Synthesis and crystal structure of [U($\eta$-$C_{5}$$Me_{5}$$)_{2}$(O$C_{4}$$H_{8}$$)_{2}$][B$Ph_{4}$], the first cationic cyclopentadienyl compound of uranium(III)
Résumé
The mixed amide complexes [U(NE$t_2$$)_2$(N{Si$Me_3$$\}_2$$)_2$] and [U($\eta$-$C_{8}$$H_{8}$)(NE$t_{2}$)(N{Si$Me_{3}$$\}_{2}$)] reacted in tetrahydrofuran (THF) with NE$t_{3}$HB$Ph_{4}$ to give the cations [U(NE$t_{2}$)(N{Si$Me_{3}$$\}_{2}$$)_{2}$(THF$)_{x}$$]^{+}$ and [U($\eta$-$C_{8}$$H_{8}$)(N{$Me_{3}$$\}_{2}$$)_{2}$(THF$)_{x}$$]^{+}$. The bis(trimethylsilyl) amide complex [U($\eta$-$C_{5}$$Me_{5}$$)_{2}$ (N{Si$Me_{3}$$\}_{2}$)] was inert towards NE$t_{3}$H B$Ph_{4}$ but its treatment with N$H_{4}$B$Ph_{4}$ afforded the cationic uranium(III) compound [U(($\eta$-$C_{5}$$Me_{5}$$)_{2}$ (THF$)_{2}$][B$Ph_{4}$], the crystal structure of which has been determined.