A complete series of uranocene(III) halides [{UCp″2X}n][X = F, Cl, Br, or I; Cp″=η-C5H3(SiMe3)2]; single-crystal X-ray structure determinations of the chloride and bromide (n= 2 for X–=µ-Cl– or µ-Br–)

Abstract

Reduction of [UCp″₂X₂][Cp″=η-C₅H₃(SiMe₃)₂; X = Cl, Br, or I] or [{UCp″₂(µ-BF₄)(µ-F)}₂] with Na/Hg in toluene yields the lipophilic (and n.m.r. characterisable) compounds [{UCp″₂X}_n](X = F, Cl, Br, or I), which are versatile precursors to uranocene (III or IV) compounds; X-ray data on the chloro- and bromo-derivatives reveal them to be the first uranocene(III) halide dimers (i.e., n= 2, with µ-X^–).