Fluoride Ion Donor Properties of TcO₂F₃and ReO₂F₃:  X-ray Crystal Structures of MO₂F₃·SbF₅(M = Tc, Re) and TcO₂F₃·XeO₂F₂and Raman and NMR Spectroscopic Characterization of MO₂F₃·PnF₅(Pn = As, Sb), [ReO₂F₂(CH₃CN)₂][SbF₆], and [Re₂O₄F₅][Sb₂F₁₁]

Abstract

The fluoride ion donor properties of TcO2F3 and ReO2F3 toward AsF5, SbF5, and XeO2F2 have been investigated, leading to the formation of TcO2F3.PnF5 and ReO2F3.PnF5 (Pn = As, Sb) and TcO2F3.XeO2F2, which were characterized in the solid state by Raman spectroscopy and X-ray crystallography. TcO2F3.SbF5 crystallizes in the monoclinic system P2(1)/n, with a = 7.366(2) A, b = 10.441(2) A, c = 9.398(2) A, beta = 93.32(3) degrees, V = 721.6(3) A3, and Z = 4 at 24 degrees C, R1 = 0.0649, and wR2 = 0.1112. ReO2F3.SbF5 crystallizes in the monoclinic system P2(1)/c, with a = 5.479(1) A, b = 10.040(2) A, c = 12.426(2) A, beta = 99.01(3) degrees, V = 675.1(2) A3, and Z = 4 at -50 degrees C, R1 = 0.0533, and wR2 = 0.1158. TcO2F3.XeO2F2 crystallizes in the orthorhombic system Cmc2(1), with a = 7.895(2) A, b = 16.204(3) A, c = 5.198(1) A, beta = 90 degrees, V = 665.0(2) A3, and Z = 4 at 24 degrees C, R1 = 0.0402, and wR2 = 0.0822. The structures of TcO2F3.SbF5 and ReO2F3.SbF5 consist of infinite chains of alternating MO2F4 and SbF6 units in which the bridging fluorine atoms on the antimony are trans to each other. The structure of TcO2F3.XeO2F2 comprises two distinct fluorine-bridged chains, one of TcO2F3 and the other of XeO2F2 bridged by long Tc-F...Xe contacts. The oxygen atoms of the group 7 metals in the three structures are cis to each other and to two terminal fluorine atoms and trans to the bridging fluorine atoms. The 19F NMR and Raman spectra of TcO2F3.PnF5 and ReO2F3.PnF5 in SbF5 and PnF5-acidified HF solvents are consistent with dissociation of the adducts into cis-MO2F2(HF)2+ cations and PnF6- anions. The energy-minimized geometries of the free MO2F2+ cations and their HF adducts, cis-MO2F2(HF)2+, have been calculated by local density functional theory (LDFT), and the calculated vibrational frequencies have been used as an aid in the assignment of the Raman spectra of the solid MO2F3.PnF5 adducts and their PnF5-acidified HF solutions. In contrast, ReO2F3.SbF5 ionizes in SO2ClF solvent to give the novel Re2O4F5+ cation and Sb2F11- anion. The 19F NMR spectrum of the cation is consistent with two ReO2F2 units joined by a fluorine bridge in which the oxygen atoms are assumed to lie in the equatorial plane. The [ReO2F2(CH3CN)2][SbF6] salt was formed upon dissolution of ReO2F3.SbF5 in CH3CN and was characterized by 1H, 13C, and 19F NMR and Raman spectroscopies. The ReO2F2(CH3CN)2+ cation is a pseudooctahedral cis-dioxo arrangement in which the CH3CN ligands are trans to the oxygens and the fluorines are trans to each other.

Experimental and Theoretical Characterization of Cationic, Neutral, and Anionic Binary Arsenic and Antimony Azide Species

“…The As(N 3 ) 4 + cation could not be detected in the 75 As NMR spectra since, due to the large quadrupole moment of 75 As, this nucleus can only be detected in a very symmetrical environment . The first tetrahedrally coordinated arsenic halogen compounds characterized by 75 As NMR spectroscopy were the AsCl 4 + and the AsBr 4 + cations recently published by Schrobilgen et al The 19 F NMR spectrum of [Sb(N 3 ) 4 ][Sb 2 F 11 ] in SO 2 consists of three multiplet resonances at δ −90.5, −98.4, and −128.7, indicating the presence of Sb 2 F 11 - anions . Similar with [As(N 3 ) 4 ][AsF 6 ], other signals indicative of partial or complete azide−fluoride exchange in the anion could not be detected.…”

X-ray Crystal Structures of α-KrF2, [KrF][MF6] (M = As, Sb, Bi), [Kr2F3][SbF6]·KrF2, [Kr2F3]2[SbF6]2·KrF2, and [Kr2F3][AsF6]·[KrF][AsF6]; Synthesis and Characterization of [Kr2F3][PF6]·nKrF2; and Theoretical Studies of KrF2, KrF+, Kr2F3Lehmann1, Dixon2, Schrobilgen3 2001Inorg. Chem.Self Cite77191150View full textAdd to dashboardCite

“…Fluorine gas (Air Products) was used without further purification. Antimony pentafluoride was synthesized in situ by direct fluorination of SbF 3 with F 2 in anhydrous HF as previously described …”

The OsO3F+ and μ-F(OsO3F)2+ Cations: Their Syntheses and Study by Raman and 19F NMR Spectroscopy and Electron Structure Calculations and X-ray Crystal Structures of [OsO3F][PnF6] (Pn = As, Sb), [OsO3F][HF]2[AsF6], [OsO3F][HF][SbF6], and [OsO3F][Sb3F16]

“…The starting compounds, OsO 3 F 2 , AsF 5 , SbF 5 , and SbF 3 , were prepared by standard literature methods. Sulfuryl chloride fluoride, SO 2 ClF (Aldrich), was purified by the standard literature methods and stored over anhydrous KF.…”