Acetylene → 1,1-Dimethoxy-oct-7-yne

Participants

Reaction Steps

Acetylene was bubbled through ca. 300 ml of liquid ammonia while 8.1 g (0.35 atom) of sodium was added in small pieces. After the disappearance of the blue color, dimethylsulfoxide (150 ml) was added cautiously. 1,1-Dimethoxy-6-iodohexane (8.16 g; 0.3 Mole) was then added over a period of 10 min. while acetylene was bubbled through the stirred mixture. The ammonia was allowed to evaporate and was replaced with ether. When the mixture had reached 0°, dilute NH4Cl solution was added. The organic layer was separated, washed with water, dried (Na2SO4), and evaporated. Distillation of the residue gave 48.9 g (96%) of 1,1-dimethoxy-oct-7-yne, b.p. 91°/8 Torr.

Provenance & Evidence