Complexes of d(+)-biotin with Pd(II) and Pt(II)

The reactions of d(+)-biotin with K₂MX₄, where M = Pd(II) or Pt(II) and X = Cl or Br have been studied in acidic, neutral or alkaline aqueous solutions. Complexes of the type trans-M(Bio)₂X₂ have been isolated for both metals and characterized with elemental analyses, conductivity measurments, ir spectra, ¹Hnmr and ¹³Cnmr spectra. The complex of the type Pd(Bio)Cl₂]₂ has also been isolated from DMF solutions. The results indicate that d(+)-biotin coordinates exclusively through its sulfur atom with these metals in all the complexes in the present study, in the solid state or in solution.