Carbon Disulfide. IV. Reaction with Active Methylene Compounds. The Formation of 3,5-Bismethylene-1,2,4-trithiolanes

The three-sulfur compounds formed on oxidation of the β-keto dithio acids prepared by the reaction of active methylene compounds with base and carbon disulfide have been shown to be 3,5-bis(acylmethylene)-1,2,4-trithiolane derivatives. In several cases, two of the three possible geometrical isomers have been isolated and provisional stereochemical assignments have been made. The i.r. and u.v. spectra of the trithiolanes have been compared with those of corresponding 2,4-bis(acylmethylene)-1,3-dithie-tane derivatives (desaurins) and interpreted in terms of a strong conjugative interaction between the sulfur atoms and carbonyl groups.