2440-60-0

O-Methylisourea is a colorless crystal with a temperature of 44-45°C. It can evaporate with ethanol and ether vapors and absorb moisture and carbon dioxide from the air.

Methyl Carbamimidate is preparation of Ph (3-methoxy-1,2,4-thiadiazol-5-yl)carbamate from O-methylisourea hydrochloride.

O-methylisourea can be used in the synthesis of heterocyclic compounds; it is a guanylation reagent and a selective alkylating agent.

O-methylisourea hydrochloride is prepared in 69-80% yield by adding 1.15 equiv  HCl(g) with ice cooling to cyanamide dissolved in excess anhydrous methanol. The free base is obtained  from the salt using powdered KOH in a water-ether mixture or with sodium methoxide in methanol. The  monoacetate salt can be prepared from the free base with 1 equiv of HOAc. Drying: vacuum desiccator  over P2O5.

Salts are hygroscopic and should be stored in a desiccator even for  brief periods. Heating O-methylisourea to decomposition can liberate toxic fumes of NOx. Use in a fume  hood.