122. Acridine

Nomenclature

CAS number: 260-94-6
Dibenzo[b,e]pyridine; 10-azaanthracene.
C13H9N; mol wt 179.22.
C 87.12%, H 5.06%, N 7.82%.

Description and references

Occurs in coal tar. Isoln: Graebe, Caro, Ann. 158, 265 (1871); from high boiling tar oils: Wirth, DE 440771 (1926). Prepn from N-phenylanthranilic acid: Perkin, Clemo, GB 214756 (1923); from Ca-anthranilate: Koller, Krakauer, Monatsh. Chem. 50, 51 (1928) DOI; by passing benzylaniline vapor over red-hot platinum wire: Meyer, Hofmann, ibid. 37, 698 (1916); cf. Ullmann, Ber. 40, 2521 (1907). Absorption spectrum: Pinnow, J. Prakt. Chem. [2] 66, 276 (1902). Toxicity: S. D. Rubbo, Br. J. Exp. Pathol. 28, 1 (1947). Reviews: A. Albert, The Acridines (St. Martin's Press, New York, 2nd ed., 1966); R. M. Acheson, Acridines (Interscience, New York, 2nd ed., 1973).

Chemical structure

Properties

Pale yellow orthorhombic plates, needles from diluted alcohol. Poisonous. There are five crystalline forms of acridine all of which melt below 111°. Purified acridine mp 110-111°; commercial samples mp 107° or mp 109°. Begins to sublime at 100°. bp760 346°; also reported as bp760 >360°. Volatile with steam. Slightly sol in boiling water, liquid ammonia, liquid sulphur dioxide; sparingly sol in light petroleum; freely sol in alcohol, ether, hydrocarbons, carbon disulfide. 1 gm sol in <1 ml boiling benzene or alcohol; 5 ml benzene (20°); 6 ml alcohol (20°); 16 ml of ether (20°); 1.8 ml boiling cyclohexane. d 1.27-1.28. Dilute solns of acridine and its salts have a violet and green fluorescence, respectively. Weak base, colors litmus paper blue, forms yellow crystalline salts with mineral acids. Forms colored quaternary ammonium compounds (acridinium compounds), by the action of alkyl and aryl halides and sulfates. LD50 s.c. in mice: 0.40 g/kg (Rubbo).

Caution

Strongly irritating to skin, mucous membranes. See: Clinical Toxicology of Commercial Products, R. E. Gosselin et al., Eds. (Williams & Wilkins, Baltimore, 5th ed., 1984) Section II, p 384.

Use

Manuf dyes and intermediates; some dyes derived from it are used as antiseptics, e.g. 9-aminoacridine, acriflavine and proflavine. The hydrochloride has been used as reagent for cobalt, iron and zinc.