Synthesis of Bis(trityl)iron(II) and Formation of the Iron(0)-Stabilized o,o-Isomer of Gomberg’s Dimer

Abstract

by the Klaüi ligand. In summary, we have synthesized bis(trityl)iron(II), [Fe(η 5 -CPh 3 ) 2 ] (1). Complex 1 has proven to be a good source of Fe(0), as evidenced by its reactions with CO and P(OMe) 3 , which result in the formation of [Fe(CO) 5 ] and [(μ,η 4 :η 4 -Ph 2 CC 6 H 5 C 6 H 5 CPh 2 ){Fe(P(OMe) 3 ) 3 } 2 ], respectively. The latter complex represents the first observation of the o,oisomer of Gomberg's dimer, which differs from the usual α,pisomer found in solution and the solid-state, and provides a further understanding of this historically important system. Additionally, given our preliminary results, we suggest that 1 could function as a precursor to low-valent Fe APNCs, a class of materials that has resisted isolation thus far. 12,51,52The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.organomet.1c00616.Experimental, spectroscopic, and crystallographic details for complexes 1−3 (PDF)Accession Codes CCDC 2116037−2116039 contain the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk

Photolytic or Oxidative Fragmentation of Trityl Diazeniumdiolate (O2N2CPh3–): Evidence for Both C–N and N–N Bond Cleavage

“…This substituent can exist in anionic and cationic forms , and also as a neutral radical, which is in equilibrium with Gomberg’s dimer. − We have previously used the favorable redox properties of this group to generate metal–ligand multiple bonds − and polychalcogenide complexes via C–E (E = O, S) bond cleavage. Additionally, the trityl complexes [M II (CPh 3 ) 2 ] (M = Fe, Ni) have proven to be good M 0 synthons due to the facile formation of • CPh 3 . , Accordingly, we reasoned that the C–N bond of a trityl C -DAZD would be especially susceptible to cleavage, enhancing its ability to release NO. Herein, we report the synthesis and characterization of the first C -DAZD complex supported by a trityl group, as well as its response to photolysis and oxidation.…”

Iron(I) Complex Bearing an Open-Shell Diazenido Ligand

“…The (cyclohexadienyl)­iron­(II) diazenido complex 7 was characterized by NMR, 57 Fe Mössbauer spectroscopy, and single-crystal X-ray diffraction study (Figure c). Its Fe–N­(diazenido) distance (1.669(2) Å) is close to those of its congeners in 2 and apparently shorter than that in 1 , and the 57 Fe Mössbauer isomer shift (δ = 0.35 mm/s) is comparable to that of the low-spin bis­(cyclohexadienyl)­iron­(II) complex [Fe­(η 5 -C 6 H 5 CPh) 2 ] (δ = 0.38 mm/s) . These characterization data point out that the reaction producing 7 involves ligand-replacement and electron-transfer processes between 1 and the trityl radical.…”