Dichloromethane → methyl racemic-5-(3-hydroxy-1-piperidinyl)-2-oxo-2H-[1,2,4]oxadiazolo[2,3-a]pyrimidine-7-carbamate

Participants

Reaction Steps

5.6 G. of dimethyl racemic-6-(3-hydroxy-1-piperidinyl)-2,4-pyrimidine-dicarbamate-3-oxide are suspended in 100 ml. of methylene chloride and 100 ml. of water. The suspension is adjusted with concentrated sodium hydroxide to pH 12.7. The mixture is stirred for 1 hour, the two phases are then separated and the aqueous phase is adjusted to pH 3 with concentrated hydrochloric acid, a white precipitate separating out. This precipitate is filtered off and recrystallized from a mixture of methylene chloride and methanol, there being obtained pure methyl racemic-5-(3-hydroxy-1-piperidinyl)-2-oxo-2H-[1,2,4]oxadiazolo[2,3-a]pyrimidine-7-carbamate, having a melting point of 244°-247° C. (decomposition).

Provenance & Evidence