7109. Pentachlorophenol

Nomenclature

CAS number: 87-86-5
2,3,4,5,6-Pentachlorophenol; 1-hydroxypentachlorobenzene; penchlorol; PCP.
C6HCl5O; mol wt 266.34.
C 27.06%, H 0.38%, Cl 66.56%, O 6.01%.

Description and references

Broad spectrum biocide; prepd by the chlorination of phenol in the presence of a catalyst. GC-MS determn in plasma: Y. Zhou et al., Chemosphere 70, 256 (2007) DOI. Review of properties, uses, and environmental chemistry: D. G. Crosby et al., Pure Appl. Chem. 53, 1051-1080 (1981) DOI; of toxicology and human exposure: Toxicological Profile for Pentachlorophenol (PB2001-109106, 2001) 316 pp.

Chemical structure

Properties

Needle-like crystals, mp 190-191°. Poisonous. bp ≈309-310° (dec). d422 1.978. pKa (25°): 4.70. Log P (octanol/water): 2.15; Log P (hexane/water): 5.01. Vapor pressure (torr): 1.7×10-5 at 0°; 1.7×10-4 at 20°; 0.14 at 100°; 758.4 at 300°. Soly at 25° (g/l): methanol 180; acetone 50; benzene 15. Soly in water (g/l): 0.005 at 0°; 0.014 at 20°; 0.085 at 70°. uv max: 303 nm (ε 2900). LD50 in male, female rats (mg/kg): 146, 175 orally; see T. B. Gaines, Toxicol. Appl. Pharmacol. 14, 515 (1969) DOI PubMed.

Derivative

Sodium salt.

Nomenclature

CAS number: 131-52-2
Sodium pentachlorophenate; sodium pentachlorophenoxide; NaPCP.
C6Cl5NaO; mol wt 288.32.
C 24.99%, Cl 61.48%, Na 7.97%, O 5.55%.

Properties

White crystalline solid. Soly at 25° (g/l): methanol 22; acetone 37. Soly in water (g/l): 22.4 at 20°; 33 at 30°. Insol in benzene. LC50 in goldfish: 0.22 mg/l (Crosby).

Caution

Potential symptoms of overexposure are irritation of eyes, nose, throat; sneezing, cough; weakness, anorexia, weight loss; sweating; headache, dizziness; nausea, vomiting; dyspnea, chest pain; high fever. Direct contact may cause dermatitis. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 242; Patty's Industrial Hygiene and Toxicology vol. 2B, G. D. Clayton, F. E. Clayton, Eds. (Wiley-Interscience, New York, 1994) pp 1603-1613.

Use

Insecticide for termite control; molluscicide; general herbicide. Antimicrobial preservative and fungicide for wood, wood products, starches, textiles, paints, adhesives, leather, pulp, paper, industrial waste systems, building materials.