2-amino-4-chlorophenol

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

Procedure: A mixture of pent-4-ynimidic acid methyl ester (142 mg, 1.28 mmol) and 2-amino-4-chlorophenol (227 mg, 1.53 mmol) in dichloroethane (10 mL) was stirred for 2 days under reflux. The solvent was evaporated, the residue was partly dissolved in MeOH and filtered. The filtrate was concentrated, and the resulting crude residue was purified by flash chromatography (cyclohexane/AcOEt 9:1) to yield 18 mg (87 μmol, 7%) of 2-(but-3-ynyl)-5-chlorobenzo[d]oxazole. under reflux The solvent was evaporated the residue was partly dissolved in MeOH filtered The filtrate was concentrated the resulting crude residue was purified by flash chromatography (cyclohexane/AcOEt 9:1)

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

Procedure: 2-Amino-4-chlorophenol (316 mg, 2.2 mmol) and triethylamine (243 mg, 2.4 mmol) were dissolved in dichloromethane (5 mL). A solution of 3,5-dichlorobenzoyl chloride (419 mg, 2 mmol) in dichloromethane (2 mL) was added dropwise under ice cooling and argon atmosphere, and the mixture was stirred at room temperature for 15 hours. After the reaction mixture was diluted with ethyl acetate, washed with water and brine one after another, dried over anhydrous magnesium sulfate, the solvent was evaporated under reduced pressure. The obtained residue was purified by column chromatography on silica gel (n-hexane-ethyl acetate=3:1) to give a light brown solid. The solid was suspended and washed with n-hexane-ethyl acetate under heating at reflux to give the title compound (205 mg, 32.4%) as a white crystal. washed with water and brine one after another, dried over anhydrous magnesium sulfate the solvent was evaporated under reduced pressure The obtained residue was purified by column chromatography on silica gel (n-hexane-ethyl acetate=3:1) to give a light brown solid washed with n-hexane-ethyl acetate under heating at reflux

Conditions: temp:180.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Amino-4-chlorophenol (400 mg) and 4-piperidinecarboxylic acid (360 mg) were mixed with polyphosphate (2 g) in xylene (30 ml) and stirred with heating at 180° C. for 2 hours. After cooling to room temperature, the reaction was stopped by adding water. The filtrate was adjusted to pH 12 with 50% potassium hydroxide aqueous solution and extracted with methylene chloride. The organic layer was washed with saturated brine and dried with magnesium sulfate, and then the solvent was evaporated under a reduced pressure to obtain the title compound 5-chloro-2-(1-piperidyl)benzoxazole (218 mg). After cooling to room temperature extracted with methylene chloride The organic layer was washed with saturated brine dried with magnesium sulfate the solvent was evaporated under a reduced pressure

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

Procedure: A 2 g portion of 2-amino-4-chlorophenol was dissolved in 150 ml of ethanol, and the solution was mixed with 80 ml of carbon disulfide and 937 mg of potassium hydroxide and heated under reflux for 8 hours. The solvent was evaporated under a reduced pressure, and the residual oily mixture was mixed with 50 ml of 1 N hydrochloric acid aqueous solution and extracted with ethyl acetate. The organic layer was washed with saturated brine and dried with magnesium sulfate and then the solvent was evaporated under a reduced pressure. By recrystallizing the thus obtained mixture from ethyl acetate, the title compound (1.3 g) in light yellow color was obtained. heated under reflux for 8 hours The solvent was evaporated under a reduced pressure the residual oily mixture was mixed with 50 ml of 1 N hydrochloric acid aqueous solution extracted with ethyl acetate The organic layer was washed with saturated brine dried with magnesium sulfate the solvent was evaporated under a reduced pressure By recrystallizing the thus obtained mixture from ethyl acetate