Tris(trimethylsilyl)phosphine is the organophosphorus compound with the formula P(SiMe3)3 (Me = methyl). It is a colorless liquid that ignites in air and hydrolyses readily.[1]

Preferred IUPAC name
  • 15573-38-3 checkY
3D model (JSmol)
  • Interactive image
  • 239909
ECHA InfoCard 100.154.516 Edit this at Wikidata
EC Number
  • 626-081-8
  • 272683
  • DTXSID70297687 Edit this at Wikidata
  • InChI=1S/C9H27PSi3/c1-11(2,3)10(12(4,5)6)13(7,8)9/h1-9H3
  • C[Si](C)(C)P([Si](C)(C)C)[Si](C)(C)C
Molar mass 250.544 g·mol−1
Appearance colorless liquid
Density 0.863 g/cm3
Melting point 24 °C (75 °F; 297 K)
Boiling point 243–244 °C (469–471 °F; 516–517 K)
Occupational safety and health (OHS/OSH):
Main hazards
poison, inflammable
GHS labelling:
GHS05: CorrosiveGHS07: Exclamation mark
H250, H252, H315, H319, H335
P210, P222, P235+P410, P261, P264, P271, P280, P302+P334, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P370+P378, P403+P233, P405, P407, P413, P420, P422, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references


Tris(trimethylsilyl)phosphine is prepared by treating trimethylsilyl chloride, white phosphorus, and sodium-potassium alloy:[2]

1/4 P4 + 3 Me3SiCl + 3 K → P(SiMe3)3 + 3 KCl

Several other methods exist.[1]

Copper phosphide cluster Cu96P30{P(SiMe3)2}6(PEt3)18 with C and H atoms omitted for clarity (red=Cu, purple=P, tan=Si). Tris(trimethylsilyl)phosphine the reagent used to install the phosphide ligands.[3]


The compound hydrolyzes to give phosphine:

P(SiMe3)3 + 3 H2O → PH3 + 3 HOSiMe3

Treatment of certain acyl chlorides with tris(trimethylsilyl)phosphine gives phosphaalkynes, one example being tert-butylphosphaacetylene.[4]

Synthesis of a phosphaalkyne using tris(trimethylsilyl)phosphine.

Reaction with potassium tert-butoxide cleaves one P-Si bond, giving the phosphide salt:[5]

P(SiMe3)3 + KO-t-Bu → KP(SiMe3)2 + Me3SiO-t-Bu

It is a reagent in the preparation of metal phosphido clusters by reaction with metal halides or carboxylates. In such reactions the silyl halide or silyl carboxylate is liberated as illustrated in this idealized reaction:

P(SiMe3)3 + 3 CuCl → Cu3P + 3 ClSiMe3


Tris(trimethylsilyl)phosphine spontaneously ignites in air, thus it is handled using air-free techniques.


  1. ^ a b Kosarev, Sergey A.; Collier, Steven J. (2011). tris(trimethylsilyl)phosphin. Handbook of Reagents for Organic Synthesis: Reagents for Silicon-Mediated Organic Synthesis. pp. 422–427. doi:10.1002/047084289X.rn01332. ISBN 978-0471936237.
  2. ^ Becker, Gerd; Schmidt, Helmut; Uhl, Gudrun; Uhl, Werner (1990). Tris(trimethylsilyl)phosphine and lithium bis(trimethylsilyl)phosphide·bis(tetrahydrofuran). Inorganic Syntheses. Vol. 27. pp. 243–9. doi:10.1002/9780470132586.ch48. ISBN 9780470132586.
  3. ^ Fenske, D.; Holstein, W. (1994). "[Cu96P30{P(SiMe3)2}6(PEt3)18], a New Phosphorus-Bridged Copper Cluster". Angew. Chem. Int Ed. Engl. 33 (12): 1290–1292. doi:10.1002/anie.199412901.
  4. ^ M. Regitz (1990). "Phosphaalkynes: new building blocks in synthetic chemistry". Chem. Rev. 90: 191–213. doi:10.1021/cr00099a007..
  5. ^ Russell, Christopher A.; Townsend, Nell S. (2012). "Phosphaalkynes". In Kamer, Paul C. J.; Van Leeuwen, Piet W. N. M (eds.). Phosphorus(III) Ligands in Homogeneous Catalysis. Wiley-VCH. pp. 343–354. doi:10.1002/9781118299715.ch11. ISBN 9781118299715.