317-20-4, A common compound: 317-20-4, name is 7-Fluoroisatin, belongs to indolines-derivatives compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.
N,N-dimethylformamide (540.0 mL, 6980 mmol, 100 mass%) was added to a 2-L ChemGlass reactor equipped with a mechanical agitator, a temperature probe, and a cooling/heating circulator. Next, 7-fluoroindoline-2,3-dione (135.0 g, 817.6 mmol, 100 mass%) was added at 25 C and dissolved to form a dark red solution. The charging ports and the beaker that contained the 7-fluoroindoline-2,3-dione were washed with N,N-dimethylformamide (135.0 mL, 1750 mmol, 100 mass%) and the rinse solution was poured into the reactor. Next, cesium carbonate 60-80 mesh (203.66 g, 625.05 mmol, 100 mass%) was added portion-wise to the reaction mixture. The addition was exothermic and the temperature of the reaction mixture increased from 20 to 25.5 C. The color of the reaction mixture changed from a dark red solution to a black solution. The reactor jacket temperature was set to 0 C. Next, iodomethane (56.5 mL, 907 mmol, 100 mass%) was added slowly via an additional funnel at ambient temperature, (iodomethane temperature) while maintaining the batch temperature at less than 30 C. Upon stirring, the reaction was exothermic, reaching a temperature of 29.3 C. The batch temperature decreased to 26.3 C after 85% of iodomethane was added, and the reaction mixture turned from black to an orange. After the addition of the iodomethane was completed, the jacket temperature was raised to 25.5 C. The reaction mixture was stirred at 25 C for 2 hrs. The reddish orange-colored reaction mixture was transferred to a 1 L Erlenmeyer flask. The reaction mixture was filtered through a ceramic Buchner funnel with a No.1 Whatman filter paper to remove solid CS2CO3 and other solid by-products. In addition to a light-colored powder, there were yellow to brown colored rod-shaped crystals on top of the cake, which were water soluble. The filtrate was collected in a 2-L Erlenmeyer flask. The solids cake was washed with N,N-dimethylformamide (100.0 mL, 1290 mmol, 100 mass%). The DMF filtrate was collected in a 2-L Erlenmeyer flask. To a separate 5-L ChemGlass reactor was charged water (3000.0 mL, 166530 mmol, 100 mass%). Next, 1.66 g of 7-fluoro-l-methylindoline-2,3-dione was added as seed to the water to form an orange colored suspension. The DMF filtrate was charged to the 5-L reactor slowly while maintaining the batch temp, at less than 29 C over a period of 60 min. Stirring was maintained at 290 rpm. The orange solids precipitated instantly. The 2-L Erlenmeyer flask was rinsed with N,N-dimethylformamide (55.0 mL, 711 mmol, 100 mass%) and charged to the 5-L reactor. The slurry was cooled to 25 C and agitated at 200 rpm for 12 hrs. The mixture remained as a bright orange-colored suspension. The slurry was filtered over a No. l Whatman filter paper in a 9 cm diameter ceramic Buchner funnel to a 4L Erlenmeyer flask to provide a bright orange-colored cake. The cake was washed with 1200 mL of water via rinsing the 5000 mL reactor (400 mL x 2), followed by 300 mL of deionized water introduced directly on the orange cake. The wet cake was dried under suction for 40 min at ambient temperature until liquid was not observed to be dripping from the cake. The cake was introduced into a vacuum oven (800 mbar) with nitrogen sweeping at ambient temperature for 1 hr, at 40-45 C for overnight, and at 25 C for 1 day to provide 7-fluoro-l-methylindoline-2,3-dione (Q, 130.02 g, 725.76 mmol, 100 mass%, 88.77% yield) as a bright orange-colored solid. NMR (400 MHz, DMSO- de) delta 7.57 (ddd, J=12.0, 8.5, 1.0 Hz, 1H), 7.40 (dd, J=7.3, 1.0 Hz, 1H), 7.12 (ddd, J=8.5, 7.5, 4.0 Hz, 1H), 3.29 (d, J=3.0 Hz, 3H). 13C NMR (101 MHz, DMSO-de) delta 182.3, 158.2, 148.8, 146.4, 137.2, 125.9, 124.3, 120.6, 28.7.
In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 7-Fluoroisatin, other downstream synthetic routes, hurry up and to see.
Reference:
Patent; BRISTOL-MYERS SQUIBB COMPANY; CARRASQUILLO, Ronald; GENG, Peng; HUANG, Eric C.; KATIPALLY, Kishta; LEE, Andrew; MUDRYK, Boguslaw; QIAN, Xinhua; RAZLER, Thomas M.; WANG, Jianji; WEI, Carolyn S.; WISNIEWSKI, Steven R.; ZHU, Ye; (79 pag.)WO2018/118830; (2018); A1;,
Indoline – Wikipedia,
Indoline | C8H9N – PubChem