Regio- and stereoselective ring-opening reaction of 2-bromomethyl-1,3-thiaselenole
with thiols proceeded as nucleophilic attack at the selenium atom of seleniranium
intermediate affording unsaturated selanyl sulfides, (Z)-CH2=CHSCH=CHSeSR, in up to 93% yield. Dithiols were involved in this reaction giving
symmetrical polyunsaturated compounds with two S–Se bonds in 70–75% yields. Efficient
synthesis of 2-(organylsulfanyl)-2,3-dihydro-1,4-thiaselenines in 69–96% yields was
developed by the acid-catalyzed cyclization of the unsaturated selanyl sulfides. Mild
reaction conditions (room temperature) and short reaction times are important features
of this methodology.
Key words
2-bromomethyl-1,3-thiaselenole - unsaturated selanyl sulfides - seleniranium intermediates
- 1,4-thiaselenines - thiols
