1-bromo-2,3,4,5,6-pentafluorobenzene

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:35.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 265.2 mL (1.95 mol, 525.353 g) bromopentafluorobenzene, 52.11 g (2.144 mol) magnesium powder and 216 mL (0.975 mol, 203.025 g) tetraethoxysilane are mixed together at room temperature and diethylether is added dropwise to the vigorously stirred solution until an exothermic reaction is observed (˜240 mL). The solution is stirred for 30 minutes after which additional 90 mL of Et2O is carefully added. After stirring at 35° C. for 16 h the mixture is cooled to room temperature and diethylether evaporated. An excess of n-heptane (˜600 mL) is added to precipitate the magnesium salts. Solution is filtrated and evaporated to dryness. The residue is fractionally distilled under reduced pressure to yield di(pentafluorophenyl)diethoxysilane. is carefully added is cooled to room temperature diethylether evaporated An excess of n-heptane (˜600 mL) is added to precipitate the magnesium salts Solution is filtrated evaporated to dryness The residue is fractionally distilled under reduced pressure

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a diethyl ether solution of isopropyl magnesium bromide, chloropentafluorobenzene is added at 0° C. to 40° C. under nitrogen with stirring in a period of thirty minutes, such that the isopropyl magnesium bromide is in 1.03 to 1.05 molar excess of the chloropentafluorobenzene. The mixture is stirred at 47° C. to 53° C.; after 5 to 10 hours, bromopentafluorobenzene is added to react with the excess isopropyl magnesium bromide, and the mixture is stirred at 25° C. for 1 hour. Any excess bromopentafluorobenzene is back-titrated in situ with isopropyl magnesium bromide to form more C6F5MgBr. The yield of C6F5MgBr is 96.1%, and 3.9% C6F5C1 remained, as determined by 19F NMR, using C6H5CF3 as a reference; no trace of iPrMgBr was seen with 1H NMR. the mixture is stirred at 25° C. for 1 hour

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Up to now, several synthetic reactions for pentafluorophenyl alkali metal salt are known. For example, a method of producing pentafluorophenyllithium through bromine-metal exchange reaction using relatively expensive bromopentafluorobenzene as a starting raw material for a source of pentafluorophenyl group and butyllithium is already known. For example, in Synthesis of Fluoroorganic Compounds, p. 190, Springer-Verlag (1985), pentafluorophenyllithium is prepared in diethylether-hexane at -70° C. and is reacted with sulfur dioxide to give lithium pentafluorophenylsulfenate with 94% yield. Also, a method of producing pentafluorophenyllithium through hydrogen-metal exchange reaction using pentafluorobenzene as a starting raw material for a source of pentafluorophenyl group and butyllithium is already known. For example, in J. Org. Chem., 29, 2385 (1964), pentafluorophenyllithium prepared from pentafluorobenzene and butyllithium is reacted with carbon dioxide gas to give pentafluorobenzoic acid wherein the reaction yield is unknown, but the purification yield, depending on reaction solvent system, is 68% in diethylether-hexane system, 80.9% in diethylether type and 82% in diethylether-tetrahydrofuran system respectively.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Up to now, several synthetic reactions for pentafluorophenyl alkali metal salt are known. For example, a method of producing pentafluorophenyllithium through bromine-metal exchange reaction using relatively expensive bromopentafluorobenzene as a starting raw material for a source of pentafluorophenyl group and butyllithium is already known. For example, in Synthesis of Fluoroorganic Compounds, p. 190, Springer-Verlag (1985), pentafluorophenyllithium is prepared in diethylether-hexane at -70° C. and is reacted with sulfur dioxide to give lithium pentafluorophenylsulfenate with 94% yield. Also, a method of producing pentafluorophenyllithium through hydrogen-metal exchange reaction using pentafluorobenzene as a starting raw material for a source of pentafluorophenyl group and butyllithium is already known. For example, in J. Org. Chem., 29, 2385 (1964), pentafluorophenyllithium prepared from pentafluorobenzene and butyllithium is reacted with carbon dioxide gas to give pentafluorobenzoic acid wherein the reaction yield is unknown, but the purification yield, depending on reaction solvent system, is 68% in diethylether-hexane system, 80.9% in diethylether type and 82% in diethylether-tetrahydrofuran system respectively.

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a diethyl ether solution of isopropyl magnesium bromide, chloropentafluorobenzene was added at 0 to 40° C. under nitrogen with stirring in a period of thirty minutes, such that the isopropyl magnesium bromide was in 1.03 to 1.05 molar excess of the chloropentafluorobenzene. The mixture was stirred at 47 to 53° C.; after 5 to 10 hours, bromopentafluorobenzene was added to react with the excess isopropyl magnesium bromide, and the mixture was stirred at 25° C. for 1 hour. Any excess bromo-pentafluorobenzene was back-titrated in situ with isopropyl magnesium bromide to form more C6F5MgBr. The yield of C6F5MgBr was 96.1%, and 3.9% C6F5Cl remained, as determined by 19F NMR, using C6H5CF3 as a reference; no trace of iPrMgBr was seen with 1H NMR. the mixture was stirred at 25° C. for 1 hour

Conditions: temp:70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A multinecked flash as described in Example 1 was charged with 5.0 g (0.020 mol) of bromopentafluoro-benzene, 2.37 g (0.020 mol) of 3-aminophenylacetylene, 0.096 g (0.137 mmol) of bis(triphenylphosphine) palladium II chloride, 0.148 g (0.564 mmol) of triphenylphosphine, and 0.06 g (0.315 mmol) of cuprous iodide. The reaction mixture was heated at 70° C. for 40 hours after which gas chromatography showed the reaction to be complete. The product mixture was cooled to room temperature and diluted with 75 ml of ether. Filtration of the insoluble triethylamine hydrobromide salt by-product followed by concentration of the filtrate gave 5.7 g, (0.02 mol) of crude product as a yellow solid. Short path distillation of the crude under reduced pressure gave 2.84 g (0.010 mol, 50% yield) of the product as a colorless liquid that crystallized on standing. the reaction The product mixture was cooled to room temperature Filtration of the insoluble triethylamine hydrobromide salt by-product gave 5.7 g, (0.02 mol) of crude product as a yellow solid Short path distillation of the crude under reduced pressure

Conditions: temp:70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A multinecked flash as described in Example 1 was charged with 5.0 g (0.020 mol) of bromopentafluoro-benzene, 2.37 g (0.020 mol) of 3-aminophenylacetylene, 0.096 g (0.137 mmol) of bis(triphenylphosphine) palladium II chloride, 0.148 g (0.564 mmol) of triphenylphosphine, and 0.06 g (0.315 mmol) of cuprous iodide. The reaction mixture was heated at 70° C. for 40 hours after which gas chromatography showed the reaction to be complete. The product mixture was cooled to room temperature and diluted with 75 ml of ether. Filtration of the insoluble triethylamine hydrobromide salt by-product followed by concentration of the filtrate gave 5.7 g, (0.02 mol) of crude product as a yellow solid. Short path distillation of the crude under reduced pressure gave 2.84 g (0.010 mol, 50% yield) of the product as a colorless liquid that crystallized on standing. the reaction The product mixture was cooled to room temperature Filtration of the insoluble triethylamine hydrobromide salt by-product gave 5.7 g, (0.02 mol) of crude product as a yellow solid Short path distillation of the crude under reduced pressure

Conditions: temp:35.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 265.2 mL (1.95 mol, 525.353 g) bromopentafluorobenzene, 52.11 g (2.144 mol) magnesium powder and 216 mL (0.975 mol, 203.025 g) tetraethoxysilane are mixed together at room temperature and diethylether is added dropwise to the vigorously stirred solution until an exothermic reaction is observed (˜240 mL). The solution is stirred for 30 minutes after which additional 90 mL of Et2O is carefully added. After stirring at 35° C. for 16 h the mixture is cooled to room temperature and diethylether evaporated. An excess of n-heptane (˜600 mL) is added to precipitate the magnesium salts. Solution is filtrated and evaporated to dryness. The residue is fractionally distilled under reduced pressure to yield di(pentafluorophenyl)diethoxysilane. is carefully added is cooled to room temperature diethylether evaporated An excess of n-heptane (˜600 mL) is added to precipitate the magnesium salts Solution is filtrated evaporated to dryness The residue is fractionally distilled under reduced pressure

Conditions: temp:190.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 4-iodonitrobenzene (15 g, 0.060 mol), bromopentafluorobenzene (14.9 g, 2.56 mL, 0.060 mol) and copper powder (30 g) was placed into a 50-mL J-Young glass tube and heated at 190° C. for 24 hours. The tube was cooled and the mixture was extracted exhaustively with dichloromethane. The solvent was removed and the residue was extracted with boiling hexane and filtered while hot. The solvent was removed and the resulting viscous solid was sublimed to obtain 4-nitro-2′,3′,4′,5′,6′-pentafluorobiphenyl as a yellow solid (11.0 g, 63% yield). was placed into a 50-mL J-Young glass tube The tube was cooled the mixture was extracted exhaustively with dichloromethane The solvent was removed the residue was extracted with boiling hexane filtered while hot The solvent was removed