Methanol → 1,6-Dicarbomethoxy-3-hexyne

Temperature

64 °C

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%).

1. additionto the mixture is added
2. stirringThe mixture is further stirred at 64° C. for 6 hours
3. customAfter completion of the reaction
4. concentrationthe mixture is concentrated under reduced pressure, and methanol
5. customis removed
6. additionWater (1.5 liter) and toluene (1 liter) are added to the resulting residue
7. stirringthe mixture is stirred
8. customThe aqueous layer is removed
9. washthe toluene layer is washed with water (1.5 liter)
10. concentrationThe toluene layer is concentrated under reduced pressure
11. customfurther evaporated under reduced pressure

ORD record

ord-31c3ea951ec84c8bad805f6c05485b80

Source dataset

uspto-grants-1993_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05191109