Hydride manganese

Indeed, if the new bonds are much stronger than the old, one can find an inverse kie. An instructive example of this is the reaction of a manganese hydride (deuteride) with alkenes 20... 

Recently proof has been reported for a heterometallic bimolecular formation of aldehyde from a manganese hydride and acylrhodium species [2], Phosphine free, rhodium carbonyl species show the same kinetics as the cobalt system, i.e. the hydrogenolysis of the acyl-metal bond is rate-determining. Addition of hydridomanganese pentacarbonyl led to an increase of the rate of the hydroformylation reaction. The second termination reaction that takes place according to the kinetics under the reaction conditions (10-60 bar, 25 °C) is reaction (3). The direct reaction with H2 takes place as well, but it is slower on a molar basis than the manganese hydride reaction. 

The second type involves cleavage of the silicon-manganese hydride occurring with inversion of configuration ... 

However, manganese hydrides undergo substitution at silicon without cleavage of the silicon-manganese bond Scheme 13) ... 

Substitution at silicon in an optically active silicon-manganese hydride has also been observed ... 

Lithium aluminum hydride exhibits the reverse reactivity toward manganese hydrides (cf. Sect. 3.6) ... 

The spectroscopic and kinetic data from this reaction indicated the existence of a long sought catalytic reaction topology, bimetallic catalytic binuclear elimination. The kinetic data provided a linear-bilinear form in organometallics [95]. One term represented the classic unicyclic rhodium catalyzed hydroformylation and the other represented the attack of manganese hydride carbonyl on an acyl rhodium tetracarbonyl species. A representation of the interconnected topology is shown in Figure 4.12. 

The orgarometallic chemistry of actinides. ignored in the early development of the field, is currently receiving a great deal of attention.1 7 In many instances the chemistry of this group of elements is unlike that of the transition metals. For example, it has been shown that a thorium hydride, in contrast to the manganese hydride shown above, does undergo CO insertion.138... 

Relaxation studies have also been used to estimate metal-hydrogen bond distances in rhenium and manganese hydride complexes (Gusev et al., 1993). 

An unusual reaction, with loss of a phenyl group from HSnPh3, occurs with some din-uclear manganese-hydride carbonyl complexes (equation 84)240. The chemistry outlined in the previous equations, involving elimination of H2, occurs in many regions of the periodic table and produces good yields of the metal-tin bonded complex. 

Metal Hydrides. Insertion of CO2 into the metal-hydrogen bond of ci3-HM(C0)HL (M = W, Cr L = CO, PMe, P(0Me>3) has been found to be an extremely facile process (17-19). This is in contrast with the inability of CO2 to insert into the metal-hydrogen bond of the analogous neutral manganese hydrides. Although the group 6 and group 7 hydrides are isoelectronic, they have rather different properties. The hydride in HMn(CO)s is in fact rather acidic with a pKa of a 7. 

Unlike many, if not most, transition metal hydrides which are relatively unstable and sensitive to air and moisture, the manganese hydride described here is completely stable in air. It serves as the starting material for the synthesis of a variety of derivatives in which the hydrogen atom is replaced by other atoms (or groups of atoms) directly bonded to manganese. Earlier methods of preparation involved the displacement of CO by bis(diphenyl-phosphino)ethane from the difficult to prepare and hard to handle HMn(CO)5 as well as from the decarboxylation of a postulated intermediate (diphos)Mn(CO)3COOH. Our preparation is a modification of a previously described procedure in which 1-propanol was used as reagent and as solvent. In addition to a much shorter reaction time, this procedure results in a pure, almost colorless product uncontaminated by an unknown dimer which frequently accompanies the hydride. ... 

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