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ChemicalBook CAS DataBase List 4,6-DIMETHYL-3-NITRO-PYRIDIN-2-YLAMINE
22934-23-2

4,6-DIMETHYL-3-NITRO-PYRIDIN-2-YLAMINE synthesis

5synthesis methods
-

Yield:-

Reaction Conditions:

with sulfuric acid in ethyl acetate;

Steps:

1.B Step B

Step B Preparation of 2-amino-3-nitro-4,6-dimethylpyridine To 75 mL of stirred conc H2 SO4 cooled to -5° C. (ice-salt bath) was added 4,6-dimethyl-2-nitraminopyridine (13.2 g, 79 mmol) portion-wise at such a rate as to maintain the internal temperature below -3° C. The mixture was warmed to 0° C. until homogeneous (30 minutes) at which time tlc (SiO2, 1:1 EtOAc/hexanes on a NH4 OH neutralized aliquot) indicated that the rearrangement was complete. The mixture was poured onto 400 g of crushed ice and the pH was adjusted to 5.5 by the addition of conc NH4 OH. The resulting yellow slurry was cooled to 0° C., filtered, washed with cold water (50 mL), and dried at room temperature to give 10.32 g of a mixture of the title compound and the 5-nitro isomer in a 55:45 ratio (determined by 1 H NMR). This mixture was used directly in the next step.

References:

US5151435,1992,A