Carbon-substituted compounds - carbamoyl phosphate

General-acid or -base catalysis is absent Hence 5 2 mechanisms are believed to be improbable. The mechanism for reaction of the monoanion is thought to involve the steps 

Similar steps have been proposed for other acylphosphates . Reaction (1) could involve a cyclic transition state including proton transfer. For the dianion, elimination of cyanic acid, viz. 

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