Thiols added easily to acetylenic compounds in the presence of Et3B to give alkenyl sulfides in good yields. The reaction of acetylenes with 3-methyl-2-buten-1-thio1 gave dihydro-thiophene derivatives in one pot.
Nucleophilic attack of thiols on phenylacetylene (1) in liquidammonia at room temperature gave the corresponding Z-isomer of styryl sulfides in high yield stereoselectively. Reaction of 1 with Na2S also proceeded selectively to give Z,Z-distyryl sulfide (12). On the other hand, reaction with NaSH gave 12 besides E,Z-isomer as a minor product.
Treatment of alkyne with alkanethiol in the presence of a catalytic amount of cesium carbonate and a radical inhibitor in DMSO provides the corresponding adduct, (Z)-1-alkenyl alkyl sulfide, in good yield with high selectivity.
Nucleophilic addition of thiols to acetylenes in liquid ammonia
作者:A. N. Volkov、K. A. Volkova、E. P. Levanova、B. A. Trofimov