反应详情

温度

90 °C

cis,cis-Muconic acid (265 g) is suspended in water (2 L) and the pH of the solution is adjusted to 5.1 with 10 M NaOH (250 mL). The mixture is heated at 90° C. for 2 hours. The progress of the isomerization is monitored by HPLC. After 2 hours of heating at 90° C., the mixture is treated with charcoal (20 g) for 30 minutes and the hot solution is filtered through a thin bed of Celite. The solution is adjusted to a pH of 2 with concentrated sulfuric acid (50 mL) and allowed to cool to 0° C. in an ice-bath. The precipitate is recovered by filtration and dried under reduced pressure overnight to yield 71 g cis,trans-muconic acid as light yellow solid. The filtrate is concentrated to 600 mL and allowed to incubate at 0° C. overnight. More precipitate is observed and is filtered and dried to yield an additional 152 g of cis,trans-muconic acid, an overall yield of 84 percent is achieved.

1. temperatureAfter 2 hours of heating at 90° C.
2. filtrationthe hot solution is filtered through a thin bed of Celite
3. temperatureto cool to 0° C. in an ice-bath
4. filtrationThe precipitate is recovered by filtration
5. customdried under reduced pressure overnight