Title: Thionine
CAS Registry Number: 135-59-1
CAS Name: 3,7-Diaminophenothiazin-5-ium chloride
Additional Names: Lauth's violet; C.I. 52000
Molecular Formula: C12H10ClN3S
Molecular Weight: 263.75
Percent Composition: C 54.65%, H 3.82%, Cl 13.44%, N 15.93%, S 12.16%
Literature References: Prepn from p-phenylenediamine: Lauth, Compt. Rend. 82, 1441 (1876); Bull. Soc. Chim. Fr. [2] 26, 422 (1876); Bernthsen, DE 25150 (1883 to BASF), Frdl. 1, 253; Loiseleur, Ann. Inst. Pasteur 86, 262 (1954); Loiseleur, Petit, Compt. Rend. 250, 2573 (1960); Balestic, Magat, C.A. 55, 23542g (1961). See also: Colour Index vol. 4 (3rd ed., 1971) p 4469.
Properties: Blackish-green glistening needles. Absorption max (water): 602.5 nm. Difficultly sol in cold, easily sol in hot water, giving first a blue, then a violet soln. The soln becomes somewhat bluer when HCl is added. Brownish-red precipitate with NaOH. Yellowish-green soln with concd H2SO4 which upon dilution turns blue, then violet on further dilution.
Absorption maximum: Absorption max (water): 602.5 nm
Use: For general nuclear staining; for counting bacteria in milk; as antioxidant for linseed oil. Has been used as catalyst in condensation of 1,3-butadienyl ethyl ether with maleic anhydride. |