ALKYL- UND ARYL-KOMPLEXE DES IRIDIUMS UND RHODIUMS. X. CHELATPHOSPHIN-STABILISIERTE RHODIUMORGANYLE Rh(R)(PhP(CH2CH2CH2PPh2)2): SYNTHESE, NMR-SREKTROSKOPISCHER cis,trans-EINFLUSS UND MOLEKUELSTRUKTUR VON Rh(2-MeC6H4)

Article abstract of DOI:10.1016/0022-328X(83)80022-9

The organorhodium(I) complexes Rh(R) (R = CH2CMe3, CH2SiMe3; 2-MeC6H4, 4-MeC6H4, 2,4-Me2C6H3, 2,4,6-Me3C6H2; C2Ph) have been prepared and characterized by 31P and 1H NMR spectroscopy and an X-ray structure determination of the tolyl derivative Rh(2-MeC6H4).For these compounds, the relative 31P coordination shifts Δ(PPh2) > Δ(PPh) distinctly reflect the electron-releasing properties of the organoligands ?-bonded trans to PPh.As expected, coupling between the 103Rh nucleus and the phenylphosphino P atoms is weak and varies only little as the strong trans influence groups R are changed.In contrast to this insensitivity of ¹J(Rh-PPh) to R, Rh-P coupling within the Ph2P-Rh-PPh2 moieties shows considerable dependence upon the nature of the C-donor producing the cis influence series sp³-C < sp²-C < sp-C.The ortho-tolyl complex crystallizes from toluene as 1/1 solvate Rh(2-MeC6H4) * C7H8.Crystals are orthorhombic, space group Pbc2₁, with a 1017.9(7), b 1974.3(14), c 2177.6(11) pm, and Z = 4.The structure has been refined to R = 0.079 for 2249 unique data with F₀ > 3?(F₀).Metal-phosphorus distances are 225.7(5) and 229.6(6) pm for Rh-PPh2 and 227.3(6) pm for Rh-PPh.