反应详情

温度

-20 °C

6.54 g (30 mmol) methyl 4-amino-3-trifluoromethyl-benzoate are suspended in 50 ml 32% hydrochloric acid and cooled to −20° C. A solution of 2.28 g (33 mmol) sodium nitrite in 20 ml of water is added dropwise. The mixture is stirred for 3 hours at −20° to −10° C., then 27.08 g (120 mmol) tin-(II)-chloride dihydrate in 30 ml hydrochloric acid are added dropwise within 0.25 hours. The reaction mixture is stirred for 2 hours at −10° C., then acidified with cooling. The suspension is suction filtered through kieselguhr and washed with chloroform. The phases of the filtrate are separated, the aqueous phase is extracted with chloroform. The combined organic phases are dried and evaporated to dryness. The residue is precipitated as the hydrochloride, then stirred with diethyl ether.

1. stirringThe reaction mixture is stirred for 2 hours at −10° C.
2. temperaturewith cooling
3. filtrationfiltered through kieselguhr
4. washwashed with chloroform
5. customThe phases of the filtrate are separated
6. extractionthe aqueous phase is extracted with chloroform
7. customThe combined organic phases are dried
8. customevaporated to dryness
9. customThe residue is precipitated as the hydrochloride
10. stirringstirred with diethyl ether