Thio derivatives of b-diketones and their metal chelates. XXII. Dipole moments of some bivalent and trivalent metal complexes of fluorinated monothio-b-diketones

Abstract

Dipole moments have been determined by static polarization measurements for some iron(111), ruthenium(111), rhodium(111), nickel(11), palladium(11), platinum(11), copper(11) and zinc(11) complexes of fluorinated monothio-β-diketones RC(SH)=CHCOCF₃. The moments indicate a facial-octahedral configuration for the iron, ruthenium and rhodium complexes, a cis-square-planar configuration for the nickel, palladium and platinum complexes, and a tetrahedral configuration for the zinc complexes. The copper complexes have moments 0.5-1.0 D lower than the mean value for the corresponding nickel, palladium and platinum complexes; this lowering of the moment is attributed to significant distortion from the square-planar towards the tetrahedral configuration. The dipole moments of the square-planar and octahedral complexes decrease if the R groups are arranged in the order: p-MeC₆H₄ ≥ 2-thienyl > β-naphthyl > m-MeC₆H₄ > Ph > Pr^? > Buⁱ > Me > m-ClC₆H₄ > m-BrC₆H₄ > p-FC₆H₄ > p-ClC₆H₄ > p-BrC₆H₄ > m,p-Cl₂C₆H₃.