3,5-dibromo-4-hydroxybenzonitrile

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

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

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

Procedure: 10 g (0.092 mol) α-fluoroacryloyl chloride (obtained in accordance with example 1c) were added dropwise, at a temperature of 5° C., with stirring and in the course of 5 minutes, to a solution of 24.8 g (0.09 mol) of 3,5-dibromo-4-hydroxybenzonitrile and 9.1 g (0.09 mol) of triethylamine in 200 ml of anhydrous methylene dichloride, and the reaction mixture was then stirred for a further 30 minutes at the same temperature. The solid formed was filtered off and washed with 20 ml of anhydrous methylene dichloride. After 0.005 g of hydroquinone monomethyl ether had been added, the volatile constituents in the mixture of filtrate and wash solution were removed by distillation, and the residue was recrystallized from boiling n-heptane. 17.5 g (55% of theory) of 2,6-dibromo-4-cyanophenyl α-fluoroacrylate were obtained, melting point 135° to 138° C. The solid formed was filtered off washed with 20 ml of anhydrous methylene dichloride After 0.005 g of hydroquinone monomethyl ether had been added the volatile constituents in the mixture of filtrate wash solution were removed by distillation the residue was recrystallized

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

Procedure: 10 g (0.092 mol) α-fluoroacryloyl chloride (obtained in accordance with example 1c) were added dropwise, at a temperature of 5° C., with stirring and in the course of 5 minutes, to a solution of 24.8 g (0.09 mol) of 3,5-dibromo-4-hydroxybenzonitrile and 9.1 g (0.09 mol) of triethylamine in 200 ml of anhydrous methylene dichloride, and the reaction mixture was then stirred for a further 30 minutes at the same temperature. The solid formed was filtered off and washed with 20 ml of anhydrous methylene dichloride. After 0.005 g of hydroquinone monomethyl ether had been added, the volatile constituents in the mixture of filtrate and wash solution were removed by distillation, and the residue was recrystallized from boiling n-heptane. 17.5 g (55% of theory) of 2,6-dibromo-4-cyanophenyl α-fluoroacrylate were obtained, melting point 135° to 138° C. The solid formed was filtered off washed with 20 ml of anhydrous methylene dichloride After 0.005 g of hydroquinone monomethyl ether had been added the volatile constituents in the mixture of filtrate wash solution were removed by distillation the residue was recrystallized

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

Procedure: by mixing together a portion of the water, the diethylene glycol, the bromoxynil and the triethylamine (15% w/v of triethylamine represents a 2.6% by weight excess of triethylamine over the stoichiometric amount required to form bromoxynil triethylamine salt) with heating and stirring. The tristyryl phenol/ethylene oxide condensate was then added and the volume was made up to 100% by the addition of water.

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

Procedure: by mixing together a portion of the water, the diethylene glycol, the bromoxynil and the triethylamine (15% w/v of triethylamine represents a 2.6% by weight excess of triethylamine over the stoichiometric amount required to form bromoxynil triethylamine salt) with heating and stirring. The tristyryl phenol/ethylene oxide condensate was then added and the volume was made up to 100% by the addition of water.

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

Procedure: (I1B): To a suspension of 3,5-dibromo-4-hydroxybenzonitrile (2.11 g, 7.62 mmol) in acetic acid (70 mL) was added sodium nitrite (2.63 g, 38.1 mmol) in small portion, evolving bubbles and bromine were observed. After addition, the mixture was stirred at 50° C. overnight. Reaction was cooled to room temperature; water (250 ml) was added and extracted with EtOAc for two times. The combined extracts were washed with water and brine, dried over MgSO4 filtered and the filtrate was concentrated to give yellow orange solid. The solid was treated with small amount of MeOH, collected by filtration, rinsed with MeOH, dried to afford 1.56 g of 3-bromo-4-hydroxy-5-nitrobenzonitrile as yellow solid. After addition Reaction was cooled to room temperature extracted with EtOAc for two times The combined extracts were washed with water and brine dried over MgSO4 filtered the filtrate was concentrated to give yellow orange solid collected by filtration rinsed with MeOH dried

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

Procedure: (I1B): To a suspension of 3,5-dibromo-4-hydroxybenzonitrile (2.11 g, 7.62 mmol) in acetic acid (70 mL) was added sodium nitrite (2.63 g, 38.1 mmol) in small portion, evolving bubbles and bromine were observed. After addition, the mixture was stirred at 50° C. overnight. Reaction was cooled to room temperature; water (250 ml) was added and extracted with EtOAc for two times. The combined extracts were washed with water and brine, dried over MgSO4 filtered and the filtrate was concentrated to give yellow orange solid. The solid was treated with small amount of MeOH, collected by filtration, rinsed with MeOH, dried to afford 1.56 g of 3-bromo-4-hydroxy-5-nitrobenzonitrile as yellow solid. After addition Reaction was cooled to room temperature extracted with EtOAc for two times The combined extracts were washed with water and brine dried over MgSO4 filtered the filtrate was concentrated to give yellow orange solid collected by filtration rinsed with MeOH dried

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

Procedure: A mixture of 2.1 gm. (0.0076 mole) of 4-cyano-2,6-dibromophenol (m.p. 190.0°-191.5° C.), 40 ml. of toluene and 0.8 gm. (0.008 mole) of triethylamine was stirred in a system protected from atmospheric moisture by a `drying tube`, and to it there were added, in portions, a total of 2.0 grams (0.0075 mole) of 2,6-dichlorobenzylideneaminooxyacetyl chloride. The reaction mixture was then heated for an hour on the steambath; it was filtered hot, washing the triethylamine hydrochloride on the filter with hot toluene, then discarding it. The combined filtrates were evaporated to dryness under reduced pressure, and the residue was triturated with cold methanol, then filtered. The filter-cake was then washed with cold methanol and air-dried to obtain 3.3 gm. (85.6%) of colorless solid, m.p. 166°-168° C. This material was treated with boiling isopropyl alcohol and n-heptane mixture, and was then cooled in ice bath. The solid present was removed by filration, washed on the filter with n-hexane and dried in air to obtain 3.1 gm. of crystalline product melting at 168.0°-170.5° C. (uncorrected). A mixture of 2.1 gm drying tube`, and to it there were added, in portions The reaction mixture was then heated for an hour on the steambath it was filtered hot washing the triethylamine hydrochloride on the filter with hot toluene The combined filtrates were evaporated to dryness under reduced pressure the residue was triturated with cold methanol filtered The filter-cake was then washed with cold methanol air-dried to obtain 3.3 gm was then cooled in ice bath The solid present was removed by filration washed on the filter with n-hexane dried in air to obtain 3.1 gm

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

Procedure: To a suspension of 3,5-dibromo-4-hydroxybenzonitrile (10.0 g, 36.1 mmol) in 180 mL of chloroform was added pyridine (2.92 ml, 36.1 mmol). Chloromethylchloroformate (5.2 mL 60 mmol) was then added over 5 min. The mixture was allowed to stir at room temperature for 12 h. The reaction was then washed with 1% HCl aq, water, and brine. The organic layer was then dried over sodium sulfate, filtered, and evaporated to afford a white solid (12.5 g) in 94% yield. 1H-NMR (300 MHz, CDCl3) δ (ppm): 5.87 (d, 2H), 7.90 (s, 2H). 13C-NMR (300 MHz, CDCl3) δ (ppm): 73.58, 113.87, 115.68, 119.01, 136.40, 149.53, 149.71. Mp=83-85° C. The reaction was then washed with 1% HCl aq, water, and brine The organic layer was then dried over sodium sulfate filtered evaporated

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

Procedure: Bromoxynil and ioxynil.

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

Procedure: bromoxynil, and ioxynil.