Trixylyl phosphate

Trixylyl phosphate
Names
	Other names tris(dimethylphenyl) phosphate; Tri-dimethyl phenyl phosphate; Tri-xylenyl phosphate;
Identifiers
CAS Number	25155-23-1;
ECHA InfoCard	100.042.419
EC Number	246-677-8;
CompTox Dashboard (EPA)	DTXSID9026267 ;
Properties
Chemical formula	C24H27O4P
Molar mass	410.450 g·mol−1
Appearance	Viscous liquid
Density	1.142
Melting point	−20 °C (−4 °F; 253 K)
Boiling point	394 °C (741 °F; 667 K)
Solubility in water	20 µg/L
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H360F
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Trixylyl phosphate (TXP) is an aromatic phosphate ester. It was historically used as a flame retardant for acetate plastics (cellulose nitrate and cellulose acetate) and PVC. It also saw significant use as a fire-resistant hydraulic fluid.

Trixylyl phosphate is now banned or restricted in several jurisdictions, due to its poor safety profile. Short term exposure can cause organophosphate-induced delayed neuropathy,^[1] but it is also regarded as a reproductive toxin. In the EU is classified as a substance of very high concern, requiring authorisation to be used.

Synthesis

Trixylyl phosphate is prepared industrially by the reaction of phosphoryl chloride with mixed xylenols. In practise this produces a range of products.

References

^ Mortensen, A; Ladefoged, O (1992). "Delayed neurotoxicity of trixylenyl phosphate and a trialkyl/aryl phosphate mixture, and the modulating effect of atropine on tri-o-tolyl phosphate-induced neurotoxicity". Neurotoxicology. 13 (2): 347–54. PMID 1436754.

[1] Mortensen, A; Ladefoged, O (1992). "Delayed neurotoxicity of trixylenyl phosphate and a trialkyl/aryl phosphate mixture, and the modulating effect of atropine on tri-o-tolyl phosphate-induced neurotoxicity". Neurotoxicology. 13 (2): 347–54. PMID 1436754.

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