反应详情

A solution of sodium nitrite (16.1 g) in water was added dropwise over a period of ca 0.75 h to a cold (salt-ice bath) stirred suspension of 4-benzyloxyaniline hydrochloride (50 g) in concentrated hydrochloric acid (120 ml). The temperature was kept between -6° and -12° during the addition and stirring was continued for 1 h at the same temperature. The mixture was filtered (Hyflo) and the filtrate cooled to ca -18°. The solution of the diazonium salt was then added to a cold (-12°) stirred solution of tin (II) chloride dihydrate (157.9 g) in concentrated hydrochloric acid (400 ml) over a period of ca 0.5 h. During the addition the temperature gradually rose to 0°, and subsequently stirring was continued for 2 h while allowing the reaction mixture to reach room temperature. Filtration of the suspension afforded a solid. This material was washed with anhydrous ether (750 ml) and dried at room temperature for ca 16 h to present the title compound as a powder (34.4 g) m.p. 165°-170°. T.l.c. (E), Rf 0.5.

1. additionThe temperature was kept between -6° and -12° during the addition
2. stirringstirring
3. filtrationThe mixture was filtered (Hyflo)
4. temperaturethe filtrate cooled to ca -18°
5. additionThe solution of the diazonium salt was then added to a cold (-12°)
6. stirringstirred solution of tin (II) chloride dihydrate (157.9 g) in concentrated hydrochloric acid (400 ml) over a period of ca 0.5 h
7. additionDuring the addition the temperature
8. customgradually rose to 0°
9. stirringsubsequently stirring
10. waitwas continued for 2 h
11. customto reach room temperature
12. filtrationFiltration of the suspension
13. customafforded a solid
14. washThis material was washed with anhydrous ether (750 ml)
15. customdried at room temperature for ca 16 h