Hydrido complexes manganese

Hydrido complexes, gold-osmium, 27 209 iridium, 26 117, 27 19 iron, 26 244, 27 168 iron-tungsten, 26 336 manganese, 26 226 mercury-molybdenum-ruthenium,... 

As regards the similarity with simple coordination of two-electron ligands, it is of interest to discuss the oxidative addition of silicon hybrid to methyl cyclopentadienyl-manganese carbonyl and the nature of the bonding in the adduct. Hydrido silyl-manganese complexes were first prepared by Jetz and Graham according to... 

The easy reductive elimination process does not seem to arise from a particular lability of the hydrido silyl-manganese complex. It is stable in solution. Moreover, functionalized... 

SCHEME 11. Reactions of optically active hydrido silyl-manganese complex... 

The particular chemical behaviour of the hydrido silyl-manganese complex, which contrasts sharply with that of hydrido silyl-iron complexes56,77, has been interpreted in terms of a bonding interaction between hydrido and silyl ligands. 

FIGURE 4. Representation of hydrido silyl-manganese complexes... 

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. 

F,MnO SC6, Manganese( I), pentacarbonyl-(trifluoromethanesulfonato)-, 26 114 F,0 CH, Acetic acid, trifluoro-tungsten complex, 26 222 F,02C,H, Acetic acid, trifluoro-ruthenium complex, 26 254 FjOjSCH, Methanesulfonic acid, trifluoro-iridium, manganese and rhenium complexes, 26 114, 115, 120 platinum complex, 26 126 F304PtSC,4H,5, Platinum(II), hydrido-(methanol)bis(triethylphosphine)-Irans-, trifluoromethanesulfonate,... 

PRuC.mHjj, Ruthenium(II), [2-(diphenyl-phosphino)phenyl-C P](r) -hexamethyl-benzene)hydrido-, 36 182 PSC2H7, Phosphine sulfide dimethyl- and manganese complex, 26 162... 

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... 

The same allene analog 119 was obtained from the reaction of hydrido manganese complex [ Cp,Mn(CO)2 2H] Na+ with PbCl2520 521. Treatment of 119 with excess of... 

Additives are also used to improve the solubility of halide donors [382, 383]. Metal(II) halides such as magnesium chloride, calcium chloride, barium chloride, manganese chloride, zinc chloride and copper chloride etc. are used as halide sources. In order to increase the solubility of the halides they are reacted with electron donors which have been previously described for the increase of solubility of Nd-components [338,339]. The number of catalyst components is further increased if two Al-compounds (alumoxane + aluminum (hydrido) alkyl) are used. In addition, a small amount of diene can also be present during the preformation of the different catalyst components as described by JSR. In some catalyst systems the total number of components reaches up to eight [338,339]. Such complex catalyst systems are also referred to in other JSR patents [384,385] (Sect. 2.2.6). 

The chemistry of the metal carbonyl hydrides and metal carbonylates remained the principal research topic for Hieber until the 1960s. He mentioned in his account [25], that it was a particular pleasure for him that in his laboratory the first hydrido carbonyl complexes of the manganese group, HMn(CO)5 and HRe(CO)5, were prepared by careful addition of concentrated phosphoric acid to solid samples of the sodium salts of the [M(CO)5] anions, giving the highly volatile hydrido derivatives in nearly quantitative yield [45, 46]. In contrast to HCo(CO)4 and its rhodium and iridium analogues, the pentacarbonyl hydrido compounds of manganese and rhenium are thermally remarkably stable, and in... 

Only the monometallic complexes, RCORh(CO)4, Rli4(CO)i2, Rh6(CO)i6, HMn(CO)5 and Mn2(CO)io, were observed during the reaction. In addition, the kinetic data is consistent with a unicyclic catalytic reaction mechanism (i.e. mononuclear intermediates, equations 7 and 8). Product formation is most probably due to interactions between a rhodium-acyl intermediate, for example, RCORh(CO)4, and a hydrido-manganese species ... 

Some insight into the mechanisms of the iodine-promoted carbonylation has been obtained by radioactive tracer techniques [17] and low-temperature NMR spectroscopy [18]. The mechanism involves the formation of HI, which in a series of reactions forms with rhodium a hydrido iodo complex which reacts with ethylene to give an ethyl complex. Carbonylation and reductive elimination yield propionic acid iodide. The acid itself is then obtained after hydrolysis. The rate of carboxylation was reported to be accelerated by the addition of minor amounts of iron, cobalt, or manganese iodide [19]. The rhodium catalyst can be stabilized by triphenyl phosphite [20]. However, it is doubtful whether the ligand itself would meet the requirements of an industrial-scale process. 

To explain their results, Hart-Davies and Graham proposed to depict manganese complexes 172 in terms of resonance hybrids between representations 178 and 179 (261) (Figure 18). However, the possibility that the close Si-H distance is due to steric constraints has been raised by Bennett and Simpson (264). Steric effects favor a cis orientation of silyl and hydrido ligands and thus facilitate reactions involving reductive elimination pathways. 

Earlier, Herrmann et al. (1976 a, 1976 b) found that the mononuclear (pentacar-bonyl)(hydrido)manganese complex 10.74 forms a 10 1 mixture of the di- and trinuclear complexes 10.75 and 10.76 with diazomethane, if the reagents are mixed in THF at - 85 °C and the system is allowed to reach room temperature (10-34). In the same reaction with the analogous rhenium complex, only the binuclear complex... 

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