Chemistry of acetylenic ethers. LI: Introduction of alkylthio groups into acetylenic compounds and into other compounds with reactive hydrogen atoms by means of disulphides

Abstract

Acetylenic compounds RC = CH can be converted into acetylenic thioethers by treatment of the sodium or lithium alkynide with diethyl disulphide in liquid ammonia. This constitutes the easiest route to 1-ethylthio-I-alkynes I.Other compounds with "acidic" CH3, CH2 or CH groups can likewise be alkylthiolated; generally the product containing two geminal ethylthio groups is formed in excess.Disulphides RS-SR can be subjected to nucleophilic substitution ; carbanions, for instance, react with these compounds t o give a thioether and thiolate ion.In the literature a few examples of such conversions are recorded. The carbanions used were those in NaCH(S02R)Z 1, NaC(C&)3 z, RMgBr 3,495, RLi 2 , 6 . During these reactions a heterolytic cleavage of the -S-Sbond occurs, producing one RS@ and one RS@ particle, the first of which becomes attached to the carbanion.

Alkynes Between Main Group Elements: From Dumbbells via Rods to Squares and Tubes

“…The substitution of organylthiochloroacetylene 323 with sodium organothiolates 324, 269 and the reaction of lithium chloroacetylene (325) with dialkyldisulfides 326 afforded acetylenedithioether 311(1) in good yields (Scheme 68). 270 The reaction of β,β-dichlorovinyl organyl sulfides with thiols in the presence of potassium hydroxide (1:1:2.5) in DMF at 100 °C afforded also 311(1). 271 Further difunctional acetylenes which can be attacked at the sp centers by nucleophiles are the acetylene diiodonium salts 306 (Scheme 69).…”