Chemistry of Sulfur-containing Heterocycles : from Three-membered to Macrocycles

The following are new results developed by the present project.1。Sulfuration of anti-and syn-9，9‘-bibenzonorbornenylidenes by elemental sulfur produced episulfides in high yields with retention of the configuration of the original alkenes.2.Treatment of di-1-adamantylacetylene with disulfur dichloride furnished2，3-di-1-adamantyl-thiirene1-oxide，3，4-di-1-adamantyl-1，2-dithiete，and 1，2-di-1-adamantyl-2-thioxoethanone.3。Oxidation of tetrathiolanes，carrying two bulky substituents at the 5-position，with dimethyldioxirane，produced the corresponding tetrathiolane3，4-dioxides，the first vic-disulfoxide isolated in pure form。The 3，4-dioxides decomposed in solution at room temperature to give dithiirane1-oxides and a reactive species“S I D22ジエーD2O”。Deoxygenation of the dithiiranes1-oxides with Lawesson‘s reagent provided dithiiranes.4。Ring inversion energies of the trithiolane and pentathiepane rings were determined。A pair of conformational isomers was synthesized by making use of high inversion barrier of the pentathiepane ring.5。Monocyclic thiophene1-oxides，1-imides，and related species were synthesized，and their structures and reactivities were investigated.6。The parent thiophene1，1-dioxide and monosubstitued derivatives were synthesized and isolated for the first time，and their spectroscopic properties and reactivities were fully characterized.7。A wide variety of sulfur-containing large-membered heterocycles，such as thiophenophanes and crown thioethers，were synthesized。

The following are new results developed by the present project.1. Sulfuration of anti- and syn-9,9'-bibenzonorbornenylidenes by elemental sulfur produced episulfides in high yields with retention of the configuration of the original alkenes.2. Treatment of di-1-adamantylacetylene with disulfur dichloride furnished 2,3-di-1-adamantyl-thiirene 1-oxide, 3,4-di-1-adamantyl-1,2-dithiete, and 1,2-di-1-adamantyl-2-thioxoethanone.3. Oxidation of tetrathiolanes, carrying two bulky substituents at the 5-position, with dimethyldioxirane, produced the corresponding tetrathiolane 3,4-dioxides, the first vic-disulfoxide isolated in pure form. The 3,4-dioxides decomposed in solution at room temperature to give dithiirane 1-oxides and a reactive species "SィイD22ィエD2O". Deoxygenation of the dithiirane 1-oxides with Lawesson's reagent provided dithiiranes.4. Ring inversion energies of the trithiolane and pentathiepane rings were determined. A pair of conformational isomers was synthesized by making use of high inversion barrier of the pentathiepane ring.5. Monocyclic thiophene 1-oxides, 1-imides, and related species were synthesized, and their structures and reactivities were investigated.6. The parent thiophene 1,1-dioxide and monosubstitued derivatives were synthesized and isolated for the first time, and their spectroscopic properties and reactivities were fully characterized.7. A wide variety of sulfur-containing large-membered heterocycles, such as thiophenophanes and crown thioethers, were synthesized.