Iridium cyanates

Cyanuric acid can also be prepared from HNCO (100). Isocyanic acid [75-13-8] can be synthesized directiy by oxidation of HCN over a silver catalyst (101) or by reaction of H2, CO, and NO (60—75% yield) over palladium or iridium catalysts at 280—450°C (102). Ammonium cyanate and urea are by-products of the latter reaction. 

While the majority of transition metal photocatalysts are based upon ruthenium and iridium complexes, similar intermolecular cyanation reactions can also be accomplished using gold-based transition metal photocatalysts. 

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