反应详情

14.1 g. 2,3-Diamino-1-[2-hydroxy-3-(3,4-dimethoxyphenethylamino)-propoxy]-benzene trihydrochloride are dissolved in 10 ml. water and 3.5 ml. glacial acetic acid, cooled to 5° C. and mixed with 2.07 g. sodium nitrite in 3.6 ml. water. The reaction mixture is then stirred for 2.5 hours at ambient temperature. The resultant sodium chloride is precipitated out by the addition of 480 ml. isopropanol. After filtration, the filtrate is evaporated, purified over a column of silica gel using methanol/ethyl acetate (2:1 v/v) as elution agent, mixed with ethereal hydrochloric acid and the hydrochloride so obtained is crystallized from ethanol. There are obtained 1.26 g. (10% of theory) 4-[2-hydroxy-3-(3,4-dimethoxyphenethylamino)-propoxy]-benzotriazole hydrochloride; m.p. 123°-124° C.

1. additionmixed with 2.07 g
2. customThe resultant sodium chloride is precipitated out by the addition of 480 ml
3. filtrationAfter filtration
4. customthe filtrate is evaporated
5. custompurified over a column of silica gel
6. washas elution agent
7. additionmixed with ethereal hydrochloric acid