Manganese-nitrido complexes

Manganese(V) complexes of the Schiff base ligand salen and its derivatives have been the focus of intense study. These complexes have one additional ligand, either an 0x0, 0 , or a nitrido, group and much of the interest arises because these oxygen or nitrogen atoms are readily... 

In 1983, Groves demonstrated the stoichiometric aziridination of alkenes from a manganese-imido complex generated in situ from an isolable (porphyrin)man-ganese-nitrido intermediate (Scheme 1) [4]. This reactivity has recently been exploited with success by DuBois, Carreira and coworkers in the context of (salen)manganese-derived systems for the amination of enol ether derivatives (Scheme 2) [5,6,7,8]. Although not isolated, aziridine intermediates are probably involved in these reactions. 

Saltsman I, Goldberg I, Gross Z (2010) Water-soluble manganese(III) corroles and corresponding (nitrido)manganese(V) complexes. J Porphyr Phthalocyanines 14 615-620... 

In 1989, Volz reported the isolation of an iodosylbenzene complex of [(TDCPP) MnCl] from the reaction of the components at —78°C (Scheme 9) [35]. The crystalline compound could epoxidize olefins, oxygenate cyclohexane, and oxidize triphenylphosphine. Interestingly, reaction of this material with ammonia led to the formation of the manganese(V) nitrido complex [(TDCPP)Mn=Nj. In 1992, Volz reported details for related CgFsIO complexes [36]. 

Photooxidation of the metal center is not a commonly observed reaction with metalloporphyrins, but examples do exist. Both chromium(III) and manganese(III) porphyrins will undergo photooxidation reactions under appropriate conditions. Perchlorate amine-, oxides, and methyl viologen (MV " ) have been used as oxidants in these photoreactions, and photolysis of the corresponding azido complexes results in the formation of a nitrido complex where the metal ion has undergone a two-electron oxidation. Examples of such reactions are ... 

A number of nitrido manganese complexes have been reported. Most of these complexes are Mnv, with only one example reported for Mnvn. These complexes typically incorporate polydentate ligands thus, no examples could be found of simple halide or alkoxide nitrido manganese complexes. Since the original disclosure by Groves and co-workers that these could be utilized as nitrogen transfer reagents, they have received considerable attention [48,49]. ... 

Irradiation of manganese azides derived from Mn(III) porphyrin, cyclam, and polyamide complexes represents one of the earliest methods reported for the preparation of nitrido manganese complexes (Eq. (40)) [50], Additional methods have become available for the synthesis of manganese nitrides that utilize ammonia in combination with oxidants such as Cl2, PhIO, NaCIO, and NBS (Eq. (41)) [51-53]. Employing these methods, the manganese nitrides incorporating porphyrin, phath-locyanine, cyclam, salen, and bidentate Schiff base complexes have been documen-... 

The transfer of a nitrogen atom from a metal nitride to another metal complex is a process that works quite well with Mnv nitrides. Thus manganese nitrides derived from porphyrin or salen ligands participate in nitride transfer reaction to salen and porphyrin Mnm complexes to give new nitrido manganese products (Eq. (42) Chart 2) [55,56]. 

Asymmetric Nitrogen Transfer with Nitrido-manganese Complexes... 

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]. 

Finally it may be noted that N transfer from nitrido species such as salen or porphyrin complexes of manganese, e.g., porph Mnv=N, to organic substrates can occur. Examples are aziridation of cyclooctene or animation of silylenol ethers.167... 

Methanol, platinum complex, 26 135 tungsten complex, 26 45 Methyl, iridium complex, 26 118 manganese complex, 26 156 osmium complex, 27 206 rhenium complexes, 26 107 Methyl acetate, iron complex, 27 184 osmium complex, 27 204 Methyl benzoate, chromium complex, 26 32 Methylene, osmium complex, 27 206 Molybdate(l -), (acetato)pentacarbonyl-, M.-nitrido-bis(triphenylphosphorus) (I-h), 27 297... 

Golubkov G, Gross Z (2005) Nitrogen atom transfer between manganese complexes of salen, porphyrin, and corrole and characterization of a (nitrido)manganese(VI) corrole. J Am Chem... 

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