Process for making 2,3-dihydro-p-oxathiins and their sulfoxides and sulfones
Abstract
Abstract 2,3-DIHYDRO-P-OXATHIINS ARE MADE BY REACTING AN A-MERCAPTOOXO COMPOUND OR A DIMER THEREOF WITH AN EQUIMOLAR AMOUNT OF AN OXIRANE IN THE PRESENCE OF AN INERT ORGANIC SOLVENT AND IN TE PRESENCE OF A BASE AT A TEMPERATURE BETWEEN ABOUT 0 AND 100*C. SO AS TO FRM THE CORRESPONDING ALKOXYLATED A-MERCAPTOOXO COMPOUND AND THEN SUBJECTING THE LATTER COMPOUND TO CYLIZATION IN THE PRESENCE OF AN INERT SOLVENT AND AN ACID CATALYST OR BY REACTION WITH AN EQUIMOLAR AMOUNT OF ANHYDROUS ZINC CHLORIDE OR PHOSPHORUS PENTOXIDE. THE THUS-OBTAINED 2,3-DIHYDRO-P-OXATHIIN MAY THEN BE OXIDIZED TO THE SULFONE OR SULFOXIDE. THE COMPOUNDS OF THE INVENTION ARE VALUABLE AS ANTIOXIDANTS FOR USE IN SYNTHETIC MATERIALS AND ELASTOMERS. THE PROCESS PERMITS OBTAINING OF THE PRODUCT AT HIGH YIELDS AND AT A HIGH RATE OF PURITY.
Inventors
- 👤 H Offermanns
- 👤 F Asinger
- 👤 P Scherberich
Bibliographic Details
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