6223. MMT

Nomenclature

CAS number: 12108-13-3
Tricarbonyl[(1,2,3,4,5-η)-1-methyl-2,4-cyclopentadien-1-yl]manganese; methylcyclopentadienylmanganese tricarbonyl; MCMT; tricarbonyl(η5-methylcyclopentadienyl)manganese(I); TCMn; AK-33X.
C9H7MnO3; mol wt 218.09.
C 49.56%, H 3.24%, Mn 25.19%, O 22.01%.

Description and references

Organometallic antiknock compound used to increase the octane quality of fuel. Prepn: J. E. Brown et al., US 2818417 (1957 to Ethyl Corp.). Evaluation of antiknock properties: R. J. Riggs et al., Proc. 37th Natural Gas Assoc. Am. 1958, 51. Effect on auto emissions: W. R. Pierson et al., J. Air Pollut. Control. Assoc. 28, 692 (1978). Use as dopant in Mn deposition: K. Hirabayashi, H. Kozawaguchi, Jpn. J. Appl. Phys. 25, 711 (1986). Pyrolysis mechanism in deposition: S. Wen-bin et al., J. Cryst. Growth 113, 1 (1991); I. M. T. Davidson et al., J. Mater. Chem. 4, 13 (1994). GC determn in gasoline: W. A. Aue et al., Anal. Chem. 62, 2453 (1990); and in air: V. S. Gaind et al., Analyst 117, 161 (1992). Review as octane enhancer: J. D. Bailie, Oil Gas J. 74, 69-72 (1976); D. P. Hollrah, A. M. Burns, ibid. 89, 86-90 (1991). Review of toxicology: J. Stara et al., Proc. 4th Ann. Conf Environment. Toxicol. AD-781 031, 251-270 (1973); P. J. Abbott, Sci. Total Environ. 67, 247-255 (1987); and environmental assessment: D. R. Lynam et al., ibid. 93, 107-114 (1990.)

Chemical structure

Properties

Yellow orange liquid, fp -0.75°. nD20 1.5873. d204 1.3942. Vapor pressure ranges from 8 mm at 100° to 360.6 mm at 200°. Readily sol in hydrocarbons and the usual organic solvents including hexane, alchohols, ether, acetone, ethylene glycol, lubricating oils, and hydrocarbon fuels, such as gasoline and diesel fuel. LD50 orally in mice, guinea pig, rabbit: 352; 905; 95 mg/kg; orally in male, female rats: 175 ±33; 89 ±14; LC50 inhalation in rat: 0.22 mg/l (Stara).

Use

Antiknock fuel additive; dopant for Mn.