Nitrido species

Photolysis of the monoazido species [Mn L (acac)L]BPh4 (where L is 1,4,7-triazacyclononane, is its N-methylated derivative, and acac is pentane-2,4-dionate) in the solid state has been demonstrated to yield the six-coordinate nitrido species [Mn L(N)(acac)]BPh4. ... 

The values for the corresponding chloro complexes are +0.21 V and +1.84V, respectively. It was concluded that these dramatic differences are a result of greater interaction of the nitrido ligand with the technetium center in comparison to the oxo ligand. This leads to stronger destabilization of the axial ligands for the nitrido species and hence to an increased susceptibility for an oxidation process. Thus, the oxidation is easier for [TcNCU]" than for [TcOC ], and even a... 

No nitrido complexes of ruthenium(VIII) have been isolated. For osmium, the only well-established osmium(VIII) nitrido species is [0s(0)3(N)] , which has been well documented in CCC (1987). A number of heterometallic complexes formed by the interaction of [0s(0)3(N)] with a second metal center have been reported. In these complexes, the [0s(0)3(N)] ion acts as a... 

Two reviews devoted to this topic have appeared.131,132 It is an area still in its infancy but one which shows considerable promise for the future. To date, emphasis has been placed largely on synthetic methods but increasingly the reactivity of these multimetal systems has come under investigation. In particular the ease by which NO undergoes bond cleavage to produce nitrido species has enabled workers in the field to provide a better understanding of the Haber process. 

Petrenko T, DeBeer George S, Aliaga-Alcalde N, et al. Characterization of a genuine iron (V)-nitrido species by nuclear resonant vibrational spectroscopy coupled to density functional calculations. J Am Chem Soc. 2007 129 11053-60. 

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... 

Ruthenium(V), (VI), (VII), (VIII) (d3, d2, d, d°) These complexes are restricted to halo, oxo and nitrido species such as [RuNClJ-, [RuNC15]2 and [Ru04]2-, . Oxo complexes of ruthenium have been used as oxidation catalysts. 

No mononuclear osmium(IV) nitrido complexes have been established, but /i-nitrido species containing a linear Os—N—Os unit are known, and there are trinuclear species of osmium(IV) and of mixed oxidation state containing Os—N—Os—N—Os units. The existence of both types is predictable from bonding considerations. They are dealt with on p. 564. 

The diamagnetic /i-nitrido species Os2N(S2CNEt2)5 formally contains osmium(IV) and is considered on p. 563. For /ac-Os(PMe2Ph)3(S2CNMe2)(OEt), see p. 596. 

Although the mechanism of reduction of N2 in biological systems is by no means clear, the reactions of coordinated N2 in simple systems are reasonably well understood. The principal types of reaction sequence involve hydrazido, imido, and nitrido species (see Section 9-19). 

The splitting of N2 to give nitrido species was noted in Section 9-3. 

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... 

D-7 Nitrido and Nitrene (imido) Complexes Nitrido Species... 

Osmium nitrido species may be luminescent and have other photophysical and chemical properties and Os 1 compounds such as [0s(N)(bipy)Cl2(H20)]+ and [Os(N)(NH3)4]3+ have been studied in some detail.116 Interaction of [Os(N)C14] and... 

Reaction of [ Mo(porph) 2] with MesSiNs affords the nitrido species [Mo Nfporph)] which had a sqnare-pyramidal structure (4uo n = 1-63 A). The nitrido gronp was reactive, treatment of [MoN(porph)J with H+, Sg, and RI affording [Mo(NH)(porph)]+, [Mo(NS)(porph)], and [Mo(NR)(porph)]I, respectively. Related phthalocyanine complexes, [MoN(pc)] were also described. 

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