Cyclopentadienylmanganese tricarbonyls

A recently marketed fuel additive is MMT (methyl cyclopentadienylmanganese tricarbonyl). MMT was first developed by the Ethyl Corporation in 1957 as an octane enhancing agent and has experienced a growth in demand in the 1990s. MMT was Ethyl Corporation s first major new antiknock compound since TEL. 

Nesmeyanov et al.564 have measured the rates of deuteration of benzene and cyclopentadienylmanganese tricarbonyl by deuterated sulphuric acid-trifluoro-... 

A series of studies of cyclopentadienylmanganese tricarbonyl and related compounds has provided interesting results. As with the chromium compound mentioned above, it was found that carbonyl-rich compounds are formed in yields comparable to the retention. In these compounds, however, the yield of bi-nuclear Mn2(CO)io is not high, but mononuclear—Mn(CO)s compounds are prominent. The results are sumarized in Table 12. 

Fig. 4. Annealing data for cyclopentadienylmanganese tricarbonyl, showing an initial rise and subsequent fall in the apparent retention ". Other data "" showed the retention not to have this maximum so that the extra must be an additional compound...

Several preparations of silylated cyclopentadienylmetal complexes involve the formation of a triorganosilylcyclopentadienyl anion (by treatment of a silylated cyclopentadiene with an alkali metal in tetrahy-drofuran or by metalation with n-butyllithium), followed by reaction with metal chlorides. This type of reaction has been used for the synthesis of silylated ferrocenes (41, 43, 58, 83, 84, 103, 107, 116, 135, 142, 171, 172), cobaltocenes (135), nickelocene (135), titanium cyclopen-tadienyls (46, 145), and cyclopentadienylmanganese tricarbonyl (30) [Eqs. (19) and (20)]. It is remarkable that Si—C5H6 bonds are not... 

In a similar manner, UV irradiation of (triphenylsilyl)phenylacetylene with cyclopentadienylmanganese tricarbonyl 121) and cyclopentadienyl-niobium tetracarbonyl 122) results in elimination of carbon monoxide and formation of monodentate acetylene complexes (R = Ph) ... 

Still other 7r-cyclopentadienyl-metal compounds have been shown to undergo acylation. The successful acylation of cyclopentadienylmanganese tricarbonyl has opened up yet another interesting aromatic-type system for exploration (9, 10, 11, 13, 20, 45, 99). An example of this type concerns the benzoylation of methyl-cyclopen tadienylmanganese tricarbonyl (XII) (10, 45). Both l-methyl-2-ben-zoylcyclopentadienylmanganese tricarbonyl (XIII) and the corresponding 1,3-isomer (XIV) are readily obtained. 

A second synthetic technique has employed either pyridine or dioxane adducts of sulfur trioxide as sulfonating agents. Both ferrocene and ferrocenecarboxylic acid have been sulfonated in this manner (61, 72). Cyclopentadienylmanganese tricarbonyl is also readily sulfonated (10). 

The sulfonic acids of these metallocenes can be converted to sulfonyl chlorides, sulfonamides, etc., by appropriate reagents. Reduction of ferrocene-sulfonyl chloride by lithium aluminum hydride produces the rapidly oxidized ferrocenethiol in quantitative yield (43). Both the sulfonic acid of cyclopentadienylmanganese tricarbonyl and the corresponding sulfinic acid (obtained by sodium sulfite reduction of the sulfonic acid) have been converted to sulfones (10). 

BORONCOMPOUNDS - BORON HYDRIDES, HETEROBORANES AND THEIR METALLA DERIVATIVES] (Vol 4) Cyclopentadienylmanganese tricarbonyl [12079-65-1]... 

It is well known that certain transition metal organometallic complexes, such as ferrocene, cymantrene (cyclopentadienylmanganese tricarbonyl) and butadieneiron tricarbonyl, and to a lesser extent, benzenechromium tricarbonyl, form organic derivatives and have an extensive derivative chemistry of their own. The parent complexes have already been discussed there follows a summary of the main features observed in the mass spectra of their organic derivatives (Table II, at the end of this section). 

Aza analogs of cyclopentadienylmanganese tricarbonyl have also been prepared.158 160,162 Application of this sequence to pyrazole, imidazole, and 1,2,4-triazole, however, led not to aza analogs but to coordination polymers.168 A mixed manganese and chromium carbonyl complex of 2-benzylpyrrole has been prepared.163a... 

Fischer, Geiss, and others showed that cyclopentadienylmanganese tricarbonyl (CTM) possessed an extremely aromatic ring. We thought it useful to apply the reactions discovered by us for ferrocene to this molecule and to its rhenium analog (CTR). We succeeded in obtaining the compounds through the reaction (360 363)... 

Attempted photopinacolization of acyl-cyclopentadienylmanganese tricarbonyl with isopropanol caused decomposition 122>. 

Synonyms/Trade Names Cyclopentadienylmanganese tricarbonyl, Cyclopentadienyl tricarbonyl manganese, MCT... 

Simple reactions on the substituents can also be performed without destroying the complexes. Thus the aldehyde (CII R=CHO) undergoes borohydride reduction to the alcohol (CII R=CH20H), silver oxide oxidation to the acid (CII R=COOH), and adds methyl magnesium bromide to give the secondary alcohol (CII R=CHOHMe) after hydrolysis. The NMR spectra are consistent with their formulation as (CII) (see Section V, D). The complex (XVIII) thus behaves analogously to ferrocene and cyclopentadienylmanganese tricarbonyl. 

Olefins which undergo this reaction are 1-butene, 2-butene, isobutylene, a mixture of pentene isomers, diisobutylene, and tetrapropylene. Coffield et al. 82, 83) have shown that acetylene and manganese pentacarbonyl under 600 psi and at 150° C give l,2-(propenylene)cyclopentadienylmanganese tricarbonyl. The conditions of this synthesis are similar to those described by Reppe 84) for the reaction of acetylene with other metal carbonyls to form iT-bonded complexes. 

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