Secondary bonding. Part 13. Aryl-tellurium(IV) and -iodine(III) acetates and trifluoroacetates. The crystal and molecular structures of bis-(p-methoxyphenyl)tellurium diacetate, µ-oxo-bis[diphenyltrifluoroacetoxytellurium] hydrate, and [bis(trifluoroacetoxy)iodo]benzene

Abstract

The crystal and molecular structures of the title compounds have been determined from diffractometer data by the heavy-atom method, and their preparations are described. Crystals of (p-MeOC₆H₄)₂Te(O₂CMe)₂(1) are monoclinic, space group P2₁/c, with unit-cell dimensions a= 9.529(2), b= 11.984(2), c= 17.035(2)Å, β= 101.70(2)°, Z = 4, and for 3 033 observed reflections [I/σ(I) > 3.0], R= 0.022. Crystals of {[Ph₂Te(O₂CCF₃)]₂O}₂·H₂O (2) are triclinic, space group P, with unit-cell dimensions a= 13.988(3), b= 14.287(3), c= 15.689(3)Å, α= 80.40(2), β= 81.89(2), γ= 86.65(2)°, Z= 2, and for 5 290 observed reflections, R= 0.042. Crystals of PhI(O₂CCF₃)₂(3) are triclinic, space group P, with unit-cell dimensions a= 9.787(4), b= 9.055(3), c= 7.674(3)Å, α= 91.45(3), β= 99.78(3), γ= 89.21 (3)°, Z= 2, and for 2 104 observed reflections, R= 0.037. All three compounds have pseudo-trigonalbipyramidal primary geometry [Te–C 2.098(3) and 2.103(4), I–C 2.074(4); Te–O(µ-oxo) 1.981 (7), Te–O and I–O (oxy-anion) 2.138–2.352 Å], and form secondary bonds to give pentagonal planar systems around Te and I, also with linear C–Te ⋯ O systems. In the light of these results, previously published tellurium nitrate structures are re-interpreted.