8374. Sarin

Nomenclature

CAS number: 107-44-8
Methylphosphonofluoridic acid 1-methylethyl ester; isopropoxymethylphosphoryl fluoride; isopropylmethylphosphonofluoridate; GB.
C4H10FO2P; mol wt 140.09.
C 34.29%, H 7.19%, F 13.56%, O 22.84%, P 22.11%.

Description and references

Nerve gas; potent cholinesterase inhibitor similar in structure and activity to soman and tabun, q.q.v. Prepn: Holmstedt, Acta Physiol. Scand. 25, suppl. 90, p 106 (1951); Protar 14, 113 (1948); 16, 131 (1950). Additional syntheses: Schrader, B.I.O.S. 714, 41 (1947); B. C. Saunders, Some Aspects of the Chemistry and Toxic Action of Organic Compounds Containing Phosphorus and Fluorine (Cambridge, 1957) p 92 sqq; Bryant et al., J. Chem. Soc. 1960, 1553. Absolute configuration: Benschop et al., Rec. Trav. Chim. 87, 387 (1968). Toxicity study: B. Holmstedt, Pharmacol. Rev. 11, 567 (1959). Epidemiological study of chronic effects: Y. Nishiwaki et al., Environ. Health Perspect. 109, 1169 (2001). Brief review: Schrader, Die Entwicklung neuer insektizider Phosphors"aure-Ester (Verlag Chemie, Weinheim, 1963) p 4; B. L. Harris in Kirk-Othmer Encyclopedia of Chemical Technology vol. 5 (Wiley-Interscience, New York, 4th ed., 1993) pp 795-816.

Chemical structure

Properties

Liquid, d420 1.10. mp -57°. bp760 147°; bp16 56°. Miscible with and hydrolyzed by water. Rapidly hydrolyzed by dil aq sodium hydroxide or sodium carbonate forming relatively non-toxic products. Water alone removes the fluorine atom producing the non-toxic acid CH3PO[OCH(CH3)2]OH. LD50 i.p. in mice: 0.42 mg/kg (Holmstedt, 1959).

Caution

Potential symptoms of overexposure by inhalation are constriction of pupils of the eye, difficulty breathing followed by bronchial constriction, convulsions, and death. Also toxic due to absorption through skin and eyes. See Chem. Eng. News 31, 4676 (1953).

Use

Chemical warfare agent.