Pursuit of an Electron Deficient Titanium Nitride.

The nitride salt [(PN)Ti≡N{μ-K(OEt)}] () (PN = (-(2-PPr-4-methylphenyl)-2,4,6-MeCH) can be oxidized with two equiv of I or four equiv of ClCPh to produce the phosphinimide-halide complexes (NPN')(PN)Ti(X) (X = I (), Cl (); NPN' = N-(2-NPPr-4-methylphenyl)-2,4,6-MeCH), respectively. In the case of , H was found to be one of the other products; whereas, HCPh and Gomberg's dimer were observed upon the formation of . Independent studies suggest that the oxidation of could imply the formation of the transient nitridyl species [(PN)Ti(≡N•)] (), which can either oxidize the proximal phosphine atom to produce the Ti(III) intermediate [(NPN')(PN)Ti] () or, alternatively, engage in H atom abstraction to form the parent imido (PN)Ti≡NH ().

Electrocatalytic Azide Oxidation Mediated by a Rh(PNP) Pincer Complex.

One-electron oxidation of the rhodium(I) azido complex [Rh(N )(PNP)] (5), bearing the neutral, pyridine-based PNP ligand 2,6-bis(di-tert-butylphosphinomethyl)pyridine, leads to instantaneous and selective formation of the mononuclear rhodium(I) dinitrogen complex [Rh(N )(PNP)] (9 ). Interestingly, complex 5 also acts as a catalyst for electrochemical N oxidation (E ≈-0.23 V vs.

Electronic Structure and Magnetic Anisotropy of an Unsaturated Cyclopentadienyl Iron(I) Complex with 15 Valence Electrons.

The 15 valence-electron iron(I) complex [Cp Fe(IiPr Me )] (1, Cp =C (C H -4-Et) ; IiPr Me =1,3-diisopropyl-4,5-dimethylimidazolin-2-ylidene) was synthesized in high yield from the Fe precursor [Cp Fe(μ-Br)] . Fe Mössbauer and EPR spectroscopic data, magnetic measurements, and ab initio ligand-field calculations indicate an S= 3/2 ground state with a large negative zero-field splitting. As a consequence, 1 features magnetic anisotropy with an effective spin-reversal barrier of U =64 cm .

Selective P Activation by a Highly Reduced Cobaltate: Synthesis of Dicobalt Tetraphosphido Complexes.

Although the chemistry of transition metal polyphosphide anions has attracted significant attention, there are few reports of studies in which such species have been synthesized directly from white phosphorus. [K(OEt ) {Co(BIAN)(cod)}] (1, BIAN=1,2-bis(2,6-diisopropylphenylimino)acenaphthene, cod=1,5-cyclooctadiene), which is readily prepared by ligand exchange from [K(thf) {Co(cod) }], reacts with P to afford [{K(thf)} {(BIAN)Co} (μ-η :η -P )] (2 a) in 61 % yield (isolated product). [{K(OEt )} {(BIAN)Co} (μ-η :η -P )] (2 b) and [K([18]crown-6)(MeCN)] [{(BIAN)Co} (μ-η :η -P )] (2 c) were obtained by recrystallizing 2 a from diethyl ether and acetonitrile (and using [18]crown-6 in case of 2 c).

Porphyrin Cobalt(III) "Nitrene Radical" Reactivity; Hydrogen Atom Transfer from Ortho-YH Substituents to the Nitrene Moiety of Cobalt-Bound Aryl Nitrene Intermediates (Y = O, NH).

In the field of cobalt(II) porphyrin-catalyzed metallo-radical reactions, organic azides have emerged as successful nitrene transfer reagents. In the pursuit of employing ortho-YH substituted (Y = O, NH) aryl azides in Co(II) porphyrin-catalyzed nitrene transfer reactions, unexpected hydrogen atom transfer (HAT) from the OH or NH₂ group in the ortho-position to the nitrene moiety of the key radical-intermediate was observed. This leads to formation of reactive ortho-iminoquinonoid (Y = O) and phenylene diimine (Y = NH) species.

Photolytic N2 splitting: a road to sustainable NH3 production?

The split up: Recent advances in photochemical dinitrogen splitting have been achieved. Demonstration of the reversibility of the N2 splitting and ammonia formation from a nitride has advanced the field of N2 fixation using a synthetic homogeneous system.

An isolated nitridyl radical-bridged {Rh(N·)Rh} complex.

Photochemical activation of [(PNNH)Rh(N3)] (PNNH = 6-di-(tert-butyl)phosphinomethyl-2,2'-bipyridine) complex 2 produced the paramagnetic (S = 1/2), [(PNN)Rh=N(·)-Rh(PNN)] complex 3 (PNN(-) = methylene-deprotonated PNNH), which could be crystallographically characterized. Spectroscopic investigation of 3 indicates a predominant nitridyl radical ((·)N(2-)) character, which was confirmed computationally. Complex 3 reacts selectively with CO, producing two equivalents of [(PNN)Rh(I)(CO)] complex 4, presumably by nitridyl radical N,N-coupling.