Reactions of alkanedithioic acid dianions with iodine, sulfur, and tin compounds

Article abstract of DOI:10.1002/cber.19961290612

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 triethylarnine 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. VCH Verlagsgesellschaft mbH, 1996.