2-Amino-5-chloropyridine → HCID 23345083, compound

Participants

Reaction Steps

5-Chloro-2-aminopyridine (450 grams; 3.5 moles) and 5000 ml. of 1,2-dichloroethane were slurried together. The flask was then purged with nitrogen and a cold water bath applied, resulting in a lowering of the temperature to 20° C. 2,6-Dichlorobenzoyl isocyanate (912 grams; 4.2 moles) was added dropwise over one hour, holding the temperature at <30° C. The reaction mixture was stirred for 10 minutes, the cold water bath was removed, and a hot tap water bath (about 55° C.) was applied. The flask temperature rose to 42° C. and was held at 40° C. for 30 minutes. TLC showed that all starting material had been reacted. Solvent was removed on a rotary evaporator, and the solid residue was slurried with 1 liter of methanol, chilled and filtered. Yield was 1177 grams. m.p. 219°-222° C. Identity of the product was confirmed by NMR and IR.

Provenance & Evidence