Bringing Redox Reactivity to a Redox Inactive Metal Center – E–I (E = C, Si) Bond Cleavage with a Thorium Bis(α-diimine) Complex



As the reactivity of transition-metal complexes with redox-active ligands has gained significant attention in recent years, we have begun expanding to the actinides. Here, we report the synthesis, characterization, and reactivity of (MesDABMe)2Th(THF) {1, MesDABMe = [MesNC(Me)=C(Me)NMes]2–, Mes = 2,4,6-trimethylphenyl, THF = tetrahydrofuran}, which cleaves the C–I bond in CH3I with subsequent Th–I and C–C bond formation to produce (MesDABMe)(MesDABmath image)ThI {2, MesDABmath image = [MesN=C(Me)C(Me)2NMes]}. When 2 is crystallized in acetonitrile, the solvated adduct (MesDABMe)(MesDABmath image)ThI(NCCH3) (2-MeCN) is isolated. The reaction of 2 equiv. of 1 with Me3SiI produces (MesDABMe)2ThI (3) and Me3SiSiMe3. In 3, one MesDABMe ligand is now monoanionic and provides an electron to cleave the Si–I bond. This represents a rare example of the reactivity of thorium with a redox-active ligand.