Chloro(triphenylphosphine)gold(I) or triphenylphosphinegold(I) chloride is a coordination complex with the formula (Ph3P)AuCl. This colorless solid is a common reagent for research on gold compounds.
Ph3PAuCl can also be prepared by treating a thioether complex of gold like (dimethyl sulfide)gold(I) chloride, [(Me2S)AuCl], with triphenylphosphine.[3]
The complex adopts a linear coordination geometry, which is typical of most gold(I) compounds.[4]
It crystallizes in the orthorhombic space group P212121 with a = 12.300(4) Å, b = 13.084(4) Å, c = 10.170(3) Å with Z = 4 formula units per unit cell. [5]
Reactivity
Triphenylphosphinegold(I) chloride is a popular stable precursor for a cationic gold(I) catalyst used in organic synthesis.[3] Typically, it is treated with silver(I) salts of weakly coordinating anions (e.g., X– = SbF6–, BF4–, TfO–, or Tf2N–) to generate a weakly bound Ph3PAu–X complex, in equilibrium with the catalytically-active species [Ph3PAu]+X– in solution. Among these, only the bistriflimide complex Ph3PAuNTf2 can be isolated as the pure compound.[6] The nitrate complex Ph3PAuONO2 and the oxonium species [(Ph3PAu)3O]+[BF4]– are also prepared from the chloride.[7]
As shown in the scheme below, the methyl complex Ph3PAuMe is prepared from triphenylphosphinegold(I) chloride by transmetalation with a Grignard reagent. Further treatment of Ph3PAuMe with methyllithium displaces the phosphine ligand and generates lithium di- and tetramethylaurate, Li+[AuMe2]– and Li+[AuMe4]–, respectively.[8][9]
Reaction scheme of Au(I) and Au(III) organometallic compounds, with (Ph3P)AuCl as the precursor.
References
↑Pierre Braunstein; Hans Lehner; Dominique Matt (1990). A Platinum-Gold Cluster: Chloro-1κCl-Bis(Triethylphosphine-1κP)Bis(Triphenylphosphine)-2κP, 3κP-Triangulo- Digold-Platinum(1 +) Trifluoromethanesulfonate. Inorganic Syntheses. 27. pp. 218–221. doi:10.1002/9780470132586.ch42.
↑M. I. Bruce; B. K. Nicholson; O. Bin Shawkataly (1989). "Synthesis of Gold-Containing Mixed-Metal Cluster Complexes". Inorganic Syntheses. 26. pp. 324–328. doi:10.1002/9780470132579.ch59. ISBN9780470132579.
↑Baenziger, N. C.; Bennett, W. E.; Soborofe, D. M. (1976). "Chloro(triphenylphosphine)gold(I)". Acta Crystallographica Section B32 (3): 962. doi:10.1107/S0567740876004330.
↑Borissova, Alexandra O.; Korlyukov, Alexander A.; Antipin, Mikhail Yu.; Lyssenko, Konstantin A. (2008). "Estimation of Dissociation Energy in Donor−Acceptor Complex AuCl·PPh3via Topological Analysis of the Experimental Electron Density Distribution Function". The Journal of Physical Chemistry A112 (46): 11519–22. doi:10.1021/jp807258d. PMID18959385.
↑Mézailles, Nicolas; Ricard, Louis; Gagosz, Fabien (2005-09-01). "Phosphine Gold(I) Bis-(trifluoromethanesulfonyl)imidate Complexes as New Highly Efficient and Air-Stable Catalysts for the Cycloisomerization of Enynes". Organic Letters7 (19): 4133–4136. doi:10.1021/ol0515917. ISSN1523-7060. PMID16146370.
↑A. M. Mueting, B. D. Alexander, P. D. Boyle, A. L. Casalnuovo, L. N. Ito, B. J. Johnson, L. H. Pignolet "Mixed-Metal-Gold Phosphine Cluster Compounds" Inorganic Syntheses, 1992, Volume 29, Pages 279–298, 2007. doi:10.1002/9780470132609.ch63