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The use of redox-active ligands with the f-block elements has been employed to promote unique chemical transformations and explore their unique emergent electronic properties for a myriad of applications. In this study, we report eight new tris(amido) metal complexes: 1–Ln (Ln = Tb3+, Dy3+, Ho3+, Er3+, Tm3+, and Yb3+), 1–La, and 1–Ti (an early transition metal analogue). The one-electron oxidation of the tris(amido) ligand was conducted to generate semi-iminato complexes 2–Ln, 2–La, and 2–Ti, and these complexes were studied using EPR. Tris(amido) complexes 1–Ln, 1–La, and 1–Ti were fully characterized using a range of spectroscopic (NMR and UV–vis/NIR) and physical techniques (X–ray diffraction and cyclic voltammetry, with the exception of 1–La). Computational methods were employed to further elucidate the electronic structures of these complexes. Lastly, complexes 1–Ln, 1–La, and 1–Ti were probed as catalysts for alkyl–alkyl cross-coupling, and the initial rate of the reaction was measured to explore the influence of the metal ion. 

Catalytic site-selective hydroallylation of vinyl arenes and 1,3-dienes is reported. Transformations are promoted by a readily accessible bidentate carbodicarbene-rhodium complex and involve commercially available allyltrifluoroborates and an alco-hol. The reaction is applicable to vinyl arenes, and aryl or alkyl-substituted 1,3-dienes (30 examples). Allyl addition products are generated in 40–78% yield and in up to >98:2 site-selectivity. Reaction outcomes are consistent with the intermedi-acy of a Rh(III)-hydride generated by protonation of Rh(I) by an acid. A number of key mechanistic details of the reaction are presented: (1) Deuterium scrambling into the product and starting alkene indicates reversible Rh(III)–H migratory insertion. (2) A large primary kinetic isotope effect is observed. (3) With substituted allyltrifluoroborates (e.g., crotyl-BF3K) mixtures of site isomers are generated as a result of transmetalation followed by Rh-(allyl) complex equilibration; consequently, disproving outer-sphere addition of the allyl nucleophile to Rh(III)-(η3-allyl). (4) The stereochemical analysis of a cyclohexadiene allyl addition product supports a syn Rh(III)–hydride addition. (5) A Hammett plot shows a negative slope suggesting reductive elimination as the rate-determining step. Finally, utility is highlighted by a iodocyclization and cross metathesis. 

Abstract Described is a systematic comparison of factors impacting the relative rates and selectivities of C(sp³)−C and C(sp³)−O bond‐forming reactions at high‐valent Ni as a function of oxidation state. Two Ni complexes are compared: a cationic octahedral Ni^IVcomplex ligated by tris(pyrazolyl)borate and a cationic octahedral Ni^IIIcomplex ligated by tris(pyrazolyl)methane. Key features of reactivity/selectivity are revealed: 1) C(sp³)−C(sp²) bond‐forming reductive elimination occurs from both centers, but the Ni^IIIcomplex reacts up to 300‐fold faster than the Ni^IV, depending on the reaction conditions. The relative reactivity is proposed to derive from ligand dissociation kinetics, which vary as a function of oxidation state and the presence/absence of visible light. 2) Upon the addition of acetate (AcO⁻), the Ni^IVcomplex exclusively undergoes C(sp³)−OAc bond formation, while the Ni^IIIanalogue forms the C(sp³)−C(sp²) coupled product selectively. This difference is rationalized based on the electrophilicity of the respective M−C(sp³) bonds, and thus their relative reactivity towards outer‐sphere S_N2‐type bond‐forming reactions.