Hydroxylamine → 2,5-dichloro-N-hydroxy-4,6-dimethylpyridine-3-carboximidamide

Participants

Reaction Conditions

Reaction Steps

A suspension of 2,5-Dichloro-4,6-dimethyl-nicotinonitrile (45.0 kg) and 50% hydroxylamine (59.2 kg) in the presence of catalytic amount of 1,10-phenanthroline monohydrate (0.680 kg) in methanol/water (214 kg/362 kg) is heated to 70-80° C. The mixture is agitated at 70-80° C. Water (353 kg) is added slowly into the resulting solution while the temperature is maintained at >79° C. The solution is cooled to 75° C. with stirring resulting in crystallization of (Z)-2,5-dichloro-N′-hydroxy-4,6-dimethylnicotinimidamide. The suspension is further cooled to 20° C., the solid is filtered off and the wet cake is washed with water (160 kg). (Z)-2,5-dichloro-N′-hydroxy-4,6-dimethylnicotinimidamide is dried under vacuum at max. 60° C. until residual water level is max 0.15% (KF).

Provenance & Evidence