Reduction of the uranium metallocene, [η 5 -1,2,4-(Me 3 C) 3 C 5 H 2 ] 2

The reaction of base-free Ph 2 Be with 1, in toluene gaVe the carbene adduct Ph 2 Be(i-Pr-carbene) (1) as colorless crystal blocks. For comparison, the di-n-butyl ether adduct Ph 2 -Be(n-Bu 2 O) (2) was prepared from BeCl 2 and PhLi in a mixture of Et 2 O and n-Bu 2 O. Single-crystal X-ray determinations reVeal monomeric solid-state structures for both complexes.

Readily accessible and easy-to-use phenyliodine(III) dichloride, PhICl(2), has been established as an innovative and superior reagent for the one-electron oxidation of cerium(III) complexes, comprising amide, amidinate, and cyclopentadienyl derivatives. Its use allowed the successful synthesis and structural characterization of the first members of three new classes of chloro-functionalized (organo)cerium(IV) compounds, including the long sought-after Cp(3)CeCl.