Reaction of the thermo-labile triazenide Na[tBu3SiNNNSiMe3] with CO2: formation of the imido carbonate (tBu3SiO)(Me3SiO)C&z.dbd;N-SitBu3 and carbamine acid (tBu3SiO)CONH2CCDC 948708 and 1521007. For crystallographic data in CIF or other electronic format see DOI: 10.1039/c7dt00173h

The thermo-labile triazenide Na[ t Bu 3 SiNNNSiMe 3 ] was prepared by the reaction of Me 3 SiN 3 with Na(thf) 2 [Si t Bu 3 ] in pentane at −78 °C. Treatment of Na[ t Bu 3 SiNNNSiMe 3 ] with an excess of carbon dioxide in pentane at −78 °C yielded the imido carbonate ( t Bu 3 SiO)(Me 3 SiO)C&z.dbd;N-Si t Bu 3 and the carbamine acid ( t Bu 3 SiO)CONH 2 along with other products. From the reaction solution we could isolate the imido carbonate ( t Bu 3 SiO)(Me 3 SiO)C&z.dbd;N-Si t Bu 3 and carbamine acid ( t Bu 3 SiO)CONH 2 . At first single crystals of the carbamine acid ( t Bu 3 SiO)CONH 2 (triclinic, space group P 1&cmb.macr;) were grown from this solution at room temperature. A second crop of crystals were obtained by concentrating the solution. The second charge consisted of the imido carbonate ( t Bu 3 SiO)(Me 3 SiO)C&z.dbd;N-Si t Bu 3 (monoclinic, space group P 2 1 / n ). A one-pot synthesis of ( t Bu 3 SiO)(Me 3 SiO)C&z.dbd;N-Si t Bu 3 and ( t Bu 3 SiO)CONH 2 was achieved by the reaction of Na[Si t Bu 3 ] with Me 3 SiN 3 and subsequent CO 2 treatment.