METHOD OF PRODUCING C-UREA Russian patent published in 2017 - IPC C07C273/04 C07B59/00 G01N33/497 G01N33/58 G01N33/62 

FIELD: chemistry.

SUBSTANCE: method includes interaction of carbon ¹³C-dioxide (¹³CO₂) with propylene oxide at a temperature of 90-100°C in the presence of catalytic system composed of zinc bromide and tetrabutylammonium bromide taken in the molar ratio of 1:2.0-6.2. The molar ratio of propylene oxide to the catalyst is 2000-5150:1. Herewith the feed of ¹³CO₂ into the reactor is stopped when the molar ratio of the feed gas to the starting propylene oxide reaches 0.93-0.98 mol/mol. The subsequent transformation of the formed ¹³C-propylene carbonate into ¹³C-urea is carried out under the action of ammonia, immediately loading all the necessary ammonia in an amount of 3 to 4 mol/mol relative to ¹³C-propylene carbonate.

EFFECT: invention allows to provide high economic production efficiency of ¹³C-urea and its low cost, and to simplify the synthesis technology.

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