Thione S-imides / Thiaziridines / Thione S-sulfides (thiosulfines) / Sulfur heterocycles / Reaction mechanism N-(1-Adamantyl)hexafluorothioacetone S-imide (1) reacts product. The structure of 9 has been determined by X-ray diffraction analysis. The connectivity of the heterocyclic ring readily with aromatic thioketones 4aΟͺe to afford 1,4,2-dithiazolidines 5aΟͺe as products of [3 + 2] dipolar cycloadditions. in this product indicates that the mechanism of its formation must proceed by a different route involving another in situ Unexpectedly, cycloadducts 5d and 5e, obtained from thioxanthione (4d) and 4,4Π-(dimethoxy)thiobenzophenone (4e), generated sulfur-centered 1,3-dipole. Retrocycloaddition of the primary adamantanethione cycloadduct 13 liberates he-respectively, are found to decompose at room temperature and could not be isolated as pure compounds. Unlike aro-xafluorothioacetone, which is subsequently captured by Simide 1 to give tetrakis(trifluoromethyl)-1,4,2-dithiazolidine matic thiones, adamantanethione (4f) did not react with 1 at ambient temperature. However, reaction did occur upon 8 as a crystalline product. The structure of 8 has also been confirmed by X-ray diffraction analysis. heating in a sealed tube, and the new 1,4,2-dithiazolidine 9, bearing two adamantyl moieties, was isolated as the major