The second isomer of dichloro(2,2'-bipyridine)iron(II): syntheses and spectroscopic and magnetic characterizations of three related dichloro(.alpha.-diimine)iron(II) complexes containing five-coordinate, high-spin iron(II)

Charron, Francis F.; Reiff, W. M.

doi:10.1021/ic00236a026

Cited by 26 publications

(8 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the employment of the NHC ligand generated in situ as a reductant to bring Fe III back to Fe II significantly limited the yield. In our approach, the heteroleptic Fe II structure could be achieved by directly ligating the Fe II center with first bpy and then the btz ligand generated in situ, by the isolation of Fe(bpy)Cl 2 20. 25 This is also different from the not‐executed opposite approach, namely assembling the NHC first and the other ancillary ligand later, which would either have involved the air‐sensitive intermediate FeCl 2 (PPh 3 ) 2 26 or be limited by the electron stoichiometry (two electrons per Fe for two NHC sites) based on an electrochemical method 27.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

A Heteroleptic Ferrous Complex with Mesoionic Bis(1,2,3‐triazol‐5‐ylidene) Ligands: Taming the MLCT Excited State of Iron(II)

Liu

Kjær

Fredin

et al. 2014

Chemistry A European J

148

218

View full text Add to dashboard Cite

Strongly σ-donating N-heterocyclic carbenes (NHCs) have revived research interest in the catalytic chemistry of iron, and are now also starting to bring the photochemistry and photophysics of this abundant element into a new era. In this work, a heteroleptic Fe(II) complex (1) was synthesized based on sequentially furnishing the Fe(II) center with the benchmark 2,2'-bipyridine (bpy) ligand and the more strongly σ-donating mesoionic ligand, 4,4'-bis(1,2,3-triazol-5-ylidene) (btz). Complex 1 was comprehensively characterized by electrochemistry, static and ultrafast spectroscopy, and quantum chemical calculations and compared to [Fe(bpy)3](PF6)2 and (TBA)2[Fe(bpy)(CN)4]. Heteroleptic complex 1 extends the absorption spectrum towards longer wavelengths compared to a previously synthesized homoleptic Fe(II) NHC complex. The combination of the mesoionic nature of btz and the heteroleptic structure effectively destabilizes the metal-centered (MC) states relative to the triplet metal-to-ligand charge transfer ((3)MLCT) state in 1, rendering it a lifetime of 13 ps, the longest to date of a photochemically stable Fe(II) complex. Deactivation of the (3)MLCT state is proposed to proceed via the (3)MC state that strongly couples with the singlet ground state.

show abstract

Section: Resultsmentioning

confidence: 99%

“… Synthetic pathways for complex 1 . a) Ethanol, 10 equiv FeCl 2 , 60 °C,20 82 % based on bpy; b) K 2 CO 3 , CuSO 4 , Na ascorbate, pyridine, t BuOH/H 2 O, RT,21 70 %; c) 1) MeOTf, ClCH 2 CH 2 Cl, −78 °C to RT to 100 °C,12d 2) NH 4 PF 6 (aq. ), 85 %; d) t BuOK, THF, −78 °C to RT, 45 %.…”

Section: Resultsmentioning

confidence: 99%

A Heteroleptic Ferrous Complex with Mesoionic Bis(1,2,3‐triazol‐5‐ylidene) Ligands: Taming the MLCT Excited State of Iron(II)

Liu

Kjær

Fredin

et al. 2014

Chemistry A European J

148

218

View full text Add to dashboard Cite

show abstract

“…The difference between these works may originate either from the formation of iron chlorides through the use of Et 4 NCl or from the methods of preparation of [(bpy)FeCl 2 ]. [33][34][35][36] It should also be noted that metal-centered Fe(III/II), Fe(II/I) and Fe(I/0) reductions were described previously for (bpy)Fe complexes. 33,[37][38][39][40][41][42][43] In the present work, we have traced the reduction processes at every stage by ESR spectroscopy and observed a transition from the paramagnetic particles corresponding to the Fe(III) state (before the reduction) to diamagnetic Fe(II) (E 1 ).…”

Section: Cyclic Voltammetrymentioning

confidence: 64%

“…33-36 5 It should also be noted that metal-centered Fe (III/II), Fe (II/I) and Fe (I/0) reductions were described previously for (bpy)Fe complexes. 33,[37][38][39][40][41][42][43] In the present work, we have traced the reduction processes at every stage by ESR spectroscopy and observed a transition from the paramagnetic particles 10 corresponding to Fe (III) state (before the reduction) to diamagnetic Fe (II) (E 1 ). The free bpy radical-anion signal appears only at the potentials of E 4 (Table 2), providing a g value of 2.0030.…”

Section: Cyclic Voltammetrymentioning

confidence: 99%

Iron-catalyzed electrochemical C–H perfluoroalkylation of arenes

et al. 2015

View full text Add to dashboard Cite

A new iron-catalyzed reaction for the coupling of perfluoroalkyl iodides (RFI) with aromatic substrates is described. The perfluoroalkylated arene products are obtained in good to excellent yields in the presence of a [(bpy)Fe(ii)] catalyst (10%) electrochemically regenerated or generated from [(bpy)Fe(iii)] at room temperature. The development, scope, and preliminary mechanistic studies of these transformations are reported.

show abstract

“…Both the red ,13a and the orange 13b isomers of FeCl 2 (bpy) were prepared following the method previously reported. Also the FeCl 2 (phen) was obtained using the same method. , The tris(2,2‘-bipyridine) [Fe(bpy) 3 ]Cl 2 ·5H 2 O complex was prepared by a procedure previously described . The spectroscopic data (IR and NMR) of the new complexes are reported in Tables and .…”

Section: Methodsmentioning

confidence: 99%

Preparation and Reactivity of Mixed-Ligand Iron(II) Hydride Complexes with Phosphites and Polypyridyls

et al. 2004

View full text Add to dashboard Cite

Hydride complexes [FeH(N-N)P3]BPh4 (1, 2) [N-N = 2,2'-bipyridine (bpy) and 1,10-phenanthroline (phen); P = P(OEt)4, PPh(OEt)2, and PPh2OEt] were prepared by allowing FeCl2(N-N) to react with phosphite in the presence of NaBH4. The hydrides [FeH(bpy)2P]BPh4 (3) [P = P(OEt)3 and PPh(OEt)2] were prepared by reacting the tris(2,2'-bipyridine) [Fe(bpy)3]Cl2.5H2O complex with the appropriate phosphite in the presence of NaBH4. The protonation reaction of 1 and 2 with acid was studied and led to thermally unstable (above -20 degrees C) dihydrogen [Fe(eta2-H2)(N-N)P3]2+ (4, 5) derivatives. The presence of the H2 ligand is indicated by short T(1 min) values (3.1-3.6 ms) and by J(HD) measurements (31.2-32.5 Hz) of the partially deuterated derivatives. Carbonyl [Fe(CO)(bpy)[P(OEt)3]3](BPh4)2 (6) and nitrile [Fe(CH3CN)(N-N)P3](BPh4)2 (7, 8) [N-N = bpy, phen; P = P(OEt)3 and PPh(OEt)2] complexes were prepared by substituting the H2 ligand in the eta2-H2 4, 5 derivatives. Aryldiazene complexes [Fe(ArN=NH)(N-N)P3](BPh4)2 (9, 10, 11) (Ar = C6H5, 4-CH3C6H4) were also obtained by allowing hydride [FeH(N-N)P3]BPh4 derivatives to react with aryldiazonium cations in CH2Cl2 at low temperature.

show abstract

The second isomer of dichloro(2,2'-bipyridine)iron(II): syntheses and spectroscopic and magnetic characterizations of three related dichloro(.alpha.-diimine)iron(II) complexes containing five-coordinate, high-spin iron(II)

Cited by 26 publications

References 2 publications

A Heteroleptic Ferrous Complex with Mesoionic Bis(1,2,3‐triazol‐5‐ylidene) Ligands: Taming the MLCT Excited State of Iron(II)

A Heteroleptic Ferrous Complex with Mesoionic Bis(1,2,3‐triazol‐5‐ylidene) Ligands: Taming the MLCT Excited State of Iron(II)

Iron-catalyzed electrochemical C–H perfluoroalkylation of arenes

Preparation and Reactivity of Mixed-Ligand Iron(II) Hydride Complexes with Phosphites and Polypyridyls

Contact Info

Product

Resources

About