Methanol → 1,6-Dicarbomethoxy-3-hexyne

Participants

Reaction Conditions

Reaction Steps

Toluene (796 g) is added to 1,4-dichloro-2-butyne (200 g, 1.63 mole), and to the mixture is added a mixture of methyl acetoacetate (568 g, 4.89 mole) and 28 % solution of sodium methylate in methanol (942 g, 4.89 mole) at room temperature. The reaction temperature is raised to 64° C., and the mixture is stirred for 9 hours. To the mixture is added additional 28 % solution of sodium methylate in methanol (94.2 g. 0.489 mole). The mixture is further stirred at 64° C. for 6 hours. After completion of the reaction, the mixture is concentrated under reduced pressure, and methanol is removed therefrom. Water (1.5 liter) and toluene (1 liter) are added to the resulting residue, and the mixture is stirred. The aqueous layer is removed, and the toluene layer is washed with water (1.5 liter). The toluene layer is concentrated under reduced pressure, and further evaporated under reduced pressure to give 1,6-dicarbomethoxy-3-hexyne (117.3 g, content; 96.3%).

Provenance & Evidence