Dithio and Thiono Esters, 62 . Reactions of Alkanedithioic Acid Dianions with Iodine, Sulfur, and Tin Compounds

The monoanion of the alkanedithioic acid 1a is oxidized with hypervalent iodine compounds to form the 1,2‐dithiine 6 , the monoanion of 1b yields the 1,2,4‐trithiolane 7 and the dianions 2b, c furnish the 1,2,4,5‐tetrathianes 3b, c . With diphenyltin or dimethyltin dichlorides 8 the monoanions of 1b, c afford the monothioacyl or bisthioacyl organotin sulfides 10a–c or 11a, b respectively. When treated with lithium hexamethyldisilazane, 10b undergoes an intramolecular cyclization to the 1,3,2‐dithiastannetane 9b; 10a is deprotonated by triethylamine to the 1,3,5‐trithia‐2‐stanninane 13 . The dianion 2c reacts with diphenyltin dichloride 8 to yield the 1,3,2‐dithiastannetane 9d , with dimethyltin dichloride the 1,2,4‐trithiolane 16 is formed. 9d is cleaved by thionyl chloride, sulfur dichloride, and disulfur dichloride to give a complex mixture of the 1,2,4,5‐tetrathiane 3c and the cyclic polysulfides 1,2,3,4,5,6‐hexathiepane 18 , 1,2,3,5,6,7‐hexathiocane 19 and the 1,2,3,5,6‐pentathiepane 20 in varying amounts. Reaction of the dianion 2b with thionyl chloride leads to the formation of the 1,2,4,5‐tetrathiane 3b as main product; byproducts are cyclic polysulfides, the 1,2,3,5,6‐pentathiepane 21 and the 1,2,3,4,5,6‐hexathiepane 22 .