Manganese complexation

The most important low-spin octahedral complex of Mn is the dark-red cyano complex, [Mn(CN)6] , which is produced when air is bubbled through an aqueous solution of Mn and CN . [MnXs] (X = F, Cl) are also known the chloro ion, at least when combined with the cation [bipyH2] +, is notable as an example of a square pyramidal manganese complex. 

When acetylthiophenes are subjected to orthomanganation, formation of the 2,3-, 103, and 3,4-, 104, metallocycles is observed [88JOM(349)197]. Complex 103 contains two coplanar live-membered heterocycles with octahedral manganese. Complex 104 is also planar. In both cases, substantial delocalization of the TT-electron density follows from the structural parameters. 

Grigg et al. have found that chiral cobalt and manganese complexes are capable of inducing enantioselectivity in 1,3-dipolar cycloaddition reactions of azomethine... 

Ordinary alkenes (without an allylic OH group) have been enantioselectively epoxidized with sodium hypochlorite (commercial bleach) and an optically active manganese-complex catalyst. Variations of this oxidation use a manganese-salen complex with various oxidizing agents, in what is called the Jacobsen-Katsuki... 

The reaction of Mn(CO)jBr and methyl isocyanide was also carried out (Table V) the products are analogous to those obtained from phenyl isocyanide and the manganese complex. 

Asymmetric epoxidation is another important area of activity, initially pioneered by Sharpless, using catalysts based on titanium tetraisoprop-oxide and either (+) or (—) dialkyl tartrate. The enantiomer formed depends on the tartrate used. Whilst this process has been widely used for the synthesis of complex carbohydrates it is limited to allylic alcohols, the hydroxyl group bonding the substrate to the catalyst. Jacobson catalysts (Formula 4.3) based on manganese complexes with chiral Shiff bases have been shown to be efficient in epoxidation of a wide range of alkenes. 

Baudry, M., Etienne, S., Bruce, A., Palucki, M., Jacobsen, E. and Malfroy, B. (1993). Salen-manganese complexes are superoxide dismutase-mimics. Biochem. Biophys. Res. Commun. 192, 964-968. 

Several catalysts that can effect enantioselective epoxidation of unfunctionalized alkenes have been developed, most notably manganese complexes of diimines derived from salicylaldehyde and chiral diamines (salens).62... 

The catalytic application of clays is related closely to their swelling properties. Appropriate swelling enables the reactant to enter the interlamellar region. The ion exchange is usually performed in aquatic media because the swelling of clays in organic solvents, and thus the expansion of the interlayer space, is limited and it makes it difficult for a bulky metal complex to penetrate between the layers. Nonaqueous intercalation of montmorillonite with a water-sensitive multinuclear manganese complex was achieved, however, with the use of nitromethane as solvent.139 The complex cation is intercalated parallel to the sheets. 

Martens, R. J. Swarthoff, T. (Unilever). Detergent Compositions Containing Dinuclear Manganese Complex as Bleach. Canadian Patent 2,083,661, 27 May, 1993. 

Manganese complexes, metal-complexed alcohol reduction, 25 Metal catalysts, organosilicon hydride mixtures, 5, 11... 

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