benzoyl azide

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

Procedure: 4-(2-Hydroxy-3-tert.-butylaminopropoxy)-7-methyl-2-benzimidazolinone (prepared from the hydrochloride (see Example 3) and methanolic sodium methylate solution) is stirred for 5 days at ambient temperature with an equimolar amount of benzoic acid azide in dimethylformamide. The crystalline precipitate obtained is mixed with ethereal hydrochloric acid and, after evaporation, recrystallised from ethanol to give 4-[2-benzoyloxy-3-tert.-butylaminopropoxy]-7-methyl-2-benzimidazolinone hydrochloride; m.p. 216°-218° C. The crystalline precipitate obtained after evaporation recrystallised from ethanol