Hydrochloric Acid → benzyl {2-(4-bromophenyl)-1-[1-[(dimethylamino)sulfonyl]-4-(2,2-dimethylbutyl)-1H-imidazol-2-yl]ethyl}carbamate

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Reaction Conditions

Reaction Steps

Hydrogen chloride (4 M in 1,4-dioxane) (2 mL, 8 mmol) was added to an ambient temperature solution of tert-butyl 2-[1-{[(benzyloxy)carbonyl]amino}-2-(4-bromophenyl)ethyl]-4-(2,2-dimethylbutyl)-1H-imidazole-1-carboxylate (for synthesis see Example 37) (600 mg, 1.03 mmol) in methanol (4 mL). After stirring at 70° C. for 1 h, volatiles were removed in vacuo. The residue was partitioned between methanol/ethyl acetate and 10% aqueous sodium hydroxide. The aqueous phase was extracted with ethyl acetate. The combined organic extracts were dried (magnesium sulfate) and concentrated in vacuo. Triethylamine (0.43 mL, 3.09 mmol) followed by dimethylsulfamoyl chloride (0.22 mL, 2.06 mmol) were added to an ambient temperature solution of the crude residue in methylene chloride (10 mL). After stirring at ambient temperature overnight, the reaction mixture was diluted with water and extracted with ethyl acetate and methylene chloride. The combined organic extracts were dried (magnesium sulfate) and concentrated in vacuo to afford benzyl {2-(4-bromophenyl)-1-[1-[(dimethylamino)sulfonyl]-4-(2,2-dimethylbutyl)-1H-imidazol-2-yl]ethyl}carbamate which was used in the subsequent step without further purification.

Provenance & Evidence