Nitrido manganese

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]. 

Although the nitrido manganese(V) porphyrin noted earlier was made in 1983, only recently has a comprehensive range of compounds without oxo groups been made.67... 

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... 

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

Treatment of the nitrido manganese(V) derivative of 5,10,15,20-tetra-mesitylporphyrin with trifluoroacetic anhydride in the presence of an excess of cyclooctene resulted in the transfer of the nitrogen atom to the olefin. Conversion of cyclooctene to the corresponding aziridine proceeded via nitrenoid Mn porphyrin intermediate. During this process the nitrido Mn(V) porphyrin was reduced to the trifluoroacetato Mn(III) porphyrin. 

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... 

These red compounds contain a Mn—N triple bond, are diamagnetic, five-coordinate and show considerable chemical stability. Thus while the isoelectronic oxochromium(IV) or oxomolyb-denum(IV) porphyrins behave, respectively, as weak oxidants and reductants, the corresponding manganese(V)nitrido species exhibits enhanced redox stability. [MnN(TPP)] and related porphyrin species were also independently prepared by the reaction of iodosylbenzene with [MnmX(por-phyrin)] (X = Cl, Br, OAc) in dichloromethane itt the presence of excess ammonia.758... 

One of the structural analyses refers to a porphodimethene macrocycle,759 which survived (12% yield) the reductive methylation of the analogous nitrido(octaethyl-porphyrin)manganese(V) species, illustrating the redox stability of such formally Mnv compounds.. 

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... 

The reaction of nitrido(5,10,15,20-tetramesity]porphyrinato) manganese(V) (TMPMn = N), obtained by photolysis of the azide (TMPMnN,) with excess trifluoroacetic anhydride, afforded, in situ, the trifluoroacetylimidomanganese(V) trifluoroacetate which reacted with cyclooctene to give the corresponding AT-trifluoroacetyl aziridine l97. 

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... 

Mn2NP3C3 H4o, Manganate(l-), p-(di-phenylphosphino)-bis(tetracarbonyl-, (Mn—Mn), p-nitrido-bis(triphenyl-phosphorus)(l -i-), 26 228 OKMn2N2C2oH, Manganese, p-(azodi-2,l-pheny lene-C, C, yV )octacar-... 

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. 

Cbz Cp DABCO DBU DDQ (DHQD)2CLB (DHQD)2PYR DMF DME DMPU DMSO Et Fmoc HMPA ia KHMDS LDA LiHMDS Me MEM Ms NaHMDS Ph Piv PMB Pr Py (saltmen)Mn(N) benzyloxy carbonyl p 5 -cyclopentadienyl l,4-diazabicyclo[2.2.2]octane l,8-diazabicyclo[5.4.0]undec-7-ene 2,3 -dichloro-5,6-dicyanobenzoquinone dihydroquinidinyl p-chlorobenzoale (see Chart 1) dihydroquinidinyl pyrimidine (see Chart 1) dimethylformamide dimethoxyethane l,3-dimethyl-3,4,5,6-tetrahydro-2(l//)-pyrimidinone dimethylsulfoxide ethyl 9-fluorenylmethoxy carbonyl hexamethylphosphoric triamide inverse addition potassium hexamethyldisilazide lithium diisopropylamide lithium hexamethyldisilazide methyl (2-methoxy ethoxy )methyl methanesulfonyl sodium hexamethyldisilazide phenyl pivaloyl p -methoxy benzyl propyl pyridine nitrido[A,A/-(l,l,2,2-tetramethyl) bis(salicylideneaminato)]manganese (see Chart 1)... 

Chromium and Manganese Oxo, Imido, and Nitrido Group Transfer Reagents... 

Mn (=0)TMP (28) was isolated and characterized 101). Infrared and Raman data have shown that the manganese-oxygen bond was unusually weak (i mi =o 574). The weakening of the Mn=0 rr-bond was ascribed to the high-spin electronic structure of 31 and the special nature of the resulting half-filled t2g orbital subset. Interestingly, an isoelectronic nitrido-iron(V) porphyrin recently prepared by low-temperature matrix photolysis of an iron(IIl) azide shows an unusually weak iron-nitrogen bond (876 cm ) 102). 

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