Ammonia → HCID 19862543, compound

Participants

Reaction Steps

Variant (a): 200 mg of 1-(4-hydroxy-3,5-di-tert.-butylbenzylamino)-2-methylmercaptoimidazole are dissolved in 8 ml of ethanol together with 0.41 g of nickel(II) chloride.6H2O. This solution is cooled in an ice-bath and 0.7 g of sodium borohydride is added portionwise within 1 hour. After completion of the addition, the ice-bath is removed and the black reaction mixture is stirred at room temperature for an additional 4 hours. For the work-up, the mixture is again cooled and sufficient 2N hydrochloric acid is added so that the reaction mixture has an acidic reaction. The resulting mixture is stirred for a few minutes and treated with conc. ammonia up to an alkaline reaction. Subsequently, the mixture is filtered through a bed of siliceous earth and the filter cake is washed five times with methylene chloride. The organic phase of the filtrate is separated, washed twice with water, dried over sodium sulfate and evaporated. The crystalline residue is reprecipitated from methanol/water and there is obtained 1-(4-hydroxy-3,5-di-tert.-butylbenzylamino)imidazole in the form of colorless crystals of m.p. 171°-174°.

Provenance & Evidence