126-33-0

1953-99-7

1835-65-0

Example A Synthesis of 3,4,5,6-tetrafluorophthalonitrile: Anhydrous potassium fluoride (11.0 kg) was added to a 50 gallon stainless steel reactor. The salt was dried at 115°-138°C for 48 hours under 28 inches of vacuum. After the salt was cooled to 100°C, cyclobutanesulfone (19 liters) and tetrachlorophthalonitrile (4.74 kg) were added sequentially. The mixture was heated to 156°C within 30 minutes with stirring, followed by continued heating at 135°-162°C for 2.5 hours with vigorous stirring. Upon completion of the reaction, the mixture was cooled to 31°C (taking 15 minutes) and ice (69 kg) and softened water (119 liters) were added. After stirring the resulting mixture for 1.5 hours, the crude product was collected by centrifugation and washed with softened water (120 liters). The crude product was retransferred to a 50-gallon stainless steel still with deionized water (100 liters). Steam distillation was performed until 80 liters of distillate were collected. The distillate was cooled to 0°-5°C and the product was collected by centrifugation. The crystals were washed with softened water (2 x 90 l) to give 2.82 kg of wet product (LOD 6.4%; calculated yield: 74%). A small amount of the sample was vacuum dried at room temperature for two days and the melting point was measured to be 81°-83°C.