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

ABSTRACT: We described herein a selective method to prepare ?-organylthio esters and ?-organylthio ketones by the reaction of ?-keto esters with sodium S-benzyl sulfurothioate or sodium S-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 ?-thio esters were obtained with up to 90% yield. On the other hand, employing 2 equivalents of a base, ?-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.

SUBMITTER: Kazmierczak JC

PROVIDER: S-EPMC7849251 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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

Kazmierczak Jean C JC Cargnelutti Roberta R Barcellos Thiago T Silveira Claudio C CC Schumacher Ricardo F RF

Beilstein journal of organic chemistry 20210126

We described herein a selective method to prepare α-organylthio esters and α-organylthio ketones by the reaction of β-keto esters with sodium S-benzyl sulfurothioate or sodium S-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 afte ...[more]

PMID: 33564334

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