Tertiary Phosphine and Arsine Complexes of Phosphorus Pentafluoride: Synthesis, Properties, and Electronic Structures.

The reaction of PMe3 or PPh3 with PF5 in anhydrous CH2Cl2 or hexane forms the white, moisture-sensitive complexes [PF5(PR3)] (R = Me, Ph). Similar reactions involving the diphosphines o-C6H4(PR2)2 afford the complexes [PF4{o-C6H4(PR2)2}][PF6]. The X-ray structures of [PF5(PR3)] and [PF4{o-C6H4(PMe2)2}][PF6] show pseudo-octahedral fluorophosphorus centers. Multinuclear NMR spectra (1H, 19F{1H}, 31P{1H}) show that in solution in CH2Cl2/CD2Cl2 the structures determined crystallographically are the only species present for [PF5(PMe3)] and [PF4{o-C6H4(PMe2)2}][PF6] but that [PF5(PPh3)] and [PF4{o-C6H4(PPh2)2}][PF6] exhibit reversible dissociation of the phosphine at ambient temperatures, although exchange slows at low temperatures. The complex 19F{1H} and 31P{1H} NMR spectra have been analyzed, including those of the cation [PF4{o-C6H4(PMe2)2}]+, which is a second-order AA'XX'B2M spin system. The unstable [PF5(AsMe3)], which decomposes in a few hours at ambient temperatures, has also been isolated and spectroscopically characterized; neither AsPh3 nor SbEt3 forms similar complexes. The electronic structures of the PF5 complexes have been explored by DFT calculations. The DFT optimized geometries for [PF5(PMe3)], [PF5(PPh3)], and [PF4{o-C6H4(PMe2)2}]+ are in good agreement with their respective crystal structure geometries. DFT calculations on the PF5-L complexes reveal the P-L bond strength falls with L in the order PMe3 > PPh3 > AsMe3, consistent with the experimentally observed stabilities, and in the PF5-L complexes, electron transfer from L to PF5 on forming these complexes also follows the order PMe3 > PPh3 ≈ AsMe3.

[1]  W. Levason,et al.  Coordination chemistry and applications of medium/high oxidation state metal and non-metal fluoride and oxide-fluoride complexes with neutral donor ligands , 2019, Coordination Chemistry Reviews.

[2]  W. Levason,et al.  Trialkylstibine Complexes of Boron, Aluminum, Gallium, and Indium Trihalides: Synthesis, Properties, and Bonding , 2018, Organometallics.

[3]  W. Levason,et al.  Systematics of BX3 and BX2(+) Complexes (X = F, Cl, Br, I) with Neutral Diphosphine and Diarsine Ligands. , 2016, Inorganic chemistry.

[4]  Michael J. Rose,et al.  Antimony-Supported Cu4I4 Cuboid with Short Cu-Cu Bonds: Structural Premise for Near-Infrared Thermoluminescence. , 2016, Inorganic chemistry.

[5]  A. Hector,et al.  Complexes of aluminium, gallium and indium trifluorides with neutral oxygen donor ligands: Synthesis, properties and reactions , 2016 .

[6]  W. Levason,et al.  Six-coordinate NbF5 and TaF5 complexes with tertiary mono-phosphine and -arsine ligands , 2015 .

[7]  G. Röschenthaler,et al.  Highly reactive carbenes as ligands for main group element fluorides. Syntheses and applications , 2015 .

[8]  C. Tian,et al.  C- and N-Adducts of N-alkenyl substituted Arduengo carbene and N-alkyl substituted imidazole with PF5: synthesis and structural investigation , 2014, Russian Chemical Bulletin.

[9]  W. Levason,et al.  Coordination chemistry of the main group elements with phosphine, arsine and stibine ligands , 2014 .

[10]  G. Röschenthaler,et al.  Carbene Complexes of Phosphorus(V) Fluorides by Oxidative Addition of 2,2-Difluorobis(dialkylamines) to Phosphorus(III) Halides , 2012 .

[11]  W. Nie,et al.  High-Yield Thermolytic Conversion of Imidazolium Salts into Arduengo Carbene Adducts with BF3 and PF5 , 2012 .

[12]  Stefan Grimme,et al.  Effect of the damping function in dispersion corrected density functional theory , 2011, J. Comput. Chem..

[13]  A. Hector,et al.  Hypervalent neutral O-donor ligand complexes of silicon tetrafluoride, comparisons with other group 14 tetrafluorides and a search for soft donor ligand complexes. , 2011, Dalton transactions.

[14]  W. Levason,et al.  Complexes of germanium(IV) fluoride with phosphane ligands: structural and spectroscopic authentication of germanium(IV) phosphane complexes. , 2008, Dalton transactions.

[15]  Stefan Grimme,et al.  Semiempirical GGA‐type density functional constructed with a long‐range dispersion correction , 2006, J. Comput. Chem..

[16]  W. Levason,et al.  Tin(IV) Fluoride Complexes with Tertiary Phosphane Ligands – A Comparison of Hard and Soft Donor Ligands , 2006 .

[17]  G. Müller,et al.  Donor-Acceptor Complexes between Simple Phosphines. First Structural Data for an Almost Forgotten Class of Compounds , 2001 .

[18]  W. Marshall,et al.  Carbene Complexes of Pnictogen Pentafluorides and Boron Trifluoride , 2000 .

[19]  W. Marshall,et al.  A Carbene−Phosphorus(V) Adduct , 1997 .

[20]  G. Bertrand,et al.  From 1σ4, 2σ2 to 1σ4, 2σn‐Diphosphetes (n = 3–6): The Surprising Persistence of the PP bond , 1996 .

[21]  M. Frisch,et al.  Ab Initio Calculation of Vibrational Absorption and Circular Dichroism Spectra Using Density Functional Force Fields , 1994 .

[22]  Emilia Sicilia,et al.  Graphical Interactive Strategy for the Analysis of NMR Spectra in Liquid Crystalline Phases , 1994, J. Chem. Inf. Comput. Sci..

[23]  A. Becke Density-functional thermochemistry. III. The role of exact exchange , 1993 .

[24]  Fanqi Qu,et al.  Preparation and NMR spectra of PF4(N-N)+ and SiF4(N-N), where N-N = 2,2′-bipyridine, 4-fluoro-2,2′-bipyridine, and 1,10-phenanthroline , 1992 .

[25]  M. Wiebcke,et al.  Fluorides and fluoro acids. XIII. The crystal structure of phosphorus pentafluoride , 1987 .

[26]  Ronald L. Harris,et al.  A facile synthesis of 1,2-bis(phosphino)benzene and related alkylated species , 1983 .

[27]  G. Röschenthaler,et al.  The Crystal Molecular Structure of the Adduct of 2,2,2-Trifluoro-4,4,5,5-tetrakis(trifluoromethyl)-l,3,2A 5 -dioxaphospholane with Trimethylphosphine. A Strong P → P Coordinate Bond , 1978 .

[28]  R. Schmutzler,et al.  Chemie der Phosphorfluoride, XXXVII / Phosphorus-Fluorine Chemistry, XXXVII , 1974 .

[29]  C. Schultz,et al.  Phosphorus-phosphorus bond. I. Complexes containing highly connected phosphorus atoms, HnMe3-nPPF5. Directly bonded phosphorus-phosphorus coupling constant , 1971 .

[30]  P. Treichel,et al.  The Thermal Rearrangement of Phosphorus Pentafluoride Adducts of Dimethyl Ether and Dimethyl Sulfide , 1966 .

[31]  L. Bartell,et al.  Electron Diffraction Study of the Structure of PF5 , 1965 .

[32]  M. Winter,et al.  Carbene Adduct as Overcharge Protecting Agent in Lithium Ion Batteries , 2012 .

[33]  D. Philp,et al.  Use of Molecular Scaffolding for the Stabilization of an Intramolecular Dative PIII-PV System , 2003 .

[34]  T. O'donnell Chapter 11 – Superacidic Reaction Media , 2000 .

[35]  A. Heyns The i.r. and Raman spectra of sodium hexafluorophosphate monohydrate, NaPF6·H2O , 1977 .

[36]  D. Sharp,et al.  Reactions between phosphorus pentafluoride and methylamine, ethylamine, and t-butylamine , 1970 .

[37]  D. H. Brown,et al.  Reactions between phosphorus fluorides and trialkylphosphines and aminophosphines , 1969 .

[38]  E. Muetterties,et al.  Autoionization in complexes of metal pentafluorides , 1967 .