Triphos

Chembox new
ImageFile = Triphos.png IUPACName = 1,1,1-Tris(diphenylphosphinomethyl)ethane
OtherNames = Triphos,
tdppme,
tdme
Section1 = Chembox Identifiers
CASNo = 22031-12-5
Section2 = Chembox Properties
Formula = C₄₁H₃₉P₃
MolarMass = 624.67 g/mol
Appearance = white crystals
Solubility = Insoluble
MeltingPt = 99-102 °C
Section7 = Chembox Hazards
MSDS = [http://www.sigmaaldrich.com/cgi-bin/hsrun/Suite7/Suite/HAHTpage/Suite.HsSigmaAdvancedSearch.formAction Triphos MSDS]
SPhrases = 22-24/25

1,1,1-Tris(diphenylphosphinomethyl)ethane, also known as triphos, is an organophosphorus compound with the formula CH₃C [CH₂PPh₂] ₃. Triphos, an air sensitive white solid, is a widely used tridentate ligand in inorganic and organometallic chemistry.

ynthesis

Triphos is prepared by the reaction of sodium diphenylphosphide (Ph₂PNa) and CH₃C(CH₂Cl)₃: [cite journal | journal = J. Chem. Soc. | year = 1962 | pages = 1490–1494 | doi = 10.1039/JR9620001490 | title = 283. The preparation of di- and tri-tertiary phosphines | author = W. Hewertson and H. R. Watson]

:Ph₃P + 2 Na → Ph₂PNa + NaPh:Ph₂PNa + CH₃C(CH₂Cl)₃ → CH₃C [CH₂PPh₂] ₃
The required sodium diphenylphosphide is conveniently obtained by cleaving triphenylphosphine with sodium in liquid ammonia, treating it with water, and then extracting it with ether.

Coordination Properties

Facial Coordination

Triphos forms complexes with many transition metals. It usually serves as a tripodal ligand that occupies three facial sites. cite journal | author = Fernández, Eduardo J.; Gimeno, M. Concepción; Laguna, Antonio; Laguna, Mariano; López-de-Luzuriaga, José M.; & Olmos, Elena | year = 1996 | title = Different Coordination modes of 1,1,1-tris(diphenylphosphinomethyl) ethane Ligand in Gold(I) and Gold(III) Complexes | journal = Journal of Organometallic Chemistry | volume = 514 | pages = 169 | doi = 10.1016/0022-328X(95)06025-R] Triphos confers high thermal stability to its complexes, thus triphos-metal complexes are used to analyze mechanistic aspects of homogenous catalysts. [cite journal | author = Bianchini, Claudio; Marchi, Andrea; Marvelli, Lorenza; Peruzzini, Maurizio; Romerosa, Antonio; Rossi, Roberto | year = 1996 | title = Multiple Re-C Bonds at the [{MeC(CH₂PPh₂)₃}Re(CO)₂] + Auxiliary | journal =
Organometallics | volume = 15 | pages = 3804 | doi = 10.1021/om9602264] For example, rhodium forms complexes with CH₃C [CH₂PPh₂] ₃ like [(triphos)RhCl(C₂H₄)] , [(triphos)RhH(C₂H₄)] , and [(triphos)Rh(C₂H₅)(C₂H₄)] , which are steps in a catalytic cycle for hydrogenation of alkenes, alkynes, and organic nitriles. [cite journal | author = Bianchini, Claudio; Meli, Andrea; Peruzzini, Maurizio; Vizza, Francesco | year = 1990 | title = Tripodal Polyphosphine Ligands in Homogeneous Catalysis. 1. Hydrogenation and Hydroformylation of Alkynes and Alkenes Assisted by Organorhodium Complexes with [{MeC(CH₂PPh₂)₃}Re(CO)₂] | journal = Organometallics | volume = 9 | pages = 226 | doi = 10.1021/om00115a035]

Non-Facial Coordination

Triphos sometimes acts as a bidentate-chelating ligand. Illustrative cases include "fac"- [Mn(CO)₃Br(ɳ²-triphos)] and [M(CO)₄(ɳ²-triphos)] ,where M is Cr, Mo, or W. Triphos acts as a tridentate-bridging ligand in an icosohedral Au₁₃ cluster. The phosphine bridges three chlorogold(I) groups to form the tripod molecule of trichloro-1,1,1-(diphenylphosphinomethyl)ethanetrigold(I), CH₃C [CH₂PPh₂AuCl] ₃. cite journal | author = Cooper, Mervyn K.; Henrick, Kim; McPartlin, Mary; & Latten, Jozef L. | year = 1982 | title = The synthesis and X-ray structure of trichloro-1,1,1-(diphenylphosphinomethyl)ethanetrigold(I) | journal = Inorganica Chimica Acta | volume = 65 | pages = L185 | doi = 10.1016/S0020-1693(00)93540-0]

References