Protonation of some cyclic triphosphenium ions

Several cyclic triphosphenium ions of various ring sizes have been successfully protonated to form the corresponding triphosphane di-ium dications, either by a tBuCl/AlCl3 mixture and/or by triflic acid. The latter reagent appears to be harsher, however, sometimes leading to decomposition. The new dications have been identified in solution by 31P NMR spectroscopy; recording the spectra proton coupled as well as decoupled has enabled 1JPH as well as 1JPP to be evaluated in most cases. The protonated derivatives of three compounds could not be observed, with only decomposition products being detected. In the case of the triphosphenium ion derived from bis-1,4-diphenylphosphinobutane (dppb), clear spectroscopic evidence for an intermediate in the decomposition process of the di-ium dication has been obtained, enabling a plausible mechanism to be proposed. In addition, a novel triphosphorus-containing trication with a norbornane-like structure has been detected, and characterized by single crystal X-ray diffraction, as a minor product from the protonation of the triphosphenium ion derived from cis-bis-1,2-diphenylphosphinoethene (dppE). © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:447–452, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20124

[1]  A. Goeta,et al.  1,1,3,3-Tetra­phenyl-1,2,3-triphosphenium tetra­chloro­aluminate di­chloro­methane solvate , 2005 .

[2]  A. Goeta,et al.  ‘Tennis Rackets for Octopodes’ – the crystal and molecular structure of a novel triphosphorus-containing trication , 2004 .

[3]  K. B. Dillon,et al.  The identification of some novel four‐membered ring cyclic triphosphenium ions in solution , 2004 .

[4]  K. B. Dillon,et al.  Methylation of some cyclic triphosphenium ions , 2004 .

[5]  J. Howard,et al.  Structural and 31P NMR solution studies on some cyclic triphosphenium ions and their 2‐arsa‐analogues , 2001 .

[6]  Deborah A. Longbottom,et al.  Characterization of cyclic triphosphenium ions in solution, and the crystal and molecular structure of 1,1,3,3‐tetraphenyl‐tetrahydro‐1,2,3‐triphosphenium hexachlorostannate , 2000 .

[7]  H. Karsch,et al.  Phosphinomethanides and Group 15 element halides: Redox reactions, rearrangements and novel heterocycles , 1997 .

[8]  F. Hahn,et al.  A Triphosphete and a Spirocyclic Cation with a PP4 Skeleton and a 10e Spiro P Atom , 1996 .

[9]  E. Herdtweck,et al.  A New Method for the Synthesis of Amphipolar Phosphorus‐Containing Heterocycles , 1995 .

[10]  H. Schmidbaur,et al.  Synthesis and molecular structure of heterocycles containing two phosphorus(V) centers bridged by two-coordinate phosphorus and arsenic , 1993 .

[11]  P. Gates,et al.  Solids containing methylhalophosphonium cations [(CH3)n PX+4−n] (n = 1–3 XCl,Br): an investigation using magic-angle spinning NMR spectroscopy , 1992 .

[12]  P. Gates,et al.  Solids containing tetrahalophosphonium cations : an investigation using 31P and 11B magic-angle spinning NMR and Raman spectroscopy , 1991 .

[13]  W. Sheldrick,et al.  Ein N/P‐Analogon des Cyclotetraphosphazens: Reaktionen und Struktur des Octaphenyl‐1,5,2λ5,3,4λ5,6λ5,7,8λ5‐diazahexaphosphocins und seines PdCl2‐Komplexes , 1989 .

[14]  A. Schmidpeter,et al.  Cyclische Triphosphenium-Ionen: Selektiver intramolekularer Ligandenaustausch in einer nucleophilen Substitution am zweifachkoordinierten Phosphor [1] / Cyclic Triphosphenium Ions: Selective Intramolecular Exchange of Ligand in a Nucleophilic Substitution at the Two-Coordinate Phosphorus [1] , 1985 .

[15]  W. Sheldrick,et al.  A diphos‐Complex of P⊕: The 1,1,3,3‐Tetraphenyl‐1λ5,2λ3,3λ5‐triphospholenyl Cation , 1982 .