Manganese carbonyl derivatives

This reaction is used with different boron halides and manganese carbonyl derivates in 12 at RT to yield B—Mn compounds (Table 1). 

Group VIIA (Mn, Tc. Re). A number of mononuclear manganese carbonyl derivatives have been y- irradiated and examined by e.s.r. spectroscopy. The motivation behind much of this effort was the search for the elusive radical Mn(CO)s. The e.s.r. spectrum of this species is now firmly (35-37) established (Figure 4), although there is still some suggestion that the true "naked Mn(CO)s has yet to be observed (37). 

The cationic manganese carbonyl derivative Mn(CO)4(phen)+ has been isolated as the Co(CO)4 and Mn(CO)5 salts (445) and the technetium derivatives Tc(CO)s(phen)X are also known. The color is a function of the halogen X, changing from colorless (X = Cl), through bright brown (X = Br), to brown (X = I) (374). The reaction of bipyridyl with pentacarbonyliron induces disproportionation (375) this can also occur when bis(l,3-cyclohexadiene)tetracarbonyldicobalt is the reactant. However, [L2(CO)4Co2] has been prepared 62). 

Caution. Because of the toxicity of manganese carbonyl derivatives, the preparation must be carried out in a well-ventilated hood. Acetonitrile is also toxic. 

Complexes of manganese with the 1,1-dithiolates have been restricted to the (PrSN)3[Mn(i-mnt)3] complex (112) and nitrosyl or carbonyl derivatives, e.g., [7i--CpMn(NO)(S2C==X)] (X = C(CN)C02Et, C(CN)C0NH2, NCN, C(CN)2, or (HNO2) (110, 204, 205). These complexes undergo electrochemical, one-electron oxidations and reductions to afford the neutral or dianionic species. 

Reaction of the manganese and rhenium carbonyls, M2(CO)10, with Ru3(CO)12 or Os3(CO)12 in a 3 1 ratio yields the products [M(CO)5]2M (CO)4, with M = Re or Mn, M = Ru or Os. These are considered to be linear trinuclear metal systems. The only other trinuclear carbonyl derivative isolated is OsCo2(CO)n, obtained as one of a number of compounds from the reaction of Co2(CO)8 with H2Os(CO)4. No structural data are available for this compound (241). 

The first six entries in this section of Table X (entries 93-98) relate to attempted insertion reactions of fluoroalkenes or fluoroalkynes into Si-Mn or Si-Fe bonds. Even in the successful cases, yields are generally low, and in some instances (e.g., entry 94) MesSiF is lost from the insertion product to leave a fluoroalkenyl manganese carbonyl. In the case of the iron hydrido compound in entry 98, there is formal loss of hydrogen to give the binuclear derivative [CljSiFelCO). ... 

Following our early studies (89, 90), we have recently investigated derivatives of manganese carbonyl obtained from reactions between Mn(CO)5X (X usually Br) and organic sulfur ligands (93). Manganese carbonyl chelate complexes are formed in which sulfur is covalently bonded to manganese, or forms a coordinate bond as an electron donor. 

Derivation Reaction of methylcyclopentadiene with manganese carbonyl. 

Examples of the promotion of orthometallation by oxygen donors are limited to side chains containing ketonic and amide carbonyl groups. The use of ketone oxygen as the donor atom to promote orthometallation has been reported only for manganese and rhenium carbonyl derivatives ... 

One class of compoimds that frequently does obey the EAN rule comprises the metal earbonyls and their derivatives. By using this rule it is possible to prediet aeeurately eoordination numbers of the simplest carbonyls and also predict whether the eompounds can exist as monomers. For example, the EAN is 36 for the metals in the compounds Ni(CO)4, Fe(CO)5, Fe(CO)4Cl2, Mn(CO)5Br, CoNO(CO)3, and Fe(NO)2(CO)2. To estimate the EAN in these systems, it is convenient to say that, CO, Cl, and Br contribute two electrons and NO, three electrons. Manganese carbonyl has the formula (CO)sMn—Mn(CO)s which is the simplest formula possible if each Mn is to have an EAN of 36. 

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