Reactions of antimony triiodide with methoxymethyltriphenylphosphonium iodide

Abstract

The interaction of methoxymethyltriphenylphosphonium iodide with antimony triiodide in acetone yielded ionic complexes [CH3OCH2PPh3]4[Sb4I12] ∙ 2Me2C=O (1) (equimolar ratio of the initial reagents) and [CH3OCH2PPh3]4[Sb6I22] ∙ 2SbI3 (2) (molar ratio of the initial reagents equaled 1:2), the structure of which was established by X-ray structural analysis. According to the X-ray diffraction data carried out at 100 K on a D8 Quest Bruker automatic four-circle diffractometer (two-coordinate CCD detector, MoKα radiation, λ = 0.71073 Å, graphite monochromator), in crystals 1 [C86H92O6P4I16Sb4, M 862.88; triclinic syngony, symmetry group P–1; cell parameters: a = 13.458(3), b = 15.257(4), c = 16.324(6) Å; α = 88.745(15)°, β = 66.951(18)°, γ = 70.314(11)°; V = 2880.6(14) Å3; crystal size 0.33×0.2×0.16 mm; reflection index ranges -21 ≤ h ≤ 21, -23 ≤ k ≤ 23, -25 ≤ l ≤ 25; total reflections 159270; independent reflections 22913; Rint 0.0384; GOOF 1.027; R1 = 0.0386, wR2 = 0.0841; residual electron density 1.44/-1.83 e/Å3], 2 [C80H80I28O4P4Sb8, M 5756.60; triclinic syngony, symmetry group P–1; cell parameters: a = 10,7689(3), b = 16,6284(5), c = 18,9863(5) Å; α = 96,613(2)°, β = 98,276(2)°, γ = 100,607(2)°; V = 3271,71(16) Å3; crystal size 0,29×0,18×0,12 mm; reflection index intervals -13 ≤ h ≤ 13, -21 ≤ k ≤ 21, -24 ≤ l ≤ 24; total reflections 38234; independent reflections 14993; Rint 0,0258; GOOF 1.052; R1 = 0.0229, wR2 = 0.0418; residual electron density 1.33/-1.32 e/Å3] the phosphorus atoms in cations have a slightly distorted tetrahedral coordination with the CPC angles of 105.37(18)-111.24(18)°, 105.38(16)-114.29(16)° and the P-C bond lengths of 1.783(4)-1.825(4) Å, 1.772(4)-1.814(3) Å in 1 and 2, respectively. In the [Sb4I16]4- and [Sb6I22]4- anions, the antimony atoms have a distorted octahedral coordination (trans-angles 169.170(12)–176.299(12)° and 168.158(10)–176.794(10)°. The Sb–Ibridge bonds (2.9203(6)-2.3461(6) Å and 2.8608(4)-3.4052(8) Å) are longer than the terminal Sb–Iterm bonds (2.8176(8)-2.9179(8) Å and 2.7653(4)-2.8015(3) Å). In the terminal SbI3 groups in 2 the antimony atoms Sb(3) have the coordination of a trigonal bipyramid, in the equatorial positions of which, along with two iodine atoms [I(2) and I(3)], there is a lone electron pair. The axial positions are occupied by I(4) [the I(4)-Sb(4) distance is 2.7798(3) Å] and the iodine atom I(10) of the [Sb6I22]4- anion [the I(10)∙∙∙Sb(4) distance is 3.4310(3) Å]. Complete tables of atomic coordinates, bond lengths, and valence angles for the structures have been deposited with the Cambridge Crystallographic Data Centre (No. 2224162 (1), No. 2362613 (2); deposit@ccdc.cam.ac.uk; https://www.ccdc.cam.ac.uk).