Hydrochloric Acid → HCID 19862561, compound

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Reaction Steps

3.30 g of 1-[N-formyl-N-(4-hydroxy-3,5-di-tert.-butylbenzyl)amino]imidazole are dissolved in 100 ml of absolute tetrahydrofuran. Into this solution there are injected at room temperature 20 ml of a 2 molar solution of borane-dimethyl sulfide complex [BH3.S(CH3)2 ] in toluene. The reaction mixture is subsequently heated to gentle reflux for 2 hours, cooled to 0°, treated with 20 ml of absolute methanol and heated for an additional 30 minutes. The solvent is removed completely by evaporation under reduced pressure on a rotary evaporator. The residual crystalline solid is triturated with n-hexane, removed by filtration and vacuum-dried for a short period. Thereupon, the solid obtained is suspended in 50 ml of absolute methanol and hydrogen chloride is introduced carefully while stirring up to saturation, whereby a clear solution results with strong warming. This solution is heated to gentle reflux for 1 hour and then evaporated under reduced pressure on a rotary evaporator. The residue is treated with 25 ml of ice-cold water, whereupon saturated sodium bicarbonate solution is added to a weakly alkaline reaction and the mixture is extracted three times with 25 ml of methylene chloride each time. The combined methylene chloride extracts are washed once with a small amount of water and subsequently with saturated sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and evaporated. The residue is recrystallized from ethyl acetate/n-hexane and there is obtained 1-[N-(4-hydroxy-3,5-di-tert.-butylbenzyl)-N-methylamino]imidazole of m.p. 139°.

Provenance & Evidence