Phosphorus trichloride → Diethyl 5-nitropyridine-2,3-dicarboxylate

Participants

Reaction Conditions

Reaction Steps

88.8 g (0.648 mol) of phosphorus trichloride were added in the course of 30 minutes while stirring at 25° C. to a mixture of 92 g (0.324 mol) of the above N-oxide and 300 ml of 1,2-dichloroethane. After stirring at 25° C. for 12 hours, the reaction mixture was concentrated in vacuo, the residue was taken up again in methylene chloride and the solution was poured into 2.5 l of ice-water. After phase separation, the aqueous phase was extracted with methylene chloride. The organic extract was washed with water, saturated sodium hydrogencarbonate and sodium chloride solution, dried over magnesium sulfate and filtered off with suction through neutral alumina and silica gel. After concentrating, 58.2 g (67% of theory) of the title compound were obtained as a yellowish syrup. 1H-NMR, 400 MHz (CDCl3) δ: Ar 9.0 (d/1H), 9.55 (d, 1H)

Provenance & Evidence