8(<i>S</i>)-[(1<i>R</i>,2<i>S</i>,5<i>R</i>)-2-Isopropyl-5-methylcyclohexyloxy]-3,4-dihydro-2<i>H</i>-[1,4]dithiepino[2,3-<i>c</i>]furan-6(8<i>H</i>)-one

Abstract

The interaction of propane-1,3-dithiol with the chiral bis-thioether, which combines two 2(5H)-furanone moieties, bridged through their carbon atoms C(4) by the propane-1,3-dithiol fragment, in DMF in the presence of potassium hydroxide or cesium carbonate resulted in the formation of an optically active fused bicyclic sulfur heterocycle, possessing 1,4-dithiepine and unsaturated γ-lactone moieties. The studied reaction follows an unexpected pathway in a basic medium with the thiolate–thiolate exchange. The structure of the novel heterocycle of the 1,4-dithiepinofuranone series is characterized by single-crystal X-ray diffraction.

Keywords

• 2(5<i>H</i>)-furanone
• propane-1,3-dithiol
• <i>bis</i>-thioether
• trans-thiylation
• thiolate–thiolate exchange
• <i>S</i>,<i>O</i>-heterocycle