Reaktion #1583824

Reaktionsgleichung

5-bromo-2-chloroaniline

sodium nitrite

→

title compound

5-bromo-2-chlorophenylhydrazine hydrochloride

Lösungsmittel

hydrochloric acid

hydrochloric acid

water

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas cooled in an ice/salt bath
2. 2
   Temperaturwhile maintaining the temperature below 4° C
3. 3
   workup.STIRRINGThe resulting thick suspension was stirred for 2 h at 5° C.
4. 4
   Sonstigethe solid was isolated via filtration
5. 5
   Sonstigedried
6. 6
   Sonstigefurther dried
7. 7
   workup.ADDITIONby adding chlorobutane (500 mL)
8. 8
   Temperaturrefluxing
9. 9
   TemperaturAfter cooling
10. 10
    Sonstigethe solid was isolated by filtration

Vorschrift

A suspension of 5-bromo-2-chloroaniline (23 g, 0.11 mol) in concentrated hydrochloric acid (150 mL) and water (90 mL) was cooled in an ice/salt bath. A solution of sodium nitrite (8 g, 0.11 mol) in water (50 mL) was added dropwise to the reaction mixture while maintaining the temperature below 4° C. After stirring for 30 minutes the suspension was transferred via cannula to a solution of SnCl2 dihydrate in concentrated hydrochloric acid (170 mL) and cooled to 5° C. The resulting thick suspension was stirred for 2 h at 5° C. and the solid was isolated via filtration. The solid was air dried and then further dried by adding chlorobutane (500 mL) and refluxing using a Dean-Stark condenser. After cooling, the solid was isolated by filtration to afford the title compound as an off-white solid (35.3 g). 1H NMR (CD3COCD3): δ 10.25 (br s, 1H), 8.32 (br s, 2H) 7.38 (d, 1H), 7.30 (d, 1H), 7.16 (dd, 1H).

Quelle