Reaktion #50729

Reaktionsgleichung

chloroacetone

1,1-dichloroacetone

1,3-dichloroacetone

Phenol

chloroacetone

chloroacetone

sulfuric acid

→

4,4'-Dihydroxy-alpha-methylstilbene

Lösungsmittel

acetone

water

methylene chloride

water

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturso as so maintain the reaction temperature at -10° C
2. 2
   SonstigeAfter two hours of post reaction at the -10° C. temperature
3. 3
   SonstigeThe oil solution is separated
4. 4
   Waschenthen washed with a second 500 milliliter portion of iced deionized water
5. 5
   SonstigeAfter separation
6. 6
   workup.ADDITIONthe recovered oil solution is added to a 2 liter beaker along with 250 milliliters of ethanol
7. 7
   workup.STIRRINGstirred
8. 8
   Sonstigeto provide a solution
9. 9
   Temperaturheating
10. 10
    TemperaturAs the temperature of the mixture increased
11. 11
    Temperaturheating
12. 12
    Sonstigereached 70° C.
13. 13
    Sonstigea massive precipitation of white crystalline plates
14. 14
    SonstigeThe oil layer is recovered by decantation of the water layer and 250 milliliters of ethanol
15. 15
    workup.ADDITIONis added
16. 16
    workup.ADDITIONDeionized water is again added to the stirred solution
17. 17
    Temperaturas heating
18. 18
    Sonstigereached 90° C.
19. 19
    Sonstigea massive precipitation of white crystalline plates
20. 20
    workup.STIRRINGAt this time, stirring
21. 21
    Temperaturboth chilled to 5° C.
22. 22
    FiltrationThe crystalline product is recovered by filtration
23. 23
    workup.STIRRINGthen stirred
24. 24
    Temperaturwith heating to 90° C
25. 25
    TemperaturAfter cooling to 5° C.
26. 26
    Filtrationthe crystalline product is recovered by filtration
27. 27
    Sonstigethen dried in a vacuum oven at 100° C.

Vorschrift

Phenol (376.44 grams, 4.0 moles), chloroacetone (205.62 grams, 2.0 moles as chloroacetone) and methylene chloride (300 grams) are added to a reactor and cooled to -10° C. with stirring. The chloroacetone used is a technical grade containing 90% chloroacetone, 2.5% acetone, 6.5% 1,1-dichloroacetone and 1.0% 1,3-dichloroacetone. Concentrated sulfuric acid (196.16 grams, 2.0 mole) is added dropwise to the stirred solution over a one hour period and so as so maintain the reaction temperature at -10° C. After two hours of post reaction at the -10° C. temperature, the viscous orange oil solution is mixed with 500 milliliters of iced deionized water. The oil solution is separated then washed with a second 500 milliliter portion of iced deionized water. After separation, the recovered oil solution is added to a 2 liter beaker along with 250 milliliters of ethanol and stirred to provide a solution. Deionized water (250 milliliters) is added to the stirred solution and heating commenced. As the temperature of the mixture increased, the stirred mixture began to clear. Each time clearing is observed, sufficient deionized water is added to induce cloudiness, followed by continuation of the mixing and heating. Once the temperature reached 70° C., a massive precipitation of white crystalline plates occurred and is followed by immediate coalesence of the precipitated product to an oil. The oil layer is recovered by decantation of the water layer and 250 milliliters of ethanol is added. Deionized water is again added to the stirred solution as heating commenced, in an amount sufficient to induce cloudiness each time clearing is observed. Once the temperature reached 90° C., a massive precipitation of white crystalline plates again occurred. At this time, stirring is stopped and the crystalline slurry, as well as the decanted water layer are both chilled to 5° C. and held therein for 12 hours. The crystalline product is recovered by filtration then combined with 250 milliliters of deionized water then stirred with heating to 90° C. After cooling to 5° C., the crystalline product is recovered by filtration then dried in a vacuum oven at 100° C. and 5 mm Hg to a constant weight of 243.3 grams. Proton magnetic resonance spectroscopy and infrared spectrophotometric analysis confirmed the product structure.

Quelle