2,3-dichloro-4-phenyldiazenylphenol

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

Procedure: At 0 to 5° C., a solution of 7.6 g (0.11 mol) of NaNO2 in 12 ml of H2O is added dropwise to 50 ml of aqueous HCl (15%) and 9.8 g (0.105 mol) of aniline in a 100 ml two-neck flask fitted with internal thermometer and magnetic stirrer. After 10 minutes, this diazonium salt solution is added at 5 to 10° C. to a solution of 16.3 g (0.1 mol) of 2,3-dichlorophenol and 20 g (0.5 mol) of NaOH in 200 ml of H2O. The mixture is allowed to warm to room temperature, stirred for an additional 4 hours, neutralized with aqueous HCl and extracted 3× with 100 ml of ethyl acetate each. The combined organic phases are washed with NaCl solution and dried with Na2SO4, and the solvent is distilled off using a rotary evaporator. 31.8 g of (2,3-dichloro-4-hydroxyphenyl)phenyldiazene are obtained. fitted with internal thermometer and magnetic stirrer extracted 3× with 100 ml of ethyl acetate each The combined organic phases are washed with NaCl solution dried with Na2SO4 the solvent is distilled off a rotary evaporator