For in vivo determination of optically active (chiral) substances in turbid media, like for example glucose in human tissue, the backscattering geometry is particularly convenient. However, recent polarimetric measurements performed in the backscattering geometry have shown that, in this geometry, the relatively small rotation of the polarization vector arising due to the optical activity of the medium is totally swamped by the much larger changes in the orientation angle of the polarization vector due to scattering. We show that the change in the orientation angle of the polarization vector arises due to the combined effect of linear diattenuation and linear retardance of light scattered at large angles and can be decoupled from the pure optical rotation component using polar decomposition of Mueller matrix. For this purpose, the method developed earlier for polar decomposition of Mueller matrix was extended to incorporate optical rotation in the medium. The validity of this approach for accurate determination of the degree of optical rotation using the Mueller matrix measured from the medium in both forward and backscattering geometry was tested by conducting studies on chiral turbid samples prepared using known concentration of scatterers and glucose molecules.

The reaction of py2Te2 or (3‐MeC5H3N)2Te2 with Na2PdCl4 in methanol yields an insoluble brown complex, [PdCl(TeNC5H3R)]n (R = H or Me). Several reactions of pyTe−, (3‐MeC5H3N)Te−, or (6‐MeC5H3N)Te− with various palladium(II) and platinum(II) complexes have been carried out. Complexes of the types [MCl(Te−N)(PR3)], [Pt(Te−N)2(dppe)], [Pt(Te−N)2(PPh3)2], and [Pt2(μ‐Te−N)2(dppe)2][BPh4]2 [M = Pd or Pt; Te−N = pyTe, (3‐ or 6‐MeC5H3N)Te] have been prepared and characterized by elemental analyses, UV/Vis, IR, and NMR (1H, 31P, 195Pt) spectroscopy. The complexes [MCl(Te−N)(PR3)] show irreversible oxidation and reduction by CV in DMF. The molecular structure of [PdCl{Te(3‐MeC5H3N)}(PPh3)] (2c) has been established by single‐crystal X‐ray diffraction analysis. The palladium atom is bound to the chelating 3‐methylpyridinetellurolate ligand, a chlorine atom and a PPh3 ligand. The pyrolysis of [PdCl{Te(3‐MeC5H3N)}(PR3)] (PR3 = PEt3 or PPh3) at 340 °C yields PdTe. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

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