The reaction of UH
3 or U metal with triflic acid results in the formation of a mixture of species including U(OTf)
4and leads to the reproducible isolation of the mononuclear U(IV) hydroxo complex [U(OTf)
3(OH)(py)
4] (
1) and theU(IV) dinuclear
![](/images/entities/mgr.gif)
-oxo-complex [{U(OTf)
2(py)
3}
2{
![](/images/entities/mgr.gif)
-O}{
![](/images/entities/mgr.gif)
-OTf}
2] (
2). The X-ray crystal structures of these complexeshave been determined. Analytically pure complex
1 can be prepared in a 17-27% yield providing a good precursorfor the synthesis and study of the reactivity of the hydroxo complexes with different coordination environments.Two practical synthetic methods for the preparation of Lewis base adducts of U(OTf)
3 are described. Analyticallypure [U(OTf)
3(py)
4] (
4) was easily and reproducibly prepared (50-60% yield) by protonolysis of the amideU{N(SiMe
3)
2}
3 with pyridinium triflate in pyridine. Salt metathesis of UI
3(thf)
4 with potassium triflate in acetonitrileresulted in the complete substitution of the iodide counterions by triflate producing the acetonitrile solvate [U(OTf)
3(MeCN)
3]
n (
3). The solid-state structure of
3 shows the formation of a unique U(III) coordination polymer in whichthe metal ions are connected by three triflates acting as bidentate bridging ligands to form a 1D chain.