31P CP-MAS NMR, Vibrational, and X-Ray Characterization of the Adducts of Triphenylphosphine Sulfide with ICl and IBr

The reactions between triphenylphosphine sulfide (Ph3PS) and ICl in CCl4 and IBr in CH2Cl2 in 1:1 molar ratio give the solid adducts Ph3PS · ICl (I) and Ph3PS · IBr (II) whose structures have been solved by X-ray diffraction. Compounds I and II consist of discrete molecule units and feature the S-I-Cl or S-I-Br linear group. The S-I bond distances in I, II (2.641(1), 2.665(1) Å respectively) and in compound 2 Ph3PS · 3I2 (III) (2.729(2) Å) are correlable to the net increase in the I-X (X = Cl, Br, I) bond distance. The structural features of I, II and III are in accordance with 31P CP-MAS NMR, FT-Raman and FT-IR spectral data, and elucidate the nature of the donor (Ph3PS)-acceptor (ICl, IBr, I2) interaction.