Hydrochloric Acid → HCID 135407154, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzoic acid hydrazine (2.8 g, 10.6 mmol) in ethanol (140 ml) and water (50 ml) is added 1N HCl (16 ml) and sodium cyanate (1.03 g, 16 mmol). The reaction mixture is stirred at room temperature for 30 minutes and at 35° C. for five minutes. The reaction mixture is cooled, evaporated, and partitioned between water (100 ml) and ethyl acetate (100 ml). The organic layer is dried (MgSO4) and evaporated. The crude product is cyclized by refluxing a solution in 1N NaOH (2-3 equiv.) for two hours. It is neutralized with 1N HCl and extracted with ethyl acetate. Pure 5-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]-2,4-dihydro-3H-1,2,4-triazol-3-one (0.32 g, 10%) is separated from 3,5-di-t-butyl-4-hydrox-ybenzoic acid by flash chromatography (silica, EtOAc), mp 276°-280° C.

Provenance & Evidence