Some common heterocyclic compound, 774-47-0, name is 5,6-Difluoroindoline-2,3-dione, molecular formula is C8H3F2NO2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Recommanded Product: 774-47-0
Example 3 2-Amino-4,5-difluorobenzoic acid To a 2 liter four neck round bottom flask equipped with a mechanical stirrer, a condenser and a thermometer was charged 100 g of 5,6-difluoroisatin and 900 ml of aqueous 2.5N sodium hydroxide solution. The mixture was stirred until a homogeneous purple solution resulted. To this solution, and with external cooling (acetone/wet ice), was charged 162 ml of a 30% solution of hydrogen peroxide over a period of about 20 minutes. The reaction temperature never rose above 45C throughout the addition. After addition was complete, the reaction mixture was heated for 2 hours and was then cooled to room temperature. This mixture was then carefully quenched into a solution of 6N HCl (200 ml) in a 5 liter flask. The temperature stayed at about 15-20C throughout the addition. A 5 liter flask was used because of extensive foaming during the quench. The pH of the quench mixture was adjusted from about 5.0 to about 1.0 with concentrated hydrochloric acid as precipitation of the product caused stirring to slow down. To the reaction mixture was then added 260 ml of 50% NaOH solution to bring the pH up to 4.50. The mixture was filtered and the solids were sucked dry. The product was then dried in an oven at 40C and reduced pressure to obtain 95 g of the title compound, m.p. 180-181C. NMR(CDCl3 300 MHz): 7.56 (1H,dd,J=8 Hz, J=7 Hz), 6.68 (1H,dd,J=8 Hz, J=7 Hz).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 774-47-0, its application will become more common.
Reference:
Patent; PFIZER INC.; EP342849; (1990); A3;,
Indoline – Wikipedia,
Indoline | C8H9N – PubChem