3-chloro-2-hydroxy-4-methoxybenzaldehyde

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:; See reaction.notes.procedure_details.

Procedure: 3-chloro-2-hydroxy-4-methoxybenzaldehyde (1.48 g) is suspended in 15 ml of H2O and hydroxylamine-O-sulfonic acid (1.08 g) is added, along with 0.1 g of Na2SO4. After three hours an additional 15 ml of H2O is added. After a total of four hours the reaction mixture is treated with 8% NaHCO3 solution and then extracted into ether. Evaporation and trituration with hexane gives a solid product. Recrystallization from toluene/hexane gives 7-chloro-6-methoxy-1,2-benzisoxazole, mp 115°-118° C. extracted into ether Evaporation and trituration with hexane gives a solid product Recrystallization from toluene/hexane

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

Procedure: 3-chloro-2,4-dimethoxybenzaldehyde (2.75 g) is refluxed for 30 minutes in 20 ml of dichloroethane containing 1.8 g of AlCl3. The reaction mixture is then poured into H2O and extracted with CH2Cl2. Evaporation and recrystallization from isopropanol gives 3-chloro-2-hydroxy-4-methoxybenzaldehyde, mp 125° C. extracted with CH2Cl2 Evaporation and recrystallization from isopropanol

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

Procedure: 3-chloro-2,4-dimethoxybenzaldehyde (2.75 g) is refluxed for 30 minutes in 20 ml of dichloroethane containing 1.8 g of AlCl3. The reaction mixture is then poured into H2O and extracted with CH2Cl2. Evaporation and recrystallization from isopropanol gives 3-chloro-2-hydroxy-4-methoxybenzaldehyde, mp 125° C. extracted with CH2Cl2 Evaporation and recrystallization from isopropanol

Conditions: temp:15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 3-chloro-2-hydroxy-4-methoxybenzaldehyde (16.6 g) and sodium dihydrogenphosphate (34.7 g) in a mixed solvent of DMSO (180 mL)-water (45.0 mL) was added an aqueous solution (35.0 mL) of sodium chlorite (27.2 g) under ice-cooling, and the mixture was stirred at 15° C. for 16 hr. The reaction mixture was poured into saturated aqueous sodium carbonate solution, the mixture was diluted with water, and filtered, and the filtrate was extracted with petroleum ether/ethyl acetate=5:1. The aqueous layer was acidified with conc. hydrochloric acid to adjusted pH=1, and the mixture was extracted with ethyl acetate. The organic layer was washed with 1N hydrochloric acid, and dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to give the title compound (11.1 g). cooling filtered the filtrate was extracted with petroleum ether/ethyl acetate=5:1 the mixture was extracted with ethyl acetate The organic layer was washed with 1N hydrochloric acid dried over anhydrous sodium sulfate the solvent was evaporated under reduced pressure

Conditions: temp:15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 3-chloro-2-hydroxy-4-methoxybenzaldehyde (16.6 g) and sodium dihydrogenphosphate (34.7 g) in a mixed solvent of DMSO (180 mL)-water (45.0 mL) was added an aqueous solution (35.0 mL) of sodium chlorite (27.2 g) under ice-cooling, and the mixture was stirred at 15° C. for 16 hr. The reaction mixture was poured into saturated aqueous sodium carbonate solution, the mixture was diluted with water, and filtered, and the filtrate was extracted with petroleum ether/ethyl acetate=5:1. The aqueous layer was acidified with conc. hydrochloric acid to adjusted pH=1, and the mixture was extracted with ethyl acetate. The organic layer was washed with 1N hydrochloric acid, and dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to give the title compound (11.1 g). cooling filtered the filtrate was extracted with petroleum ether/ethyl acetate=5:1 the mixture was extracted with ethyl acetate The organic layer was washed with 1N hydrochloric acid dried over anhydrous sodium sulfate the solvent was evaporated under reduced pressure

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

Procedure: To a solution of 2-chloro-3-methoxyphenol (19.3 g) in 1,2-dichloroethane (150 mL) were added triethylamine (73.7 g), magnesium chloride (57.8 g) and paraformaldehyde (36.5 g), and the mixture was stirred at 70° C. for 4 hr under nitrogen atmosphere. The reaction mixture was poured into 1N hydrochloric acid, and the precipitate was removed by filtration, and washed with dichloromethane. The organic layer was washed with 1N hydrochloric acid and saturated brine, and dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to give the title compound (21.5 g). the precipitate was removed by filtration washed with dichloromethane The organic layer was washed with 1N hydrochloric acid and saturated brine dried over anhydrous sodium sulfate the solvent was evaporated under reduced pressure

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

Procedure: 3-chloro-2-hydroxy-4-methoxybenzaldehyde (1.48 g) is suspended in 15 ml of H2O and hydroxylamine-O-sulfonic acid (1.08 g) is added, along with 0.1 g of Na2SO4. After three hours an additional 15 ml of H2O is added. After a total of four hours the reaction mixture is treated with 8% NaHCO3 solution and then extracted into ether. Evaporation and trituration with hexane gives a solid product. Recrystallization from toluene/hexane gives 7-chloro-6-methoxy-1,2-benzisoxazole, mp 115°-118° C. extracted into ether Evaporation and trituration with hexane gives a solid product Recrystallization from toluene/hexane

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

Procedure: 3-chloro-2,4-dimethoxybenzaldehyde (2.75 g) is refluxed for 30 minutes in 20 ml of dichloroethane containing 1.8 g of AlCl3. The reaction mixture is then poured into H2O and extracted with CH2Cl2. Evaporation and recrystallization from isopropanol gives 3-chloro-2-hydroxy-4-methoxybenzaldehyde, mp 125° C. extracted with CH2Cl2 Evaporation and recrystallization from isopropanol

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

Procedure: 3-chloro-2,4-dimethoxybenzaldehyde (2.75 g) is refluxed for 30 minutes in 20 ml of dichloroethane containing 1.8 g of AlCl3. The reaction mixture is then poured into H2O and extracted with CH2Cl2. Evaporation and recrystallization from isopropanol gives 3-chloro-2-hydroxy-4-methoxybenzaldehyde, mp 125° C. extracted with CH2Cl2 Evaporation and recrystallization from isopropanol