H. J. BOONSTRA and J. F. ARENS ... (Laboratory of Organic Chemistry of the State University, Groningen, The Netherlands) ... Cis ethenylene- 1 ,Zbis-thioethers RSCH = CHSR can easily be prepared in liquid ammonia by treating cis or tvans 1,Zdichloro- ethylene with sodium amide and thiol. From these compounds acetylene thioethers HC =CSR can be ob- tained by means of sodium amide in liquid ammonia, followed by treatment with one mole of alkyl ...