1,2-Benzisoxazol-3(2H)-one,4-fluoro-(9CI)

4-Fluorobenzo[d]isoxazol-3-ol (4): To a 20L jacketed reactor were charged tetrahydrofuran (2.23 L) and 1 , 1 '-carbonyldiimidazole (0.910 Kg, 5.64 mol). The resulting mixture was stirred at 20°C. Then a solution of 2-fluoro-N, 6- dihydroxybenzamide (3) (744 g, 4.34 mol) in tetrahydrofuran (4.45 L) was slowly charged to the reactor maintaining the temperature below 30°C and stirred at 25°C for 30 min during which some off gassing was observed. The reaction mixture was heated to 60°C over 30 min and stirred for 6 h. The reactor was cooled to 20°C followed by the addition of 1 N aqueous hydrogen chloride (7.48L) over 15 min to adjust the pH to 1. The jacket temperature was set to 35°C and the reaction mixture concentrated under vacuum to remove approximately 6.68L of THF. The reactor was cooled to 15°C and stirred for 1 h. The resulting white slurry was filtered, the cake was washed with water (3.71 L) and dried in a vacuum oven at 40°C for 12 h. The desired product, (4) (597 g, 3.90 mol), was isolated in 90percent yield. 4-Fluorobenzo[d]isoxazol-3-ol (4): To a 20L jacketed reactor were charged tetrahydrofuran (2.23 L) and 1 , 1 '-carbonyldiimidazole (0.910 Kg, 5.64 mol). The resulting mixture was stirred at 20°C. Then a solution of 2-fluoro-N, 6- dihydroxybenzamide (3) (744 g, 4.34 mol) in tetrahydrofuran (4.45 L) was slowly charged to the reactor maintaining the temperature below 30°C and stirred at 25°C for 30 min during which some off gassing was observed. The reaction mixture was heated to 60°C over 30 min and stirred for 6 h. The reactor was cooled to 20°C followed by the addition of 1 N aqueous hydrogen chloride (7.48L) over 15 min to adjust the pH to 1. The jacket temperature was set to 35°C and the reaction mixture concentrated under vacuum to remove approximately 6.68L of THF. The reactor was cooled to 15°C and stirred for 1 h. The resulting white slurry was filtered, the cake was washed with water (3.71 L) and dried in a vacuum oven at 40°C for 12 h. The desired product, (4) (597 g, 3.90 mol), was isolated in 90percent yield.

Molecular Weight:153.11
XLogP3:1.2
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Exact Mass:153.02260653
Monoisotopic Mass:153.02260653
Topological Polar Surface Area:38.3
Heavy Atom Count:11
Complexity:185
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes