4-bromo-2,6-dimethylaniline

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:0.00; pressure:0.00; stir:

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:0.00; pressure:0.00; stir:

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 4-Bromo-2,6dimethylaniline (4.49 g, 22.4 mmol) was taken up in water (25 ml) and concentrated hydrochloric acid (8.0 ml) was added. The mixture was sonicated to form a fine suspension and then cooled to 0° C. A solution of sodium nitrite (1.67 g, 24.2 mmol) in water (5 ml) was then added dropwise so as to maintain the temperature of the reaction between 0–5° C. The mixture was stirred at 0–5° C. for ½ h and then neutralised by addition of solid sodium carbonate. The resulting solution was then added portionwise to a solution of copper cyanide (2.42 g, 27.0 mmol) and potassium cyanide (3.65 g, 56.1 mmol) in water (25 ml) at 70° C. The mixture was stirred at 70° C. for ½ h, allowed to cool and then extracted with toluene (2 times). The combined extracts were washed with water and brine, dried over MgSO4, and concentrated in vacuo. The residue was purified by flash chromatography on silica (eluant EtOAc:pet. ether 5:95) to give an orange solid; yield 3.2 g (68%). The mixture was sonicated to form a fine suspension to maintain the temperature of the reaction between 0–5° C The mixture was stirred at 70° C. for ½ h to cool extracted with toluene (2 times) The combined extracts were washed with water and brine dried over MgSO4 concentrated in vacuo The residue was purified by flash chromatography on silica (eluant EtOAc:pet. ether 5:95) to give an orange solid

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 4-bromo-2,6-dimethylaniline (75 g, 0.37 mol) in distilled water (75 ml) is added concentrated sulphuric acid (75 ml), followed by brief heating to 60° C. for 1 hour until dissolution is complete. The mixture is allowed to cool to room temperature then further cooled to approximately 0° C. in an ice/salt bath. To this slurry is added an aqueous solution of sodium nitrite (25.33 g, 0.36 mol) in distilled water (126 ml) dropwise over 15 minutes, maintaining the temperature below 5° C., followed by additional stirring for 30 minutes. The reaction mixture is allowed to come to room temperature and then a solution of aqueous potassium iodide (187.6 g, 1.13 mol) in distilled water (190 ml) is added dropwise at room temperature. After the addition is complete the solution is briefly heated to 80° C. then allowed to cool to room temperature again. The reaction mixture is extracted with ethyl acetate (750 ml×3) and the organic phase is washed with 1M aqueous hydrochloric acid (200 ml) and aqueous sodium thiosulfate (2×200 ml). The organic phase is dried over anhydrous sodium sulphate and concentrated under reduced pressure. The residue is purified by column chromatography on silica gel to give 4-bromo-2,6-dimethyl-1-iodo benzene (75 g) as an orange liquid. to cool to room temperature then further cooled to approximately 0° C. in an ice/salt bath maintaining the temperature below 5° C. to come to room temperature After the addition is briefly heated to 80° C. to cool to room temperature again The reaction mixture is extracted with ethyl acetate (750 ml×3) the organic phase is washed with 1M aqueous hydrochloric acid (200 ml) and aqueous sodium thiosulfate (2×200 ml) The organic phase is dried over anhydrous sodium sulphate concentrated under reduced pressure The residue is purified by column chromatography on silica gel

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To (+/−)-3,5-dichloro-1-[1-(methoxymethyl)propyl]-2(1H)-pyrazinone (300 mg) and 4-bromo-2,6-dimethylaniline (238 mg) in THF (anhydrous, 9.4 mL) at 0° C. was added sodium bis(trimethylsilyl)amide (1.0 M/THF, 2.6 mL). The mixture was stirred at 0° C. for 10 minutes. Ethyl acetate (100 mL) was added and washed with water (25 mL) and brine (25 mL). The organic layer was dried over MgSO4 and concentrated and the crude product was chromatographed on silica gel using ethyl acetate/hexane (1:4) as eluent. The product was then crystallized from ethyl acetate/hexane to afford the title compound (419 mg). Elemental analysis calcd. for C17H21N3O2BrCl: C, 49.23; H, 5.10; N, 10.13. Found: C, 49.33; H, 5.05; N, 10.09. washed with water (25 mL) and brine (25 mL) The organic layer was dried over MgSO4 concentrated the crude product was chromatographed on silica gel The product was then crystallized from ethyl acetate/hexane

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