Hydroxylamine → 2-Amino-4,6-dimethyl-3-nitropyridine

Participants

Reaction Conditions

Reaction Steps

To 75 mL of stirred conc H2SO4 cooled to -5° C. (ice-salt bath) was added 4,6-dimethyl-2-nitroaminopyridine (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 NH4OH 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 NH2OH. The resulting yellow slurry was cooled to 0° C., filtered, washed with cold water (50 mL), and dried at room temperature to give a mixture of the title compound and the 5-nitro isomer in a 55:45 ratio (determined by 1H NMR). This mixture was used directly in the next step.

Provenance & Evidence