Chromium complexes dinitrogen

The chromium(O) complex (rans-[Cr(N2)2(dmpe)2] (2) has been prepared together with some incompletely characterized cis isomer from [CrCl2(dmpe)2] according to Scheme 8, which also shows that its reactions all involve displacement of dinitrogen. The trans dinitrogen ligands are linear, and the N—N bond distance (1.122 A) is normal. The IR spectrum of the trans isomer... 

There has been a report of bridged dinitrogen complexes of iron(III) and chromium(lll) complexes, formed by reaction of the metallo(IlI)porphyrinate triftate with [Re(N2)(PMe2Ph)4Cl] to make the Fe-N-N-Re or Cr-N-N-Re bridged complexes. The Fe complex has a magnetic moment of about 4.4 /u-b at room temperature, consistent with a S = 312,512 admixed spin state for the iron(lll), and a pyrrole-H shift of -3.23 ppm, consistent with the expected weak-fteld nature of the N2 ligand. The stracture shows a linear Fe-N-N-Re unit (Fe-Nl-N2 = 170°, Nl-N2-Re = 177°) with Fe-N bond length of 1.93 similar to that of the TPPFe -azide complex (1.953 A). 

In the Cr/N2 system binary dinitrogen complexes of chromium with from one to six co-ordinated Nj ligands per metal atom have been identified from their i.r. spectra in argon/diniirogen matrices at 10 K. The u.v. spectrum of is qualitatively similar... 

Chromium(I) complexes, 702 alkyl isocyanides, 704-709 aryl isocyanides, 704-709 2,2 -bipyridyl, 709 electrochemistry, 713 electronic spectra, 712 ESR spectra, 712 IR spectra, 712 magnetic properties, 710 synthesis, 709 cyanides, 703 fluorophosphine, 716 isocyanides crystallography, 708 electrochemistry, 709 spectroscopy, 708 synthesis, 707 1,10-phenanthroline, 709 electrochemistry, 713 electronic spectra, 712 ESR spectra, 712 IR spectra, 712 magnetic properties, 710 synthesis, 709 tertiary phosphines dinitrogen, 713 tris(bipyridyl)... 

The first report of a coordinated acetylacetone reaction was the bromination of the chromium(III) complex (equation 55). This was followed, more than 30 years later, by the nitration of copper(II) acetylacetonate with dinitrogen tetroxide (equation This result is... 

Few dinitrogen complexes of chromium are known. Complex 8 decomposes at 20 C with loss of both N2 and PMes. Treatment of complex 9 with acid produces small quantities of ammonia (7%) and hydrazine (1%). Reaction of the polynuclear complex 10 with water regenerates the starting rhenium complex tran5-[ReCl(N2)(PMe2Ph)4], and with dioxygen produces the cation [ReCl(N2)(PMe2Ph)4]. ... 

Vidyaratne I, Scott J, Gambarotta S, Budzelaar PHM. Dinitrogen activation, partial reduction, and formation of coordinated imide promoted by a chromium diiminepyridine complex. Inorg Chem. 2007 46 7040-7049. 

Mock MT, Chen S, O Hagan M, et al. Dinitrogen reduction by a chromium(O) complex supported by a 16-membered phosphoms macrocycle. J Am Chem Soc. 2013 135 11493-11496. 

Yuki M, Miyake Y, Nishibayashi Y. Preparation and protonation of mngsten- and molybdenum-dinitrogen complexes bearing bis(dialkylphosphinobenzene)chromiums as auxiliary hgands. Organometallics. 2009 28 5821-5827. 

Hydrazido(2 —) complexes are most prevalent within group VI although there are to date no reported hydrazido complexes of chromium. Representative examples of known structure are shown in Table 16. Sulfur coligands predominate reflecting the metal-sulfur coordination in nitrogenase and the participation of hydrazide ligands in dinitrogen chemistry. 

Dialkylhydrazido(2-) complexes have also been shown to be crucial intermediates in the electrochemical reduction of coordinated dinitrogen to substituted hydrazines (273). Finally a chromium(III) hydra-zido(2-) species has been proposed as an intermediate in the chro-mium(II) reduction of nitroamine (192). 

Chromium Trioxide. Forms unstable complex with chromium trioxide.2 Dinitrogen Tetroxide. Reacts violently with liquid dinitrogen tetroxide.5 Fluorine. Incandesces on contact with fluorine.3... 

Top row the three components of the Yandulov-Schrock cycle for catalytic dinitrogen reduction. Left the catalyst with the substrate Nj coordinated to Mo (Ar refers to the aryl substituent drawn in detail for one of the nitrogens). Centre the reductant bis(pentamethylcyclopentadienyl)chromium, CpjCr. Right the proton source 2,6-lutidinium borate. Bottom row vanadium complexes with intermediates of nitrogen reduction activated dinitrogen or diazenido(2—) (46a), imide (46b) and ammonia (46c). 

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