Manganese carbonyl, Mns

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 Mn atom has 25 electrons. Adding five carbonyl groups would raise the number to 35, leaving the atom one electron short of the krypton configuration. If the single unpaired electron on one manganese atom is then allowed to pair up with an unpaired electron on another to form a metal-metal bond, we have the formula (CO)5Mn-Mn(CO)5 or [Mn(CO)5]2, which is the formula for a manganese carbonyl that obeys the EAN rule. 

Herrmann and coworkers183 reported a series of Cp-manganese carbonyl complexes which bind Ge, Sn and Pb as central atoms linearly coordinated in clusters, to two Mn atoms in one series and trigonal-planar coordinated to three Mn atoms in another series 8 and 9. The group 14 atoms are double-bonded to two Mn atoms in these compounds, or carry one double bond and two single bonds to three Mn atoms. Potentiometric measurements of these compounds show irreversible reductions and oxidation by CV. No products could be isolated from either reduction or oxidation. The exceptionally high oxidation potential of (/i-Pb) r/ -CsHs )Mn(CO)2]2 as compared to the apparently similar Sn compound is noteworthy (Table 15). 

Manganese carbonyl, Mn2(CO)io, when treated with tetracyclone at 140-150°, gives an air-sensitive product which on hydrolysis gives the T-cyclopentadienyl complex (LII) 215). Manganese carbonyl does not react with dimcthylacetylene in sunlight, but duroquinone was formed in a similar reaction of the alkyne with [Mn(CO)6] 1 155). Mn(—1) is iso-electronic with Fe(0), and it is suggested that the unstable quinone com-... 

Bromopentacarbonylmanganese, Mn(CO)5Br (1). This yellow metal carbonyl halide is obtained in 73% yield by reaction of manganese carbonyl with Br2 in CC14 at 40°.1... 

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. 

Brunner has continued his studies on optically active manganese carbonyl complexes and has reported that treatment of Mn(CO)5Br with ort/to-Me2NC6H4PPh2 (PN) yields two enantiomers of/ac-[Mn(CO)3(PN)Br], Treatment of this complex with carbon monoxide in the presence of A1C13 produces the cation [Mn(CO)4(PN)] +, which was isolated as its hexafluorophosphated salt. Addition of menthoxide anions to the manganese carbonyl cation yields the diastereoisomers of Mn(CO)3(PN) (CO2C30H 9) however, these could not be separated due to their instability. Reaction of Mn(CO)5Br with the Schiff base NN (1) leads to formation of two isomers of... 

Under a nitrogen atmosphere 85 % phosphoric acid is added to the green solution, which changes first to purple subsequently the product precipitates as an orange-red solid. It is separated by filtration, washed with water until the washings are neutral, and dried in vacuo. Any unreacted manganese carbonyl may be removed by sublimation under reduced pressure at room temperature (1 mm./20°C.). The pure compound is then obtained as deep orange-red crystals by sublimation (1 mm./ 60°C.). The yield is 0.3-0.35 g. (64-74%). Anal. Found C, 28.6 H, 0.79 O, 37.7 Mn, 32.1. Calcd. for H Mn,(CO)12 C, 28.60 H, 0.56 O, 38.10 Mn, 32.70. 

We noted, however, that manganese carbonyl [61-63] [Mn2(CO)i0] (Amax 340 nm, OMn-Mn —> may be photolyzed without any sensitizer, leading... 

The manganese carbonyl disulfide complex (12) inserts various metal fragments into the S-S bond (Scheme 8). On the other hand, Me2S inserts into the Mn-Mn bond and tertiary phosphines substitute CO ligands. Heterobimetallic disulfides and diselenides analogous to (12) have been... 

The anionic manganese carbonyl complexes [Mn(CO)4(NCS)2]" (729) and [Mn2(CO)e(CNS)4] " (278) are known, the latter containing both bridging—NCS—and terminal—NCS groups (278) [Re(CO)3(NCS)3] is also known (278, 280). However, the most interesting compounds in this category are those prepared by Wojcicki and Farona (279, 280), which are listed in Table XXIV. 

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