反应详情

A mixture of 2.92 g (0.008 mole) of 4-hydroxy-3-methoxymandelic acid (phenylmethyl) ester, 2 ml (0.02 mole) of 1-bromo-3-chloropropane, and 2.80 g (0.02 mole) of potassium carbonate in 40 ml of acetone was heated at reflux for 16 hours under nitrogen atmosphere during which time the solution changed from colorless to light-yellow. TLC (silica gel, hexanes/acetone 4:1) showed that the mandelate derivative had reacted, but 30-40% of unknown impurities had formed. The inorganic materials were separated by filtration, washed with acetone, and the filtrate was concentrated in vacuo at 60° C. to give 3.65 g of crude product. The material was purified by column chromatography (diameter 25 mm, using 80 g of silica gel) eluted with cyclohexane/ethyl acetate (6:1). The fractions containing the product were collected and the solid recrystallized from ethyl ether/hexanes to give 0.637 g (22%) of material as a white powder.

1. temperaturewas heated
2. temperatureat reflux for 16 hours under nitrogen atmosphere during which time the solution
3. customhad reacted
4. custom30-40% of unknown impurities had formed
5. customThe inorganic materials were separated by filtration
6. washwashed with acetone
7. concentrationthe filtrate was concentrated in vacuo at 60° C.
8. customto give 3.65 g of crude product
9. customThe material was purified by column chromatography (diameter 25 mm, using 80 g of silica gel)
10. washeluted with cyclohexane/ethyl acetate (6:1)
11. additionThe fractions containing the product
12. customwere collected
13. customthe solid recrystallized from ethyl ether/hexanes