4,4'-Difluorobenzophenone → Phthalonitrile

Temperatur

160 °C

To a 100 ml, 3-necked flask equipped with a thermometer and a Dean-Stark trap was added 5.0 gm (22.9 mmol) of 4,4'-difluorobenzophenone, 8.03 gm (23.9 mmol) of bisphenol A6F, and 50 ml of dimethylacetamide (DMAC). After flushing the mixture for 30 minutes with dry nitrogen, 3.9 gm (28.7 mmol) of pulverized anhydrous potassium carbonate was added with stirring. The reaction mixture was stirred at 70° C. for 1 hour. Toluene was added to the Dean-Stark trap and to the reaction vessel (4 ml). The reaction mixture was refluxed at 145°-150° C. for 24 hours. Water which formed as a by-product was removed by azeotropic distillation. The toluene was removed by distillation while heating to 160° C. Upon cooling to 50° C., 3.10 gm (17.9 mmol) of 4-nitrophthalonitrile was added. Since the reaction mixture was somewhat viscous, the temperature of the mixture was increased to 110° C. and held at this temperature for 18 hours (overnight). FTIR spectroscopy showed the absence of hydroxy and nitro bands. The room temperature mixture was then poured into 300 ml of water with stirring to break the precipitate into a powdery form. The solid precipitate was collected by suction filtration, washed exhaustively with water, and dried to afford 11.5 gm of oligomeric phthalonitrile monomer.

1. customTo a 100 ml, 3-necked flask equipped with a thermometer
2. additionwas added
3. stirringThe reaction mixture was stirred at 70° C. for 1 hour
4. temperatureThe reaction mixture was refluxed at 145°-150° C. for 24 hours
5. customwas removed by azeotropic distillation
6. customThe toluene was removed by distillation
7. temperatureUpon cooling to 50° C.
8. temperaturethe temperature of the mixture was increased to 110° C.
9. custom(overnight)
10. stirringwith stirring
11. filtrationThe solid precipitate was collected by suction filtration
12. washwashed exhaustively with water
13. customdried

ORD-Eintrag

ord-1d68e98a815848f2ac1359ef9e680312

Quelldatensatz

uspto-grants-1995_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05464926