Tributylphosphine

chembox new
ImageFile=tributylphosphine.png ImageSize=150px
ImageFile1=Tributylphosphine-3D-vdW.png IUPACName=Tributylphosphine
Section1 = Chembox Identifiers
CASNo=998-40-3
EINECS=213-651-2
SMILES=CCCCP(CCCC)CCCC
DispInChI=1/C12H27P/c1-4-7- 10-13(11-8-5-2)12-9-6 -3/h4-12H2,1-3H3
InChI=1/C12H27P/c1-4-7-10-13(11-8-5-2)12-9-6-3/h4-12H2,1-3H3
Section2=Chembox Properties
C = 12 | H = 27 | P = 1
Formula=Csu|b=12Hsu|b=27P
MolarMass=204.25 g/mol
Appearance=Colorless oily liquid
Density=0.81 g/ml
Solubility=negligeable
Solvent=Water
MeltingPtK=213
BoilingPtK=513
Boilink_notes=(150 °C @ 50 mmHg)
Dipole=?
Section3=Chembox Hazards
NFPA-H = 1
NFPA-F = 3
NFPA-R = 2
NFPA-O =
RPhrases = R17 R21 R22 R34 R38
MainHazards=Stench, Flammable, Corrosive
FlashPt=117 °C
Autoignition=168 °C
Section4=Chembox Supplement
Section5=Chembox Related
OtherFunctn=Trimethylphosphine Triphenylphosphine
Function=Tertiary phosphine

Tributylphosphine, [Tributylphosphine is the most widely used name for this compound. However Iupac nomenclature prefers the name tributylphosphane, which is also the U.S. proper shipping name (49 CFR 172.101).] formula P(Csu|b=4Hsu|b=9)su|b=3 or PBusu|b=3, is a tertiary phosphine, most commonly encountered as a ligand in transition metal complexes. It its an oily liquid at room temperature, with a nauseating odour. It reacts slowly with atmospheric oxygen, and rapidly with other oxidizing agents, to give the corresponding phosphine oxide. It is usually handled using air-free techniques.

Preparation

Tributylphosphine is prepared industrially by the addition of phosphine to butene: the addition proceeds by a free radical mechanism, and so the Markovnikov rule is not followed.::PHsu|b=3 + 3CHsu|b=2=CHCHsu|b=2CHsu|b=3 → P(CHsu|b=2CHsu|b=2CHsu|b=2CHsu|b=3)su|b=3Tributylphosphine can be prepared in the laboratory by reaction of the appropriate Grignard reagent with phosphorus trichloride although, as it is commercially available at reasonable prices, it is rare to have to perform the small-scale preparation.::3BuMgCl + PClsu|b=3 → PBusu|b=3 + 3MgClsu|b=2

Use

Tributylphosphine finds some industrial use as a catalyst modifier in the cobalt-catalyzed hydroformylation of alkenes, where it greatly increases the ratio of straight-chain aldehydes to branched-chain aldehydes in the product mixture. [cite journal | last = Bell | first = P. | coauthors = Rupilus, W.; & Asinger, F. | year = 1968 | title = Zur Frage der Isomerenbildung bei der Hydroformylierung Höhermolekularer Olefine mit Komplexen Kobalt- und Rhodiumkatalysatoren | journal = Tetrahedron Lett. | pages = 3262–66] However, tricyclohexylphosphine is even more effective for this purpose (although more expensive) and, in any case, rhodium catalysts are usually preferred to cobalt catalysts for the hydroformylation of alkenes.

Tributylphosphine is also a common ligand for the preparation of complexes of transition metals in relatively low oxidation states, as it is cheap and less air-sensitive. It has a conveniently low volatility, which makes it easier to handle than other trialkylphosphines. Although its complexes are generally highly soluble, they are often more difficult to crystallize compared to complexes of more rigid phosphines. Furthermore, the 1H NMR properties are less easily interpreted and can mask signals for other ligands. Compared to other tertiary phosphines, it is relatively compact (cone angle: 136°) and relatively basic (χ-parameter: 5.25 cm^–1) [cite journal | last = Rahman | first = M. M. | coauthors = Liu, H. Y.; Prock, A.; & Giering, W. P. | year = 1987 | title = Steric and Electronic Factors influencing Transition-Metal–Phosphorus(III) Bonding | journal = Organometallics | volume = 6 | pages = 650–58 | doi = 10.1021/om00146a037]

Hazards

The main laboratory inconvenience of tributylphosphine is its extremely strong and unpleasant smell. All manipulations must be carried out in a efficient fume hood, and glassware which has come into contact with the compound must be decontaminated before leaving the hood. Because tributylphosphine must be protected from the atmosphere, it is usually handled using syringe techniques. The manipulation of large quantities requires specific precautions to prevent the release of the vapour into the environment. For transport purposes, it is classified as a "spontaneously flammable liquid" (group 4.2), although this is rarely a significant problem in the laboratory use of small quantities: it may not be transported by air. [49 CFR 172.101.]

References

External links

* [http://nmrshiftdb.pharmazie.uni-marburg.de/portal/js_pane/P-Results/nmrshiftdbaction/showDetailsFromHome/molNumber/10016983/tab/1;jsessionid=A6990EEA509D6C15299CDCD10C36A8F0?&tab=0 NMR data for tributylphosphine]
* [http://physchem.ox.ac.uk/MSDS/TR/tributylphosphine.html Material Safety Data Sheet]
* [http://www.sigmaaldrich.com/sigma/bulletin/t7567bul.pdf Use of tributyl phosphine for the reduction of disulfide bonds in proteins]

InChI
InChI=1/C12H27P/c1-4-7-10-13(11-8-5-2)12-9-6-3/h4-12H2,1-3H3
InChIKey=TUQOTMZNTHZOKS-UHFFFAOYAQ
CASRN=998-40-3
PIN=Tributylphosphane