UI₄(1,4-dioxane)₂, [UCl₄(1,4-dioxane)]₂, and UI₃(1,4-dioxane)1.5: Stable and Versatile Starting Materials for Low- and High-Valent Uranium Chemistry

The uranium(III) and uranium(IV) iodide complexes UI 3 (1,4-dioxane) 1.5 and UI 4 (1,4-dioxane) 2 have been easily prepared in high yield by reacting uranium turnings with a 1,4-dioxane solution of iodine under mild conditions. The two complexes exhibit outstanding thermal stability and are excellent precursors to a variety of uranium(III), uranium(IV), and uranium(VI) alkoxide, amide, organometallic, and halide compounds, including a safe, room-temperature synthesis of [UCl 4 (1,4-dioxane)] 2, which is a useful synthetic alternative to UCl 4 .