Chloro(triphenylphosphine)gold(I)

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.

Chloro(triphenylphosphine)gold(I)

Identifiers
CAS Number	14243-64-2 N
3D model (JSmol)	separate form: Interactive image coordination form: Interactive image
ChemSpider	62872670 N
ECHA InfoCard	100.034.636
EC Number	238-117-6
PubChem CID	10874691
UNII	3RF78267UX Y
CompTox Dashboard (EPA)	DTXSID40931445
InChI InChI=1S/C18H15P.Au.ClH/c1-4-10-16(11-5-1)19(17-12-6-2-7-13-17)18-14-8-3-9-15-18;;/h1-15H;;1H/q;+1;/p-1 N[pubchem] Key: IFPWCRBNZXUWGC-UHFFFAOYSA-M N
SMILES separate form: C1=CC=C(C=C1)P(C2=CC=CC=C2)C3=CC=CC=C3.Cl[Au] coordination form: Cl[Au-][P+](c0ccccc0)(c0ccccc0)c0ccccc0
Properties
Chemical formula	C18H15AuClP
Molar mass	494.71 g·mol−1
Appearance	Colorless solid
Density	1.97 g/cm3
Melting point	236–237 °C (457–459 °F; 509–510 K)
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Precautionary statements	P261, P264, P271, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Preparation and structure

The complex is prepared by reducing chloroauric acid with triphenylphosphine in 95% ethanol:^[1][2]

HAuCl₄ + H₂O + 2 PPh₃ → (Ph₃P)AuCl + Ph₃PO + 3 HCl

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.