Manganese decacarbonyl

Manganese decacarbonyl is used as an antiknock additive to gasohne and as a catalyst. 

Manganese decacarbonyl is prepared by the reduction of methylcyclopen-tadienyhnanganese tricarbonyl (MMT) with sodium in diglyme under carbon monoxide pressure. 

Manganese forms a decacarbonyl Mn2(CO)10 in which each manganese has the required share in 18 electrons to achieve the noble gas configuration. Reduction of this covalent compound with sodium amalgam gives the salt Na[Mn(CO)5], sodium pentacarbonyl-manganate ( - 1) in the ion Mn(CO)5 the noble gas structure is again attained. 

Nitroarenes are reduced to anilines (>85%) under the influence of metal carbonyl complexes. In a two-phase system, the complex hydridoiron complex [HFe,(CO)u]2-is produced from tri-iron dodecacarbonyl at the interface between the organic phase and the basic aqueous phase [7], The generation of the active hydridoiron complex is catalysed by a range of quaternary ammonium salts and an analogous hydrido-manganese complex is obtained from dimanganese decacarbonyl under similar conditions [8], Virtually no reduction occurs in the absence of the quaternary ammonium salt, and the reduction is also suppressed by the presence of carbon monoxide [9], In contrast, dicobalt octacarbonyl reacts with quaternary ammonium fluorides to form complexes which do not reduce nitroarenes. 

Finally, manganese carbonyl complexes also show potential for effecting interesting phase transfer catalyzed carbonylation reactions. Alkynes react with carbon monoxide and methyl iodide in methylene chloride, using 5N NaOH as the aqueous phase, benzyl-triethylammonium chloride as the phase transfer catalyst, and either bromopentacarbonylmanganese or dimanganese decacarbonyl to afford... 

Formula Mn2(CO)io MW 389.99 manganese in zero oxidation state. Synonyms dimanganese decacarbonyl manganese carbonyl... 

S04PC Hi , 2-Butenedioic acid, 2-(dimethyl-phosphinothioyl)-dimethyl ester, manganese complex, 26 163 SO Ci H i, Thiophenetetracarboyxlic acid, tetramethyl ester, 26 166 SO (,OsiC , Osmium, p,4-carbonylnona-car-bonyl-p,-thio-tri-, 26 305 SO ,OsiC 6H, Osmium, (p.-benzenethio-lato)-(decacarbonyl-p-hydrido-tri-, 26 304... 

Manganese pentacarbonyl is a free radical and spontaneously dimerizes to dimanganese decacarbonyl. Iron pentacarbonyl is a weak Lewis base and can be protonated by sulfuric acid, forming a metal-hydrogen bond. We will make extensive use of the isolobal... 

The decacarbonyls of manganese, technetium, and rhenium, of formula M2(CO)io, have terminal carbonyl groups and a metal-metal bond. The molecular symmetry is D d with the two M(CO)s fragments in a staggered conformation. The heterodinuclear decacarbonyl MnRe(CO)io is also known as obtained by the redox reaction of a rhenium pentacarbonyl halide with the pentacarbonylmanganate(-I) anion at room temperature (at 160 °C or higher, the heterodinuclear carbonyl tends to form the homodinuclear compounds with an equilibrium constant close to the statistical value ). The X-ray diffraction stndy of MnRe(CO)io has shown the Mn-Re distance of 2.909 A to be shorter than the sum of the covalent radii obtained from the homodinuclear compounds (Table 3). 

The carbonyl work was continued in the 1960s when the ferrocene studies (see below) were extending the organometallic chemistry of transition metals. Here I will mention manganese-rhenium decacarbonyl 213) obtained by us through the reation... 

Dimanganese decacarbonyl, which is prepared by the reduction of manganese(II) halide in the presence of carbon monoxide under pressure [3], is a yellow crystalline, air-stable solid soluble in organic solvents, which sublimes readily in vacuo at ca 50 °C. A single-crystal X-ray diffraction study showed that Mn2(CO)io possesses the structure as shown below. 

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