Tricyclohexylphosphine

Tricyclohexylphosphine is the tertiary phosphine with the formula P(C₆H₁₁)₃. Commonly used as a ligand in organometallic chemistry, it is often abbreviated to PCy₃, where Cy stands for cyclohexyl. It is characterized by both high basicity (pK_a = 9.7)^[1] and a large ligand cone angle (170°).^[2][3]

Tricyclohexylphosphine

Names
Preferred IUPAC name Tricyclohexylphosphane
Other names P(Cy)3 PCy3
Identifiers
CAS Number	2622-14-2 Y
3D model (JSmol)	Interactive image Interactive image
ChemSpider	68315 N
ECHA InfoCard	100.018.246
PubChem CID	75806
UNII	34HJS55VCG Y
CompTox Dashboard (EPA)	DTXSID9062562
InChI InChI=1S/C18H33P/c1-4-10-16(11-5-1)19(17-12-6-2-7-13-17)18-14-8-3-9-15-18/h16-18H,1-15H2 N Key: WLPUWLXVBWGYMZ-UHFFFAOYSA-N N InChI=1/C18H33P/c1-4-10-16(11-5-1)19(17-12-6-2-7-13-17)18-14-8-3-9-15-18/h16-18H,1-15H2 Key: WLPUWLXVBWGYMZ-UHFFFAOYAM
SMILES C1(CCCCC1)P(C2CCCCC2)C3CCCCC3 C1CCC(CC1)P(C2CCCCC2)C3CCCCC3
Properties
Chemical formula	C18H33P
Molar mass	280.43 g mol−1
Appearance	white solid
Melting point	82 °C (180 °F; 355 K)
Solubility in water	organic solvents
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	toxic
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

Important complexes containing P(Cy)₃ ligands include the 2005 Nobel Prize-winning Grubbs' catalyst and the homogeneous hydrogenation catalyst Crabtree's catalyst.

• 
  Grubbs' catalyst (first generation)
• 
  Crabtree's catalyst