反应详情

温度

120 °C

A stirred autoclave was charged, at room temperature, with 65.85 g (715 mmol) of glycerol, 1.80 g (17.6 mmol) of valeric acid, 0.18 g (10 wt %) of AMBERLYST® (a polymer based catalyst) 35 resin and 0.39 g (1.0 mol %) of Pd/C at 5%. The autoclave was then pressurized at 50 bar of dihydrogen gas H2, and then it was heated at 120° C. for 16 h, stirring vigorously. After 16 h of reaction, the reaction mixture was brought back to room temperature. The catalyst was filtered on a MILLIPORE® filter (a membrane filter) (0.1 μm) and was rinsed with absolute ethanol. The solvents were evaporated and the organic products were extracted from the glycerol phase by extraction with CH2Cl2 (3×50 ml). The organic phase was washed with water (2×30 ml) and the CH2Cl2 was then evaporated at reduced pressure. The crude reaction product was purified on a flash silica column (eluent: cyclohexane/ethyl acetate=4:1˜1:1). 1-O-pentyl-glycerol ether was obtained at an isolated yield of 69%. After the reaction, the mixture of catalysts (AMBERLYST® (a polymer based catalyst) 35 resin and Pd/C) was immersed in 5 ml of methanol, and then transferred to the autoclave. The latter was dried under an argon stream for 4 h at room temperature. After complete evaporation of the solvent, the substrates (glycerol and valeric acid) were added for a fresh reaction (cf. example 31).

1. customAfter 16 h of reaction
2. customwas brought back to room temperature
3. filtrationThe catalyst was filtered on a MILLIPORE®
4. filtrationfilter (a membrane
5. filtrationfilter) (0.1 μm)
6. washwas rinsed with absolute ethanol
7. customThe solvents were evaporated
8. extractionthe organic products were extracted from the glycerol phase by extraction with CH2Cl2 (3×50 ml)
9. washThe organic phase was washed with water (2×30 ml)
10. customthe CH2Cl2 was then evaporated at reduced pressure
11. customThe crude reaction product
12. customwas purified on a flash silica column (eluent: cyclohexane/ethyl acetate=4:1˜1:1)