Ethyl Acetate → 6-Chloropyridine-2,3-diamine

Participants

Reaction Conditions

Reaction Steps

A mixture of 12.0 g of 2-amino-6-chloro-3-nitropyridine, 78.0 g of tin(II) chloride dihydrate and 360 ml of a 9: 1 by volume mixture of ethyl acetate and 2-methyl-2-propanol was stirred at 60° C. for 1 hour, after which 1.32 g of sodium borohydride were added at 60° C., and the mixture was stirred for 3 hours at the same temperature. At the end of this time, the reaction mixture was freed from the solvent by distillation under reduced pressure. The resulting residue was diluted with water and neutralized by adding an aqueous solution of potassium carbonate, after which it was extracted with ethyl acetate. The extract was washed with an aqueous solution of sodium chloride and dried over anhydrous sodium sulfate, after which the solvent was removed by distillation under reduced pressure. The residue thus obtained was crystallized by trituration with a mixture of ethyl acetate and hexane, to give 6.50 g of title compound, melting at 120°-122° C.

Provenance & Evidence