Triphenyl phosphite explained

Triphenyl phosphite is the organophosphorus compound with the formula P(OC6H5)3. It is a colourless viscous liquid.

Preparation

Triphenylphosphite is prepared from phosphorus trichloride and phenol in the presence of a catalytic amount of base:

PCl3 + 3 HOC6H5 → P(OC6H5)3 + 3 HCl

Reactions

Triphenylphosphite is a precursor to trimethylphosphine, it serves as a source of P3+ that is less electrophilic than phosphorus trichloride:[1]

(C6H5O)3P + 3CH3MgBr → P(CH3)3 + 3"MgBrOC6H5"

Triphenylphosphite is quaternized by methyl iodide:[2]

(C6H5O)3P + CH3I → [CH<sub>3</sub>(C<sub>6</sub>H<sub>5</sub>O)<sub>3</sub>P]+I

Coordination complexes

Triphenylphosphite is a common ligand in coordination chemistry. It forms zero-valent complexes of the type M[P(OC<sub>6</sub>H<sub>5</sub>)<sub>3</sub>]4 (M = Ni, Pd, Pt). The nickel complex can be prepared by displacement of the diene from bis(cyclooctadiene)nickel:[3]

Ni(COD)2 + 4 P(OC6H5)3 → Ni[P(OC<sub>6</sub>H<sub>5</sub>)<sub>3</sub>]4 + 2 CODRelated complexes are homogeneous catalysts for the hydrocyanation of alkenes. It also forms a variety of Fe(0) and Fe(II) complexes such as the dihydride H2Fe[P(OC<sub>6</sub>H<sub>5</sub>)<sub>3</sub>]4.[4]

Polyamorphism

Triphenylphosphite is a notable example of polyamorphism in organic compounds, namely it exists in two different amorphous forms at temperatures about 200 K.[5] One polymorphic modification of triphenyl phosphite was obtained by means of crystallization in ionic liquids.[6]

Notes and References

  1. Book: . Leutkens, M. L. Jr. . Sattelberger, A. P. . Murray, H. H. . Basil, J. D. . John P. Fackler Jr. . Fackler, J. P. Jr. . Trimethylphosphine . 1990 . Inorganic Syntheses . 28 . 305–310 . 10.1002/9780470132593.ch76. 978-0-470-13259-3 .
  2. H. N. Rydon. 10.15227/orgsyn.051.0044. Alkyl Iodides: Neopentyl Iodide and Iodocyclohexane. Organic Syntheses. 1971. 51. 44.
  3. Book: 10.1002/9780470132487.ch34. Olefin, Acetylene, Phosphine, Isocyanide, and Diazene Complexes of Nickel(0). 1977. Ittel. Steven D.. Inorganic Syntheses. 117–124. XVII. 978-0-470-13248-7.
  4. 10.1021/ja00768a022. Stereochemically Nonrigid Six-Coordinate Molecules. II. Preparations and Reactions of Tetrakis(organophosphorus)metal Dihydride Complexes. 1972. Gerlach. D. H.. Peet. W. G.. Muetterties. E. L.. Journal of the American Chemical Society. 94. 4545. 13.
  5. 10.1021/jp9530820. Supercooled Liquids and Polyamorphism†. 1996. Ha. Alice. Cohen. Itai. Zhao. Xiaolin. Lee. Michelle. Kivelson. Daniel. The Journal of Physical Chemistry. 100. 1–4.
  6. D.G. Golovanov, K.A. Lyssenko, M.Yu. Antipin, Ya.S. Vygodskii, E.I. Lozinskaya, A.S. Shaplov. ”Long-awaited polymorphic modification of triphenyl phosphite“, Cryst. Eng. Comm., 2005, v. 7, no. 77, P.465 – 468. doi: 10.1039/b505052a