Synthesis and characterisation of ferrocene-containing β-diketonato complexes of rhodium(I) and rhodium(III)

The Relationship between the Electrochemical and Chemical Oxidation of Ferrocene‐Containing Carbonyl‐Phosphane‐β‐Diketonato‐Rhodium(I) Complexes – Cytotoxicity of [Rh(FcCOCHCOPh)(CO)(PPh3)]

“…0 0 [d] (0.352) [e] (79) [e] (0.321) [e] 11 [e] (1.00) [ Complexes 2-4, containing unsymmetrical β-diketonato ligands exist in solution as two isomers, see Scheme 1. [10] This equilibrium is slow to be reached, see the kinetic discussion below, and enabled us to observe each isomer by 1 H NMR separately, and to determine K c values (defined in Scheme 1) in different solvents, including CD 3 CN. [10] The CVs of 2, 3 and 4 ( Figure 2) are thus expected to exhibit two electrochemically irreversible anodic rhodium(I) oxidation peaks and two peaks that are associated with the ferrocenyl groups of the two isomers of 2, 3 and 4.…”

“…[d] The IR carbonyl stretching frequency of [Rh(β-diketonato)(CO)(PPh 3 )] complexes, see ref. [10] .…”

“…Parameters that are related to the electron density on the rhodium centre in [Rh I (β-diketonato)(CO)(PPh 3 )] is the pKЈ a value of the β-diketone RЈCOCH 2 COR coordinated to the rhodium complex (RЈ = Fc or any other group), and the group electronegativities χ RЈ or χ R of the RЈ and R side groups on the β-diketonato ligand. [10] In turn, an increase in the electron density on the Rh metal centre will result in lower CO infrared stretching frequencies, ν CO , in [Rh I (β-diketonato)-(CO)(PPh 3 )]. [10] With respect to group electronegativity sums, (χ RЈ + χ R ), and pKЈ a values, the apparent acid strength of the free β-diketones RЈCOCH 2 COR, it was shown in ref.…”

“…[9,10] They are often used in electron two separate waves, each one being associated with an isomer. Slow isomerisation kinetics allowed the detection of two isomers of 2-4.…”

Preparation of Remote NHC Complexes of Rhodium(I) and Gold(I) by Ligand Transfer

“…Crystallisation of trans-4 was not achieved -the equilibrium might shift towards the cis isomer during crystallisation. Geometric isomerism in Rh I complexes has been observed, [15] albeit related nN 2 HC 5 -analogues of 4 have only been isolated when being cis-disposed. [16] For the transfer reactions to Au I a rNHC ligand with a phenyl substituent was synthesised to avoid thermal motion associated with the alkyl chain that had been observed in the crystals of 4 (vide infra).…”