2856. Deet

Nomenclature

CAS number: 134-62-3
N,N-Diethyl-3-methylbenzamide; N,N-diethyl-m-toluamide; M-Det; m-DETA; ENT-20218; m-Delphene; Detamide; Dieltamid; Flypel; Metadelphene (Hercules); OFF! (SC Johnson); Repel (WPC).
C12H17NO; mol wt 191.27.
C 75.35%, H 8.96%, N 7.32%, O 8.36%.

Description and references

Technical deet contains a minimum of 95% meta isomer; commercial formulations contain 11.27-100% deet by weight. Prepn from m-toluoyl chloride and diethylamine in benzene or ether: Maxim, Bull. Soc. Chim. Romania 11, 29 (1929); Chem. Zentralbl. 1929, II, 2324, C.A. 24, 94 (1930); Beilstein 9, II, 325; E. T. McCabe et al., J. Org. Chem. 19, 493 (1954). Repellent activity vs mosquitoes: I. H. Gilbert et al., J. Econ. Entomol. 48, 741 (1955). Toxicity study: A. M. Ambrose et al., Toxicol. Appl. Pharmacol. 1, 97 (1959). Metabolism: L. Blomquist, W. Thorsell, Acta Pharmacol. Toxicol. 41, 235 (1977). Physical, chemical and toxicological properties and insect repellent efficacy: Pesticide Registration Standard - Deet (U.S. EPA 504/RS-81-004, Washington, D.C., 1980) 82 pp. HPLC determn including metabolites: J. M. Yeung, W. G. Taylor, Drug Metab. Dispos. 16, 600 (1988). Comparative study of efficacy vs mosquitoes: M. S. Fradin, J. F. Day, N. Engl. J. Med. 347, 13 (2002). Review of safety: T. G. Osimitz, R. H. Grothaus, J. Am. Mosq. Control Assoc. 11, 274-278 (1995); and pharmacokinetics and formulation: H. Qiu et al., ibid. 14, 12-27 (1998).

Chemical structure

Properties

Nearly colorless to amberlike liquid, faint aromatic odor. bp1.0 111°. d25 0.990-1.000. nD25 1.5206. Flash pt, open cup: 311°F (155°C). Partition coefficient (octane/water): 105. Vapor pressure at 25°: 1.67 × 10-3 mm Hg. Viscosity at 30°: 13.3 cP. Soly in water at 25°: 9.9 mg/ml. Practically insol in glycerin. Miscibile with ethanol, ether, isopropanol, chloroform, benzene, and carbon disulfide. Hygroscopic. Light sensitive. LD50 orally in male rats (ml/kg): 2.43; in female rats: 1.78; dermally in rabbits: ≥3.18. LC50 by inhalation in rats (mg/l): 5.95 (U.S. EPA).

Caution

Direct contact may cause eye irritation (U.S. EPA). See also: Clinical Toxicology of Commercial Products, R. E. Gosselin et al., Eds. (Williams & Wilkins, Baltimore, 5th ed., 1984) Section II, p 346.

Use

Insect repellent.