Cl[C:2]1[C:7]([N+:8]([O-:10])=[O:9])=[CH:6][CH:5]=[CH:4][N:3]=1.[NH2:11][C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][N:13]=1>C(Cl)(Cl)Cl>[N:13]1[CH:14]=[CH:15][CH:16]=[CH:17][C:12]=1[NH:11][C:2]1[C:7]([N+:8]([O-:10])=[O:9])=[CH:6][CH:5]=[CH:4][N:3]=131.6 g of 2-chloro-3-nitro-pyridine and 56.5 g of 2-amino-pyridine were well mixed in a mortar and the mixture was slowly heated on an oil bath to the melting point. At 150° C. a lively reaction started and the temperature spontaneously rose to 160° C. The heating was suspended until the isothermic reaction ceased and heating at 150° C. was continued for 2 hours. The mixture was cooled and the fused mass was taken up in 500 ml of chloroform. The mixture was concentrated and was chromatographed over silica gel. Elution with about 3 liters of a 1-0.75-1.2 chloroform-benzene-ether mixture yielded unreacted 2-chloro-3-nitro-pyridine and evaporation of the eluent yielded 20 g of raw product which was crystallized from 95% ethanol to obtain 15.5 g (36% yield) of 2-(2-pyridylamino)-3-nitro-pyridine in the form of orange-yellow needles melting at 121°-123° C. The product was soluble in 2 N hydrochloric acid.
Wird geladen…