PREPARATION AND CHARACTERIZATION OF AN YDRIDOTRIS(3,5-DIMETHYLPYRAZOL-1-YL)BORATE]URANIUM COMPLEX

During the reaction of a uranium pellet with freshly sublimed elementa l iodine in THF, ring opening of the THF was observed and a U-IV speci es was obtained. Further reaction of the solution with Na[HB(3,5Me(2)p z)(3)] in THF at room temperature gave, after recrystallization, a gre en crystalline solid 2 formulated as [UI2{O(CH2)(4)I}{HB(3,5-Me(2)pz)( 3)}] on the basis of various analyses. This complex has also been prep ared by reaction of UI4 in THF with the potassium salt of the polypyra zolylborate. The mechanism of the ring-opening of THF is discussed.