8-FLUOROQUINOLINE

85percent sulfuric acid (623 g) was added to a 1 L reaction flask, and o-fluoroaniline (133 g, 1.2 mol) was added dropwise. Warm to 130°C and stir for 2 hours. The reaction temperature was controlled at 130°C, and the mixture was dropped with glycerol (121 g, 1.3 mol) and potassium iodide (3 g). The resulting solution was stirred at 130C for 18 hours after the addition was complete. The reaction solution was cooled to room temperature and slowly added to ice water. After the release, an aqueous solution of sodium hydroxide was added dropwise to adjust the pH to 8-9. Extract with methyl tert-butyl ether to concentrate the separated oil layer. The tert-butyl ether was re-distilled under high vacuum through a packed distillation column to obtain high-purity 8-fluoroquinoline (146 g). The rate is 83percent and the gas chromatogram content is 99.7percent.85percent sulfuric acid (623 g) was added to a 1 L reaction flask, and o-fluoroaniline (133 g, 1.2 mol) was added dropwise. Warm to 130°C and stir for 2 hours. The reaction temperature was controlled at 130°C, and the mixture was dropped with glycerol (121 g, 1.3 mol) and potassium iodide (3 g). The resulting solution was stirred at 130C for 18 hours after the addition was complete. The reaction solution was cooled to room temperature and slowly added to ice water. After the release, an aqueous solution of sodium hydroxide was added dropwise to adjust the pH to 8-9. Extract with methyl tert-butyl ether to concentrate the separated oil layer. The tert-butyl ether was re-distilled under high vacuum through a packed distillation column to obtain high-purity 8-fluoroquinoline (146 g). The rate is 83percent and the gas chromatogram content is 99.7percent.To the solution of concentrated sulfuric acid (2 mL) diluted with concentrated nitric acid (1 mL), was added dropwise 8- fluoroquinoline (3.76 g, 40.0 mmol) at 0°C. The resulting suspension was stirred at 0°C for 2h. The reaction mixture was poured into ice-water and filtered. The filter cake was added saturated Na2CC>3 aqueous solution to adjust pH to 7 and extracted with dichloromethane (20 mL x 2). The combined organic layer was evaporated. The residue was purified by silica gel column chromatography (petroleum ether/ethyl acetate = 30/1) to give the desired product (330 mg, 61percent) as a white solid. H NMR (400 MHz, CDC13) delta 9.16 (d, / = 8.4 Hz, 1H), 9.12 (s, 1H), 8.56-8.42 (m, 1H), 7.78-7.74(m, 1H), 7.53-7.48(m, 1H).STEP A: 5-nitro-General procedure: In a glovebox, a reactant as identified in Table 3 (1 equiv, 0.2 mmol) and TMAF (3 equiv, 0.6 mmol) were added to six 1 dram vial with stir bar. A 0.14 M solution of sulfuryl fluoride in DMF (2 equiv, 2.9 mL, 0.4 mmol) were added and each vial and were quickly sealed. Each vial was heated to the temperature indicated in Table 3 for 24 hours, and then cooled to room temperature before being diluted with ether. The organic layer of each reaction mixture was washed four times with water, dried over MgS04, filtered and concentrated. The crude material was purified by flash chromatography (20:1 pentane:ether). The yield of product for each reaction mixture is reported in Table 3