Sulfuric Acid → 4-Trifluoromethyl-6-(4-trifluoromethyl-phenyl)-pyridazin-3-ylamine
Reaction equation
COC1C=CC(C[NH:8][C:9]2[N:10]=[N:11][C:12]([C:19]3[CH:24]=[CH:23][C:22]([C:25]([F:28])([F:27])[F:26])=[CH:21][CH:20]=3)=[CH:13][C:14]=2[C:15]([F:18])([F:17])[F:16])=CC=1.OS(O)(=O)=O>>[F:18][C:15]([F:16])([F:17])[C:14]1[CH:13]=[C:12]([C:19]2[CH:24]=[CH:23][C:22]([C:25]([F:28])([F:27])[F:26])=[CH:21][CH:20]=2)[N:11]=[N:10][C:9]=1[NH2:8]Participants
3
Conditions
- Temperature
- 5 °C
Procedure
(4-Methoxy-benzyl)-[4-trifluoromethyl-6-(4-trifluoromethyl-phenyl)-pyridazin-3-yl]-amine (example C.26 step 8) (6.48 g, 15 mmol) was added portionwise at 5° C. to conc. H2SO4 (d 1.83, 17.0 mL, 303 mmol).The deep purple solution was stirred for 5 min at 5° C. then the cooling bath was removed and stirring was continued for further 60 min at 23° C. The mixture was poured onto ice, made alkaline with 32% NaOH-sol., saturated with solid NaCl and extracted with THF and TBME, dried the organic layer over MgSO4. Removal of the solvent in vacuum left the title compound as a light yellow solid (4.44 g, 95%), which was used without further purification. MS (ISP) 308.1 [(M+H)+]; mp 186-190° C.