Skip to main content
Article
The Crystal Structures of (p-ClPh)3PO and (p-OMePh)3PO, Including an Analysis of the P-O Bond in Triarylphosphine Oxides
Journal of Chemical Crystallography
  • Ronald F. See, Saint Louis University
  • Anthony D. Dutoi, Saint Louis University
  • James C. Fettinger, University of Maryland at College Park
  • Peter J. Nicastro, Saint Louis University
  • Joseph W. Ziller, University of California, Irvine
Document Type
Article
Department
Chemistry
DOI
10.1023/A:1022850503138
Publication Date
12-1-1998
Abstract
The crystal structures of the compounds tris(para-chlorophenyl)phosphine oxide {(p-ClPh)3PO} and tris(para-methoxyphenyl)phosphine oxide {(p-OMePh)3PO} were determined by X-ray diffraction methods. (p-ClPh)3PO crystallizes in the space group P-1 (no. 2) with a = 11.828(2), b = 12.645(2), c = 14.072(2) Å, α = 97.90(1), β = 109.45(1), γ = 115.43(1), V = 1692.3(2) Å3 and Z = 4. The mean O–P and C–P distances are 1.481(6) and 1.806(2) Å, respectively, and the mean C–P–C angle is 106.5(1.1). (p-OMePh)3PO crystallizes in the space group P21/c (no. 14) with a = 18.8642 (10), b = 10.3999(5), c = 21.3462(16) Å, β = 115.414(6)°, V= 3782.6(4) Å3, and Z = 8. The mean O–P and C–P distances are 1.484(5) and 1.798(4) Å, respectively, and the mean C–P–C angle is 106.5(1.0). These two structures were analyzed along with the previously determined structures of triphenylphosphine oxide {Ph3PO} and tri-p-tolylphosphine oxide {(p-MePh)3PO}, and IR data were collected on all four compounds. Both the observed P–O distances and the IR stretching frequencies for these triarylphosphine oxides support the interpretation of the P–O bond as having substantial multiple-bond character, with a bond order between 1.7 and 1.8. The para-substituents on these triarylphosphines were shown to have a statistically insignificant effect on the P–O bond.
Citation Information
Ronald F. See, Anthony D. Dutoi, James C. Fettinger, Peter J. Nicastro, et al.. "The Crystal Structures of (p-ClPh)3PO and (p-OMePh)3PO, Including an Analysis of the P-O Bond in Triarylphosphine Oxides" Journal of Chemical Crystallography Vol. 28 Iss. 12 (1998) p. 893 - 898 ISSN: 1074-1542
Available at: http://works.bepress.com/anthony-dutoi/72/