Preparation and Characterization of the Triflate Complex [Cp*(dppe)FeOSO₂CF₃]: A Convenient Access to Labile Five‐ and Six‐Coordinate Iron(I) and Iron(II) Complexes

Abstract

Treatment of the iron hydride [Cp*(dppe)FeH] (1) with methyl triflate (CH 3 OSO 2 CF 3 ) yielded the iron triflate adduct [Cp*(dppe)FeOSO 2 CF 3 ] (4, 85 %). In the solid state, the triflate is coordinated at the iron center as shown by XRD (d Fe-O = 2.118(4) Å) and IR spectroscopy (ν SO = 1305 cm -1 ). In solution, 4 is in equilibrium with the 16-electron species [Cp*(dppe)Fe]-OSO 2 CF 3 (5(OSO 2 CF 3 )), 4/5(OSO 2 CF 3 ) = 2:1). The CV of 4 displays two waves (E 1 = -0.74 V, E 2 = 0.24 V vs. SCE) assigned to [a]

Rip It off: Nitro to Nitroso Reduction by Iron Half-Sandwich Complexes

“…increases the amount of s-electron density at the metal indirectly, resulting in I.S. values similar to those recently reported for the Fe II hydride complex [FeH(dppe)Cp*]27,31 , and significantly lower than the Fe III compounds [4] + and [6] + . Indeed, comparison of Fe II and Fe III chlorides1 and [4]…”

“…With the terminal alkyne and nitrile functional groups in [7a] and [7b] + effectively masked by coordination to the iron centre, these complexes were subsequently reacted with an excess of 1 and Na[BAr [3m] + is shifted to higher-field and found at 101.3 ppm (Table S4). The bimetallic compounds [8a/b] +/2+ exhibit two singlets in the 31 ). The 13 C{ 1 H} shift of the Cp moiety also proved sensitive to the electronic nature of the nitroso ligand substituent (Figure S16).…”

“…Rather, the formation of [4] + can be attributed to reaction of {Fe(dppe)Cp} + with dichloromethane. 31 The further byproduct [5] + (Scheme 2, Figure 2) was obtained as a blue solid in various quantities (usually <10 %). Compound [5] + most probably originates by abstraction of an oxygen atom from the nitro substrate and subsequent internal rearrangement (see Scheme 4 below).…”

“…31 P{ 1 H} NMR spectra of[3] + and conventional chemical shifts of the resonances are strongly supportive of a diamagnetic Fe II oxidation state and a neutral nitroso ligand. Contrary, paramagnetic Fe III species [4-6] + exhibit broadened1 H NMR resonances, and the 31 P{1 H} NMR resonances are essentially indistinguishable from the background noise level (ESI) 27.…”

Reductive Electropolymerization and Electrochromism of Iron(II) Complex with Styrene-Based Ligand

“…In case of complex 1 the two quasi-reversible oxidation/reduction waves have been observed with the half-wave potentials of −0.29 V and +0.76 V (Figure 3). [32][33][34]. One additional irreversible wave assigned to the oxidation of the ligand molecule has been observed at +1.07 V in the anodic scan.…”