Tris(hydroxymethyl)phosphine

Tris(hydroxymethyl)phosphine

Identifiers
CAS Number	2767-80-8  Y
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL279546
ChemSpider	68500
ECHA InfoCard	100.018.587
EC Number	220-445-6
PubChem CID	76001
UNII	Y6TG7WF7OQ
CompTox Dashboard (EPA)	DTXSID0062634
InChI InChI=1S/C3H9O3P/c4-1-7(2-5)3-6/h4-6H,1-3H2 Key: JMXMXKRNIYCNRV-UHFFFAOYSA-N
SMILES C(O)P(CO)CO
Properties
Chemical formula	C3H9O3P
Molar mass	124.076 g·mol−1
Appearance	white solid
Density	1.16 g/cm3
Melting point	51–53 °C (124–127 °F; 324–326 K)
Boiling point	decomposes
Solubility in water	alcohols, dmf
Hazards
GHS labelling: [1]
Pictograms
Signal word	Danger
Hazard statements	H301, H315, H318, H335
Precautionary statements	P261, P264, P264+P265, P270, P271, P280, P301+P316, P302+P352, P304+P340, P305+P354+P338, P317, P319, P321, P330, P332+P317, P362+P364, P403+P233, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Tris(hydroxymethyl)phosphine is the organophosphorus compound with the formula P(CH₂OH)₃. It is a white solid. The compound is multifunctional, consisting of three alcohol functional groups and a tertiary phosphine. It is prepared by treating tetrakis(hydroxymethyl)phosphonium chloride with strong base: ^{[2] [3]}

[P(CH₂OH)₄]Cl + NaOH → P(CH₂OH)₃ + H₂O + H₂C=O + NaCl

The compound can be prepared on a large scale using triethylamine as base and as solvent. ^[4]

Reactions

The compound forms complexes with a variety of metals. These complexes display some solubility in water but more so in methanol. ^[4] The compound decomposes violently to phosphine and formaldehyde upon attempted distillation. In air, it oxidizes to the oxide.

Upon heating with hexamethylenetetramine, it converts to the water-soluble ligand 1,3,5-triaza-7-phosphaadamantane (PTA). ^{[5] [6]}

Tris(hydroxymethyl)phosphine can also be used to synthesize the heterocycle, N-Boc-3-pyrroline by ring-closing metathesis using Grubbs' catalyst (bis(tricyclohexylphosphine)benzylidineruthenium dichloride). N-Boc-diallylamine is treated with Grubbs' catalyst, followed by tris(hydroxymethyl)phosphine. The carbon-carbon double bonds undergo ring closure, releasing ethene gas, resulting in N-Boc-3-pyrroline. ^[2] The hydroxymethyl groups on THPC undergo replacement reactions when THPC is treated with α,β-unsaturated nitrile, acid, amide and epoxides. For example, base induces condensation between THPC and acrylamide with displacement of the hydroxymethyl groups. (Z = CONH₂)

[P(CH₂OH)₄]Cl + NaOH + 3CH₂=CHZ → P(CH₂CH₂Z)₃ + 4CH₂O + H₂O + NaCl

Similar reactions occur when THPC is treated with acrylic acid; only one hydroxymethyl group is displaced, however. ^[7]

References

1. "Tris(hydroxymethyl)phosphine". pubchem.ncbi.nlm.nih.gov.
2. Ferguson, Marcelle L.; O’Leary, Daniel J.; Grubbs, Robert H. (2003). "Ring-Closing Metathesis Synthesis of N-BOC-3-Pyrroline". Organic Syntheses . 80: 85. doi:10.15227/orgsyn.080.0085 .
3. M. Caporali, L. Gonsalvi, F. Zanobini, M. Peruzzini (2010). "Functional Ligands and Complexes". Inorganic Syntheses. Vol. 35. pp. 92–108. doi:10.1002/9780470651568.ch5. ISBN   978-0-471-68255-4.
4. Ellis, James W.; Harrison, Karl N.; Hoye, Peter A. T.; Orpen, A. Guy; Pringle, Paul G.; Smith, Martin B. (1992). "Water-Soluble Tris(hydroxymethyl)phosphine Complexes with Nickel, Palladium, and Platinum. Crystal Structure of Pd[P(CH₂OH)₃]₄^.CH₃OH". Inorganic Chemistry. 31 (14): 3026–3033. doi:10.1021/ic00040a009.
5. Daigle, D. J.; Pepperman, A. B.; Vail, Sidney L. (1974). "Synthesis of a Monophosphorus Analog of Hexamethylenetetramine". Journal of Heterocyclic Chemistry. 11 (3): 407–408. doi:10.1002/jhet.5570110326.
6. Daigel, Donald J.; Decuir, Tara J.; Robertson, Jeffrey B.; Darensbourg, Donald J. (2007). 1,3,5-Triaz-7-Phosphatricyclo[3.3.1.1^3,7]Decane and Derivatives. Inorganic Syntheses. Vol. 32. pp. 40–42. doi:10.1002/9780470132630.ch6. ISBN   978-0-470-13263-0.
7. Vullo, W. J. (1966). "Hydroxymethyl Replacement Reactions of Tetrakis(hydroxymethyl)phosphonium Chloride". Ind. Eng. Chem. Prod. Res. Dev. 58 (4): 346–349. doi:10.1021/i360020a011.