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Manganese complexes amines

At the same time the bond angles (C—N—C) at the N7 position vary from 112 (-fp3 as expected for an amine ligand) in the manganese complex (where repulsion is least) up to a maximum value of 120 in the iron complex with maximum repulsions. The tertiary amine nitrogen atom (N7) corresponds to a three-ribbed umbrella that has been inverted by the wind (the handle is the lone pair directed at the metal). As the a, and If levels fill, the repulsions increase, the metal-nitrogen distance increases, and the umbrella begins to flatten ... [Pg.795]

Very recently, Jprgensen s group reported the preparation of some chiral nitrido-manganese complexes, which closely resemble those synthesized by the authors group, and the application to asymmetric amination of silyl enol ethers with the chiral complexes using Carreira s method [35], These results were very similar to those of the authors [22]. [Pg.192]

Jacobsen and co-workers have devised highly enan-tiospecific manganese complexes for epoxidations of olefins with sodium hypochlorite.94 Peracids and amine N-oxides can also be used as oxidants. A typical catalyst is shown in 10.43 ... [Pg.307]

The amidation of saturated C—H bonds can be effectively catalyzed by ruthenium or manganese complexes. Unfunctionalized hydrocarbons, such as adamantane, cyclohexene, ethylbenzene, cumene, indane, tetralin, diphenylmethane and others, are selectively amidated with PhINTs in the presence of ruthenium or manganese porphyrins or the ruthenium cyclic amine complexes to afford N-substituted sulfonamides in 80-93% yields with high selectivity [807]. The enantioselective amidation of a C—H bond can be catalyzed by chiral (salen)manganese(III) complexes (e.g., 660) [808], or by chiral ruthenium(II) and manganese(III) porphyrins (Scheme 3.264) [809]. [Pg.256]

Mn2(H2P202)2) is the stable product in the potentiometric deterrnination of manganese. Manganese(III) does not coordinate with amines or nitro complexes, but it does make manganicyanides of the types M2(Mn(CN)g) and M2(Mn(CN) (OH)), which are similar to the ferricyanides. The K", Na", LC and manganicyanides have been prepared and slowly hydroly2e in water to MnO(OH). [Pg.507]

Another situation is observed when salts or transition metal complexes are added to an alcohol (primary or secondary) or alkylamine subjected to oxidation in this case, a prolonged retardation of the initiated oxidation occurs, owing to repeated chain termination. This was discovered for the first time in the study of cyclohexanol oxidation in the presence of copper salt [49]. Copper and manganese ions also exert an inhibiting effect on the initiated oxidation of 1,2-cyclohexadiene [12], aliphatic amines [19], and 1,2-disubstituted ethenes [13]. This is accounted for, first, by the dual redox nature of the peroxyl radicals H02, >C(0H)02 and >C(NHR)02 , and, second, for the ability of ions and complexes of transition metals to accept and release an electron when they are in an higher- and lower-valence state. [Pg.586]

The XPS results for cobalt at pH 4, particularly the Co 2p splitting (15 eV) and the absence of shake-up satellite structure, are indicative of cobalt(III). However, the N(amine)/Co atomic ratio of 2.7 indicates that some ammonia ligands have been displaced. Since it is known (22) that hydrolysis rates for cobalt(III) complexes are very slow, the presence of cobalt with a low number of coordinated amines, suggests that hydrolysis is induced via an interaction with the birnessite surface. The cobalt to manganese ratios for bulk and surface measurements are equivalent within experimental error, a result which is consistent with a reaction process occurring primarily at the surface. It is... [Pg.510]

Clearly an unambiguous examination of the chemical nature of sorbed complexes using SIMS in these measurements is complicated by the presence of manganese and manganese-cobalt containing ions in the spectra. The greater relative ion intensities and the intensity distribution differences for the pH 10 sample compared to the pH 7 material, may arise due to the presence of different surface amine species. Alternatively, the difference may be related to different secondary ion formation processes for sorbed species. [Pg.519]

It is quite often possible to prepare hydroxypyridinone complexes directly by one-pot synthesis from the appropriate hydroxypyranone, amine, and metal salt 90-92). They can also be prepared by reacting complexes such as P-diketonates with hydroxypyridinones (see e.g., Ce, Mo later). Several maltolate complexes, of stoichiometry ML2, ML3, ML4, or MOL2, have been prepared by electrochemical oxidation of the appropriate metal anode, M — a first-row d-block metal (Ti, V, Cr, Mn, Fe, Co, Ni), In, Zr, or Hf, in a solution of maltol in organic solvent mixtures 92). Preparations of, e.g., manganese(III), vanadium(III), or vanadium(V) complexes generally involve oxidation... [Pg.178]

Mn(acac)3 reacts with ethylenediamine (L2) or other primary amines (L) to yield [Mn"(acac)2L2], which can also be prepared by the reaction of the amine or diamine with [Mn(acac)2(H20)2]. Allylamine reacts with [Mn(acac)2-(H20)2] in ether to give a second complex, [Mn(acac)2(H2NCH2==CH2)]2 which is dimeric both in the solid and vapour phases. This is the First example of a dinuclear manganese(ii) acetylacetonate complex. Thermodynamic data have been reported for the manganese(ii)-acetylacetone system in propan-1-ol-water. ... [Pg.190]


See other pages where Manganese complexes amines is mentioned: [Pg.240]    [Pg.385]    [Pg.536]    [Pg.536]    [Pg.776]    [Pg.177]    [Pg.16]    [Pg.2516]    [Pg.85]    [Pg.507]    [Pg.2515]    [Pg.66]    [Pg.46]    [Pg.51]    [Pg.374]    [Pg.393]    [Pg.404]    [Pg.222]    [Pg.507]    [Pg.86]    [Pg.272]    [Pg.31]    [Pg.248]    [Pg.260]    [Pg.293]    [Pg.134]    [Pg.378]    [Pg.156]    [Pg.159]    [Pg.1025]    [Pg.279]    [Pg.314]    [Pg.436]    [Pg.441]    [Pg.47]    [Pg.510]   
See also in sourсe #XX -- [ Pg.16 ]

See also in sourсe #XX -- [ Pg.4 , Pg.16 ]




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