methyl 4-bromo-3,5-dichlorobenzoate

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: Methyl 4-bromo-3,5-dichlorobenzoate: CuBr2 (7.5 g, 34.08 mmol) in MeCN (50 mL) was stirred at 80° C. for 30 min. To this solution tert-butylnitrite (6.5 mL, 54.55 mmol) was added dropwise at the same temperature and the mixture was stirred for another 10 min. Methyl 4-amino-3,5-dichlorobenzoate in MeCN (30 mL) was added dropwise to the reaction mixture which was then stirred at 80° C. for 30 min. The reaction mixture was brought to ambient temperature. Aqueous ammonia solution (20 mL) was added and extracted with petroleum ether. The organic layer was washed with brine followed by water. The organic solution was dried (Na2SO4), filtered and concentrated to afford the title compound as an off white solid (7.5 g, 77%): 1H NMR (300 MHz, DMSO-d6) δ 8.02 (s, 2H), 3.94 (s, 3H); ESIMS m/z 282 ([M]+); IR (thin film) 1733, 762, 514 cm−1. was then stirred at 80° C. for 30 min was brought to ambient temperature extracted with petroleum ether The organic layer was washed with brine The organic solution was dried (Na2SO4) filtered concentrated

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

Procedure: Methyl 4-bromo-3,5-dichlorobenzoate: CuBr2 (7.5 g, 34.08 mmol) in MeCN (50 mL) was stirred at 80° C. for 30 min. To this solution tert-butylnitrite (6.5 mL, 54.55 mmol) was added dropwise at the same temperature and the mixture was stirred for another 10 min. Methyl 4-amino-3,5-dichlorobenzoate in MeCN (30 mL) was added dropwise to the reaction mixture which was then stirred at 80° C. for 30 min. The reaction mixture was brought to ambient temperature. Aqueous ammonia solution (20 mL) was added and extracted with petroleum ether. The organic layer was washed with brine followed by water. The organic solution was dried (Na2SO4), filtered and concentrated to afford the title compound as an off white solid (7.5 g, 77%): 1H NMR (300 MHz, DMSO-d6) δ 8.02 (s, 2H), 3.94 (s, 3H); ESIMS m/z 282 ([M]+); IR (thin film) 1733, 762, 514 cm−1. was then stirred at 80° C. for 30 min was brought to ambient temperature extracted with petroleum ether The organic layer was washed with brine The organic solution was dried (Na2SO4) filtered concentrated

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

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

Procedure: DIBAL-H (1M in toluene, 66 mL, and 66.0 mmol) was added dropwise to a stirred solution of methyl 4-bromo-3,5-dichlorobenzoate (7.5 g, 26.0 mmol) in THF (50 mL) at −78° C. The reaction mixture was allowed to warm toward ambient temperature and stirred for 6 h. The reaction mixture was poured into ice-water and extracted with CH2Cl2. The organic layer was washed with brine followed by water, dried (Na2SO4), filtered and concentrated to afford 6.0 g of a mixture of (4-bromo-3,5-dichlorophenyl)methanol and 4-bromo-3,5-dichlorobenzaldehyde—as an off white solid which was taken to next step without purification. extracted with CH2Cl2 The organic layer was washed with brine dried (Na2SO4) filtered concentrated

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

Procedure: 4-Bromo-3,5-dichlorobenzyl alcohol was prepared from methyl 4-bromo-3,5-dichlorobenzoate using stage (iii) of Process B and 4-bromo-3,5-dichlorobenzaldehyde using stage (iv) of Process B.

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

Procedure: Methyl 4-amino-3,5-dichlorobenzoate (32 g.) dissolved in 48% hydrobromic acid (100 ml.) was cooled to 0° and sodium nitrite (10.5 g.) was added. The solution was added slowly to a mixture of 48% hydrobromic acid (80 ml.) and cuprous bromide (35 g.) and the mixture heated at reflux for 2 hours. After cooling, the mixture was extracted with ethyl acetate and the organic extracts washed with brine, dried (anhydrous magnesium sulphate) and evaporated to give a dark solid. Crystallisation from ethyl acetate gave methyl 4-bromo-3,5-dichlorobenzoate (20 g.). Nuclear Magnetic Resonance Spectrum (NMR) was as follows: 1H: 4.0,3H,s; 7.9,2H,s. was cooled to 0° the mixture heated at reflux for 2 hours After cooling the mixture was extracted with ethyl acetate the organic extracts washed with brine dried (anhydrous magnesium sulphate) evaporated to give a dark solid Crystallisation from ethyl acetate

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

Procedure: Methyl 4-bromo-3,5-dichlorobenzoate: CuBr2 (7.5 g, 34.08 mmol) in MeCN (50 mL) was stirred at 80° C. for 30 min. To this solution tert-butylnitrite (6.5 mL, 54.55 mmol) was added dropwise at the same temperature and the mixture was stirred for another 10 min. Methyl 4-amino-3,5-dichlorobenzoate in MeCN (30 mL) was added dropwise to the reaction mixture which was then stirred at 80° C. for 30 min. The reaction mixture was brought to ambient temperature. Aqueous ammonia solution (20 mL) was added and extracted with petroleum ether. The organic layer was washed with brine followed by water. The organic solution was dried (Na2SO4), filtered and concentrated to afford the title compound as an off white solid (7.5 g, 77%): 1H NMR (300 MHz, DMSO-d6) δ 8.02 (s, 2H), 3.94 (s, 3H); ESIMS m/z 282 ([M]+); IR (thin film) 1733, 762, 514 cm−1. was then stirred at 80° C. for 30 min was brought to ambient temperature extracted with petroleum ether The organic layer was washed with brine The organic solution was dried (Na2SO4) filtered concentrated