A Novel Method for the Synthesis of Substituted Tetrathia, Diselenadithia, and Tetraselenafulvalenes

Abstract

A one-step synthesis of tetrathia-, diselenadithia-, and tetraeelenafulvalenes at high pressure from CS2, CSSe, W e 2 , and acetylenes substituted with electron withdrawing groups such as COOH, COOCHj and CONH2 has been reported.Re- actions with CS2 were found to proceed best at pressures )4000 atm and at 75-100DC.Reaction times in excess of 10 hours were generally employed.CSSe was reacted similarly with these acetylene compounds.Lower temperatures (%60DC) were needed for reactions involving W e 2 , as this is known to be more reactive than CS2.Products were obtained in yields >85% and in a high degree of purity.Reactions with propiolic acid gave lower yields, as C02 was evolved from the reaction mixture.