The impact of multi-NMR spectroscopy on the development of noble-gas chemistry

doi:10.1016/S0010-8545(99)00188-5

Coordination Chemistry Reviews

Volume 197, Issue 1, February 2000, Pages 335-395

https://doi.org/10.1016/S0010-8545(99)00188-5 Get rights and content

Abstract

The role of nuclear magnetic resonance spectroscopy in the structural studies of xenon and krypton species has been essential to the development of noble-gas chemistry since the early ¹⁹F-NMR studies carried out in Ronald J. Gillespie's laboratory at McMaster University in the late 1960's and early 1970's. These early investigations of noble-gas species in strong acid media and subsequent multi-nuclear magnetic resonance (multi-NMR) studies utilizing ¹H, ¹³C, ¹⁴N, ¹⁵N, ¹⁷O, ⁷⁷Se, ¹²⁵Te, ¹²⁹Xe, and ¹³¹Xe as the observed nuclides have made possible numerous important advances of noble-gas chemistry, contributing to our knowledge and understanding of the fluoride ion donor–acceptor behavior of noble-gas fluorides and oxide fluorides, Lewis acid properties of noble-gas species and the structures of compounds containing novel XeC, XeN, XeO, KrN, and KrO bonds. Trends among NMR parameters have also proven useful in assessing the formal oxidation state of xenon and the relative covalent characters of noble gas–ligand bonds.

Introduction

The intense interest in the preparative and structural main-group chemistry and in superacidic solvent media in Professor Ronald J. Gillespie's laboratory during the late 1960s and early to mid-1970s, provided the research background that led to the syntheses and characterization of a significant number of novel noble-gas species in his laboratory at that time. A significant driving force behind the syntheses of new noble-gas species at McMaster University lay in the desire to confirm their geometries based on the valence shell electron repulsion (VSEPR) rules. This interest was expressed shortly after the discovery of noble-gas reactivity by Neil Bartlett [1], when Ron Gillespie [2] applied the VSEPR rules to the prediction of the molecular geometries of then known and unknown xenon fluorides and oxide fluorides. Conditional on acceptance of an offer to join the McMaster Chemistry Department in 1958 from University College, London, where he was a Lecturer, Ron Gillespie had stipulated that a commercial NMR spectrometer capable of running ¹⁹F and ¹H spectra be purchased for his use at McMaster. The instrument, a Varian HR-60, operating at 56.4 MHz for ¹⁹F, and equipped with a ‘hot-wire’ plotter, was one of the first commercial NMR spectrometers in Canada and was installed during the summer of 1959. While being installed in the basement of the McMaster Engineering Building, the 2-ton electromagnet was dropped outside the building, creating a sizable indentation in the concrete pavement. Despite its early trauma, the instrument performed to specifications until 1967 when it was upgraded to a Varian DP-60 with flux stabilization, and was used by G.J. Schrobilgen, a graduate student in Ron Gillespie's group, for early ¹⁹F-NMR studies of noble-gas species from 1971–1973. The instrument was finally decommissioned in 1978. Almost simultaneous with the arrival of the Chemistry Department's first NMR spectrometer, Ron Gillespie offered the first NMR course at McMaster in the fall of 1959 and continued to do so in subsequent years. His early dedication to the use of ¹⁹F-NMR spectroscopy for the characterization of fluoro-species in superacids provided a ready-made means for the structural characterization of noble-gas species and, in particular, noble-gas fluoride and oxide fluoride cations in strong acid media.

Following on these early studies, and with the availability of commercial multi-NMR spectrometers, multi-NMR spectroscopy became an extremely powerful tool in the structural characterization of xenon and krypton species in solution and remains so today. The material treated in this review is concerned with the application and impact of NMR spectroscopy on the development of noble-gas chemistry and mainly chronicles the early research performed in Professor R.J. Gillespie's laboratory and the continuing work in the field at McMaster University by his former Ph.D. student, Professor G.J. Schrobilgen. All multi-NMR spectroscopic data cited in this review are summarized in a comprehensive table at the end of this review (Table 2).

Besides the indisputable importance of the ¹²⁹Xe nucleus for NMR spectroscopic characterization of xenon species, the role of other nuclei, e.g. ¹⁹F, ¹⁷O, ¹⁵N, ¹⁴N, ¹³C, and ¹H, in the elucidation of the solution structures of noble-gas species needs to be emphasized. Among these nuclei, ¹⁹F is by far the most important since the majority of noble-gas species are derived from fluorides or oxide fluorides. Before the widespread availability of commercial FT multi-NMR spectrometers, ¹⁹F, because of its high receptivity¹, was the only nucleus available for the routine characterization of xenon fluorides and oxide fluorides on CW instruments. The NMR spectroscopic study of krypton species is limited to the observation of NMR-active nuclei of atoms directly or indirectly attached to the krypton center, since ⁸³Kr, the only spin-active Kr nuclide, is quadrupolar and exhibits fast relaxation in asymmetric environments found in all currently known chemically bound krypton species. Hence, ¹⁹F-NMR spectroscopy is usually the only practical means to characterize krypton species in solution.

The following comprehensive reviews of ¹²⁹Xe-NMR spectroscopy should also be consulted: ‘NMR and the Periodic Table’ in the chapter by Schrobilgen [3], ‘Multinuclear NMR’ in the chapter by Jameson [4], ‘The Encyclopedia of Nuclear Magnetic Resonance’ in the chapter by Schrobilgen [5] and ‘Annual Reports on NMR Spectroscopy’ in the chapter by Ratcliffe [6], and cover the field up to and not inclusive of the years 1979, 1987, 1996, and 1998, respectively. ¹⁹F-NMR spectroscopy of noble-gas species is covered in ‘¹⁹F-NMR-Spektroskopie’, volume 4 of the series ‘NMR-Spektroskopie von Nichtmetallen’ by Berger, Braun, and Kalinowski [7], up to 1993 inclusively. The chemistry of compounds containing Xe^IIN bonds, including aspects of their characterization by multi-NMR spectroscopy, has been reviewed in ‘Synthetic Fluorine Chemistry’ in the chapter by Schrobilgen [8].

Section snippets

Early NMR studies of noble-gas species

In the late 1960's, noble-gas chemistry, especially the solution chemistry of Xe^II species in acid media, became a new focus of research in Ron Gillespie's laboratory at McMaster University. The method of choice for the characterization of solutions containing neutral xenon(II) species and xenon(II) cations generated and stabilized in strong acid solutions was ¹⁹F-NMR spectroscopy, which had not, up until that time, been extensively exploited for the study of noble-gas species in solution. The

Xenon(II) species

The earliest solution ¹⁹F-NMR studies of noble-gas compounds at McMaster University dealt with the solvolytic behaviors of XeF₂, FXeSO₃F, and Xe(SO₃F)₂ in anhydrous HF and HSO₃F solvents [16] (, , , ). The X-ray crystal structure $XeF_{2} + HSO_{3} F → HSO_{3} F FXeSO_{3} F + HF$ $FXeSO_{3} F + HSO_{3} F → HSO_{3} F Xe (SO_{3} F)_{2} + HF$ $Xe (SO_{3} F)_{2} + HF → HF FXeSO_{3} F + HSO_{3} F$ $FXeSO_{3} F + HF ⇌ HF XeF_{2} + HSO_{3} F$ of FXeSO₃F had been previously determined and was found to be a covalent molecule with a linear FXeO bonding arrangement, consistent with an AX₂E₃ VSEPR

Theoretical considerations

Theoretical approximations have been developed to represent the shielding of a nucleus such as ¹²⁹Xe by the local terms, σ^d_Xe and σ^p_Xe, which are calculated by Ramsey's theory applied to the electrons on Xe only [104]. Ramsey [105] used second-order perturbation theory to express the nuclear magnetic shielding as a sum of the first-order term, the diamagnetic term σ^d, which is analogous to the Lamb formula for an isolated atom or ion, and a second-order term, the paramagnetic term σ^p. Because

Theoretical considerations

Relativistic calculations by Pyykkö and Wiesenfeld [114] on selected nuclei revealed that the relativistic term corresponding to the nonrelativistic Fermi contact term almost invariably dominates one-bond spin–spin coupling and concur with the molecular orbital treatment of spin coupling constants by Pople and Santry [115]. The only exceptions found are the coupling constants between two group VI or group VII atoms such as SeSe or II. The Fermi contact term is generally given by Eq. (51) [116]

Isotopic shifts

The secondary effects of krypton isotopes on the nuclear shielding of ¹⁹F have been reported for three krypton compounds, ¹Δ¹⁹F(^m′/mKr)=−0.0105 ppm u⁻¹ for KrF₂ [89], −0.0138 ppm u⁻¹ for FKrNCH⁺ [88], and −0.0105 ppm u⁻¹ for FKrNCCF₃⁺ [83]. Since krypton does not have an observable spin-active nucleus exhibiting spin–spin coupling to ¹⁹F, the observation of the secondary krypton isotope shift is an important tool in unambiguously establishing the existence of a KrF bond. The only secondary

Acknowledgements

The authors thank the Canada Council for a Killam Research Fellowship (G.J.S.) and the Natural Sciences and Engineering Research Council of Canada for past and continuing support of this work in the form of research and equipment grants.

References (125)

C.I. Ratcliffe
Annu. Rep. NMR Spectrosc.
(1998)
B. Cohen et al.
J. Inorg. Nucl. Chem.
(1966)
H.D. Frame
Chem. Phys. Lett.
(1969)
F.Q. Roberto
Inorg. Nucl. Chem. Lett.
(1972)
K.O. Christe
Inorg. Nucl. Chem. Lett.
(1972)
A.L. Allred
J. Inorg. Nucl. Chem.
(1961)
F. Sladky et al.
Inorg. Nucl. Chem. Lett.
(1972)
N. Bartlett, Proc. Chem. Soc. (1962)...
R.J. Gillespie
G.J. Schrobilgen

C.J. Jameson

G.J Schrobilgen

S. Braun et al.

(1994)

G.J. Schrobilgen

J.C. Hindman et al.

T.H. Brown et al.

J. Chem. Phys.

(1963)

A.J. Edwards, J.H. Holloway, R.D. Peacock, Proc. Chem. Soc. (1963)...

V.M. McRae, R.D. Peacock, D.R. Russel, J. Chem. Soc. Chem. Commun. (1969)...

R.J. Gillespie et al.

Inorg. Chem.

(1974)

R.J. Gillespie et al.

Inorg. Chem.

(1974)

R.J. Gillespie et al.

The VSEPR Model of Molecular Geometry

(1991)

N. Bartlett, M. Wechsberg, F.O. Sladky, P.A. Bulliner, G.R. Jones, R.D. Burbank, J. Chem. Soc. Chem. Commun. (1969)...

N. Bartlett et al.

Inorg. Chem.

(1972)

F.O. Sladky, P.A. Bulliner, N. Bartlett, B.G. DeBoer, A. Zalkin, J. Chem. Soc. Chem. Commun. (1968)...

N. Bartlett et al.

Inorg. Chem.

(1974)

R.J. Gillespie et al.

Inorg. Chem.

(1974)

M. Wechsberg et al.

Inorg. Chem.

(1972)

R.J. Gillespie, G.J. Schrobilgen, D.R. Slim, J. Chem. Soc. Dalton Trans. (1977)...

N. Bartlett, F. Einstein, D.F. Stewart, J. Trotter, J. Chem. Soc. Chem. Commun. (1966)...

N. Bartlett, F. Einstein, D.F. Stewart, J. Trotter, J. Chem. Soc. A (1967)...

N. Bartlett et al.

Inorg. Chem.

(1973)

K. Leary et al.

Inorg. Chem.

(1973)

R.J. Gillespie et al.

Inorg. Chem.

(1974)

D.D. DesMarteau et al.

Inorg. Chem.

(1972)

R.J. Gillespie, B. Landa, G.J. Schrobilgen, J. Chem. Soc. Chem. Commun. (1971)...

R.J. Gillespie et al.

Inorg. Chem.

(1974)

P. Boldrini et al.

Inorg. Chem.

(1974)

D.E. McKee, C.J. Adams, A. Zalkin, N. Bartlett, J. Chem. Soc. Chem. Commun. (1973)...

D.E. McKee et al.

Inorg. Chem.

(1973)

R.J. Gillespie, B. Landa, G.J. Schrobilgen, J. Chem. Soc. Chem. Commun. (1972)...

H.P.A. Mercier et al.

Inorg. Chem.

(1993)

N. Bartlett et al.

A.G. Sharpe

F. Schreiner et al.

J. Am. Chem. Soc.

(1965)

R.J. Gillespie, G.J. Schrobilgen, J. Chem. Soc. Chem. Commun. (1974)...

R.J. Gillespie et al.

Inorg. Chem.

(1976)

K.O. Christe

Inorg. Chem.

(1973)

K.O. Christe et al.

Inorg. Chem.

(1967)

R.J. Gillespie et al.

Inorg. Chem.

(1974)

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^☆: Dedicated to Professor Ronald J. Gillespie, on the occasion of his 75th birthday and in appreciation of the exemplary high standards in basic research and scholarship he has provided us with over the years.

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The impact of multi-NMR spectroscopy on the development of noble-gas chemistry☆

Abstract

Introduction

Section snippets

Early NMR studies of noble-gas species

Xenon(II) species

Theoretical considerations

Theoretical considerations

Isotopic shifts

Acknowledgements

Annu. Rep. NMR Spectrosc.

J. Inorg. Nucl. Chem.

Chem. Phys. Lett.

Inorg. Nucl. Chem. Lett.

Inorg. Nucl. Chem. Lett.

J. Inorg. Nucl. Chem.

Inorg. Nucl. Chem. Lett.

J. Chem. Phys.

Inorg. Chem.

Inorg. Chem.

The VSEPR Model of Molecular Geometry

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

J. Am. Chem. Soc.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.

Inorg. Chem.