Synthesis of Isoxazolidinyl Epoxides by Oxone Treatment of 2,3-Dihydroisoxazoles in Acetone–Water Solution: A New Stereoselective Approach to Hydroxy-Substituted IsoxazolidinesThis work was supported by the Slovak Grant Agencies APVV, Bratislava (project no. APVV-14-0147), VEGA, Bratislava (project no. 1/0488/14), and ASFEU, Bratislava (ITMS project No. 26240120001 and 26240120025). This article was created with the support of the MŠVVaŠ of the Slovak Republic within the Research and Development Operational Programme for the project ‘University Science Park of STU Bratislava’ (ITMS project No. 26240220084) co-funded by the European Regional Development Fund.
Received: 27 July 2017
Accepted after revision: 12 September 2017
27 September 2017 (eFirst)
A practical and efficient synthesis of new class of isoxazolidinyl epoxides by direct treatment of 4,5-unsubstituted 2,3-dihydroisoxazoles with Oxone and NaHCO3 in acetone/water solution is described. All epoxidation reactions proceed with excellent anti-selectivity and provide stable products in very good yields. A concept for the development of stereoselective approach to 3,4-trans-hydroxy-substituted isoxazolidines, namely triazole derivatives as important molecules in medicinal chemistry is presented. The synthesis is characterized by highly syn-stereoselective conversion of epoxides to anomeric bromoisoxazolidines, which are found to be powerful reaction intermediates for the coupling reactions with various nucleophiles.