak, Jean C, Cargnelutti, Roberta, Barcellos, Thiago, Silveira, Claudio C, Schumacher, Ricardo F
• Format: Journal Article
• Language: English
• Published: Germany Beilstein-Institut zur Föerderung der Chemischen Wissenschaften 2021; Beilstein-Institut
• Subjects: bunte salts; Chemistry; c–c bond cleavage; Esters; Full Research Paper; Intermediates; Ketones; Salts; Sodium; Solvents; Sulfur; α-alkylthio esters; α-alkylthio ketones; β-keto esters; Bunte salts; α-alkylthio esters; β-keto esters; α-alkylthio ketones; C–C bond cleavage
• ISSN: 1860-5397; 2195-951X; 1860-5397
• DOI: 10.3762/BJOC.17.24

We described herein a selective method to prepare α-organylthio esters and α-organylthio ketones by the reaction of β-keto esters with sodium -benzyl sulfurothioate or sodium -alkyl sulfurothioate (Bunte salts) under basic conditions in toluene as the solvent at 100 °C. When 4 equivalents of a base were used, a series of differently substituted α-thio esters were obtained with up to 90% yield. On the other hand, employing 2 equivalents of a base, α-thio ketones were achieved after 18 h under air. Furthermore, after a shorter reaction time, the isolation of keto-enol tautomers was possible, revealing them as significant intermediates for the mechanism elucidation.