2-Methylcyclopentadienyl manganese

Methylcyclopentadienyl manganese tricarbonyl that has been suggested as a fuel additive is decomposed primarily by photolysis in aqueous medium. This resulted in the formation of methylcyclopentadiene that may plausibly be presumed to polymerize, and a manganese carbonyl that decomposed to Mn304 (Garrison et al. 1995). 

Chlorinated aromatic hydrocarbons Volatile methyl-silicon compounds Methylcyclopentadienyl manganese (CO)3... 

Garrison AW, MG Cippolone, NL Wolfe, RR Swank (1995) Environmental fate of methylcyclopentadienyl manganese tricarbonyl. Environ Toxicol Chem 14 1859-1864. 

Ressler T, J Wong, J Roos, IL Smith (2000) Quantitative speciation of Mn-bearing particulates emitted from autos burning (methylcyclopentadienyl)manganese tricarbonyl-added gasolines using XANES spectroscopy. Environ Sci Technol 34 950-958. 

Abbott PJ Methylcyclopentadienyl manganese tricarbonyl (MMT) in petrol the toxicological issues. Sci Total Environ 67 247-255, 1987... 

Clay RJ, Morris JB Comparative pneumotoxicity of cyclopentadienyl manganese tricarbonyl and methylcyclopentadienyl manganese tricarbonyl. Toxicol Appl Pharmacol 98 434—443, 1989... 

Toxicology. 2-Methylcyclopentadienyl manganese tricarbonyl (MMT) causes central nervous system effects and liver, kidney, and pulmonary damage in animals. 

The 2003 ACGIH threshold limit valuetime-weighted average (TLV-TWA) for 2-methylcyclopentadienyl manganese tricarbonyl is 0.2 mg/m as Mn, with a notation for skin absorption. 

Komura J, Sakamoto M Disposition, behavior, and toxicity of methylcyclopentadienyl manganese tricarbonyl in the mouse. Arch Environ Contam Toxicol IhAlh-M5, 1992... 

Cox DN, Traiger GJ, Jacober SP, Hanzlik RP Comparison of the toxicity of methylcyclopentadienyl manganese tricarbonyl with that of its two major metabolites. Environ Lett 39 1-5, 1987... 

For the past several years other additives have been tried. Methylcyclopentadienyl manganese tricarbonyl (MMT) has been used in... 

Scheme 3.11 Reaction of cycloheptatrienyl-(methylcyclopentadienyl)manganese with bis(trimethylstannyl)-butadiyne and bis(dimethylphosphino)ethane.

The desire to improve the octane rating of fuels after the refining process without the use of lead has intensified a search for other "antiknock compounds. For example, compounds of Mn (5) and Ce (9) have been explored for this purpose. Methylcyclopentadienyl manganese tricarbonyl, in particular, is already being marketed for octane improvement. At a recommended level of 0.125 g Mn/gal, 200-500 g of Mn can be expected to pass the exhaust system within 50,000 miles. The main criteria in accepting such fuel additives are their compatibility with catalytic systems, and, of course, health-safety considerations. 

Methylcyclopentadienyl manganese tricarbonyl (MMT) is an additive in many commercial unleaded gasolines, and thus its potential effect on catalyst performance is an important consideration. It was reported by Faggan et al. 8) that MMT at a recommended level of 0.125 g Mn/gal shows no adverse effect on emissions, when compared to unleaded gasoline, in tests on cars operated on the 50,000-mile EPA certification schedule. These findings have been confirmed by a number of unpublished test reports from several industrial laboratories. In fact, it is indicated that some of the manganese deposits can aid catalytically in the removal of CO, and possibly to some extent also of hydrocarbons. The consequence of such a catalytic effect of Mn has still to be explored. 

Aue et al. [691] used gas chromatography with electron capture detection to determine methylcyclopentadienyl manganese tricaibonyl in non saline waters. 

The use of cyclopentadienyl-carbon monoxide compounds of Mn, as anti-knock agents in fuels, has been known for some time. In recent years the use of methylcyclopentadienyl manganese tricarbonyl (MMT) as an antiknock agent for gasoline has become more widespread, due to the decline in use of Pb alkyl compounds. 

Until the advent of the methylene chloride-water solvent system the less reactive acid chlorides could be used in the aqueous method but the more reactive acid chlorides required the anhydrous hydrogen cyanide method. This latter method is still sometimes used - and in fact has been used with quinoline and the 2- and 3-carboxylic acid chlorides of methylcyclopentadienyl manganese tricarbonyl."... 

Chau, Y.K., Yang, F., Brown, M. Determination of methylcyclopentadienyl-manganese tricarbonyl (MMT) in gasoline and environmental samples by gas chromatography with helium microwave plasma atomic emission detection. Appl. Organomet. Chem. 11, 31-37 (1997)... 

METHYL-l-CYCLOPENTADEC-ANONE see MIT625 METHYLCYCLOPENTADIENYL MANGANESE TRICARBONYL see MAV750... 

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