Reaktion #93214

Reaktionsgleichung

triethylamine

bisphenol A

cyanogen bromide

acetone

triethylamine

→

Bisphenol A Dicyanate

Ausbeute 86.4%

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturmaintained under a nitrogen atmosphere
2. 2
   Temperaturso as to maintain the reaction temperature at -5° C. to 0° C
3. 3
   Temperaturthe reactor was maintained at -2° C. to 5° C. for an additional 50 minutes (3000 s)
4. 4
   ExtraktionAfter 5 minutes (300 s) the water and product mixture was extracted with three 500 milliliter portions of methylene chloride
5. 5
   ExtraktionThe combined methylene chloride extract
6. 6
   Waschenwas washed with 500 milliliters of 5 percent aqueous hydrochloric acid
7. 7
   Waschenby washing with 800 milliliters of deionized water
8. 8
   Trocknenthen drying over anhydrous sodium sulfate
9. 9
   FiltrationThe dry methylene chloride solution was filtered
10. 10
    Sonstigesolvent removed by rotary evaporation under vacuum
11. 11
    SonstigeBisphenol A dicyanate (360.7 grams) was recovered in 86.4 percent yield as a white crystalline solid

Vorschrift

A 342.45 gram (1.5 moles) portion of bisphenol A, 333.68 grams (3.15 moles) of cyanogen bromide and 1000 milliliters of acetone were added to a reactor and maintained under a nitrogen atmosphere with stirring. The stirred solution was cooled to -5° C. then 305.09 grams (3.015 moles) of triethylamine was added to the reactor over a twenty-five minute (1500 s) period and so as to maintain the reaction temperature at -5° C. to 0° C. After completion of the triethylamine addition, the reactor was maintained at -2° C. to 5° C. for an additional 50 minutes (3000 s), followed by addition of the reactor contents to 1 gallon (3.79 l) of chilled deionized water. After 5 minutes (300 s) the water and product mixture was extracted with three 500 milliliter portions of methylene chloride. The combined methylene chloride extract was washed with 500 milliliters of 5 percent aqueous hydrochloric acid followed by washing with 800 milliliters of deionized water then drying over anhydrous sodium sulfate. The dry methylene chloride solution was filtered and solvent removed by rotary evaporation under vacuum. Bisphenol A dicyanate (360.7 grams) was recovered in 86.4 percent yield as a white crystalline solid. Infrared spectrophotometric analysis of a film sample of the product confirmed the product structure (disappearance of phenolic hydroxyl absorbance, appearance of --O--C≡N absorbance).

Quelle