Synthesis and characterisation of dirhodium(II) tetraacetates bearing axial ferrocene ligands

Effects of Axial Solvent Coordination to Dirhodium Complexes on the Reactivity and Selectivity in C–H Insertion Reactions: A Computational Study

“…Most reported X-ray crystal structures of dirhodium complexes contain bound axial ligands, usually solvent but sometimes substrates, other ligands, or other complexes (i.e., in coordination polymers). − Even though dirhodium complexes have been known since the 1960s, it was not until 2002 that an X-ray crystal structure of a dirhodium complex without axial ligands was reported . The few reported X-ray structures of dirhodium carbenes crystallize as coordination polymers: OMe or NMe 2 groups present in the carbene appendants coordinate to the rhodium not bearing the carbene carbon of the next unit. , These complexes require CH 2 Cl 2 and toluene to be stable in crystalline form and their unit cells contain highly disordered solvent molecules …”

Synthesis and Electrochemical Behavior of Metal Carbonyl Isocyanoferrocene Compounds [M(CO)6‐n(C≡NFc)n] (M=Cr, Mo, W; n=1, 2, 3)

“…[6,[33][34][35] It is likely that upon replacement of carbonyl ligands by stronger σ donor but weaker π acceptor isonitrile ligands the ν N�C frequencies increase, while the appropriate CO frequencies decrease, which is a consequence of the population of the π* antibonding orbitals of the CO ligands. [35f,36] Hence, complexation of C�NFc to M(CO) n fragments (n = 3, 4, 5) induces a shift of the ν N�C bands from 2125 cm À 1 (non-coordinated 2) [14,16] to ca. 2145 cm À 1 (3a-c, A 1 ), (Experimental).…”

“…[32,35] The ferrocenyl groups display for the C 5 H 5 one, and for the C 5 H 4 ligands three carbon signals at 66-81 ppm, as expected (Experimental). [13,14,16,17,23,41] The electronic properties of 2, 3 a-c, 5 and 6 were studied using cyclic (= CV) and square wave voltammetry (= SWV) as well as in situ IR spectroelectrochemistry (3 a-c) (Table 1; Figures 1 and 2; Figures SI1-SI8, see the ESI). The electrochemical measurements were performed under an atmosphere of argon in anhydrous dichloromethane solutions containing [NBu 4 ][B(C 6 F 5 ) 4 ] (0.1 mol L À 1 ) as supporting electrolyte at 25 °C.…”

“…[11,12] Hitherto, organometallic complexes with functionalized isocyanoferrocenes with a wide range of transition metals (Cr, Rh, Pd, Cu, Au, …) are known. [13][14][15][16][17][18][19][20][21][22][23] In this context, homoleptic complexes of type [Cr(C�NFc) 6 ] and [Cr(C�NFc) 6 ] n + (n = 1, 2; Fc=Fe(η 5 À C 5 H 4 )(η 5 À C 5 H 5 )), [19,20I] as well as barely characterized metal carbonyl isocyanoferrocenes [M(CO) 6-n (C�NFc) n ] (M=Cr, n = 1; M=Mo; n = 2), [18,21] [Fe(η 5 À C 5 H 4 N�CÀ Cr(CO) 5 ) 2 ] [22] and [Cr-(CO) 5 (C�NCHRFc)] (R=Me, i Pr, t Bu, c Hex) [18] exist. The electrochemical investigations are limited to a few of these complexes and were performed with [PF 6 ] À or [BF 4 ] À ions as supporting electrolyte.…”

Ferrocene-Bearing Homoleptic and Heteroleptic Paddlewheel-Type Dirhodium Complexes

“…Paddlewheel-type dinuclear (M 2 ) complexes, which have metal-metal bonds or interactions, have long been known as versatile building blocks that can rationally coordinate Inorganics 2024, 12, 41 2 of 14 organic ligands or metalloligands at the equatorial positions of the M 2 cores [18]. Fcabearing paddlewheel-type M 2 complexes have been investigated for several M 2 cores, such as Cu, Zn, Mo, Ru, and Rh [19][20][21][22][23][24][25][26][27][28]. For example, Churchill reported the crystal structure of [Cu 2 (fca) 4 (THF) 2 ], in which four fca and two THF ligands are coordinated to the equatorial and axial positions, respectively, of a Cu 2 core, and four ferrocene units adopt both eclipsed and staggered conformations in a 2:2 ratio [19].…”