First Structurally Characterized Actinide Isocyanates

The synthesis and characterization of the neutral uranylisocyanate
UO2(NCO)2(OP(NMe2)3)2 [crystal data:  monoclinic, P21/c, a =
8.512(2) Å, b = 10.931(2) Å, c = 14.329(3) Å, β = 103.923(3)°,
V = 1294.0(4) Å3, Z = 2] and isocyanato uranate (Et4N)6[(UO2)2(NCO)5O]2· 2CH3CN·H2O [crystal data:  monoclinic, P21/c, a =
17.2787(2) Å, b = 15.560(1) Å, c = 32.7619(4) Å, β =
94.0849(5)°, V = 8786.5(2) Å3, Z = 4] are reported. Not only are
these compounds the first unambiguously characterized uranium
isocyanates regardless of the oxidation state for uranium, but they
are also the first structurally characterized actinide isocyanates.
Both compounds show coordination of the OCN moiety through
nitrogen to uranium and were characterized using IR and 1H, 13C,
14N, and 31P NMR spectroscopy and X-ray diffraction.