“…Initially, at room temperature, CS 3 2– is produced in situ by reacting CS 2 and KOH in DMF, resulting in a dark red solution. , As the reaction temperature reaches 120 °C, CS 2 and S 2– are produced by the thermal decomposition of CS 3 2– . Considering that DMF can act as an oxidant to produce trisulfide radical anions (S 3 •– ) from S 2– , the semireduction of alkynes initiates with the addition of S 3 •– to the C–C triple bond of 1 to give I . This vinyl radical intermediate can abstract a hydrogen atom from water to generate II , leading to the formation of vinylic sulfide A after dissociation.…”