Synthesis and properties of complexes Fe(Co)2(CNR)(1, 4-diaza-1, 3-butadiene) obtained by heterogeneously (Pd/C) catalyzed substitution of a CO by an isocyanide ligand. Crystal structure of Fe(Co)2(t-BuNC)(N, N′-p-tolyl- 1, 4-diaza- 1,3-butadiene)

Kraakman, M. J. A.; Wijnkoop, Maarten van; Frühauf, Hans‐Werner; Vrieze, K.; Smeets, Wilberth J. J.; Spek, Anthony L.

doi:10.1016/s0020-1693(00)86118-6

Cited by 14 publications

(25 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[40,41,43,44] The geometries of several five-coordinated [Fe(1,4-dihetero-1,3-butadiene)] complexes, determined by X-ray structures, change from approximately tbp to sqp with increasing π-acceptor properties of the 1,4-dihetero-1,3-butadiene ligand. [44][45][46][47] The observed sqp geometry in 6g, in which the α-imino ketone exhibits good π-acceptor properties, is in agreement with this observation.…”

Section: Molecular Structure Of σ-Nσ-o-fe(co) 3 [Men‫؍‬ C(ph)c(ph)‫؍supporting

confidence: 83%

“…This effect is also observed in the 13 C-NMR spectra of complexes 8 and might explain the chemoselectivity for C-C coupling at the ketone carbon atom leading to complexes 3 and 8. Comparable changes in bond lengths, although less pronounced, have been found in [Fe(CO) 2 (tBuNC)(pTol-DAB)] [47] and [Fe(CO) 3 (2,6-iPr 2 C 6 H 3 -DAB)]. [40] The Fe-C ( The Fe(1)-Fe(2) bond length in 8a is 2.372(2) Å , i.e.…”

Section: Molecular Structure Of σ-Nσ-o-fe(co) 3 [Men‫؍‬ C(ph)c(ph)‫؍mentioning

confidence: 91%

See 1 more Smart Citation

Preparation and Properties of Carbonyliron Complexes of 1-Aza-4-oxa-1,3-butadiene (α-Imino Ketone) – X-ray Crystal Structures of Fe(CO)3[MeNC(Ph)C(Ph)=O] and Fe2(CO)4[tBuNC(H)(Me)C(O)(O)C(Me)C(H)=NtBu]

Siebenlist¹,

Frühauf²,

Vrieze³

et al. 2000

Eur. J. Inorg. Chem.

Self Cite

View full text Add to dashboard Cite

The reaction of Fe2(CO)9 at room temperature in THF or toluene with the α‐imino ketones R1N=C(R2)–C(R3)=O (L) (R1 = alkyl, R2 = H, Me, Ph, R3 = Me, Ph) (a–k), initially results in the formation of the mononuclear chelate Fe(CO)3(α‐imino ketone) complexes 6 which can be isolated in moderate (6h) to high (6e–g) yield. Under these reaction conditions, complexes 6 subsequently react with [Fe(CO)4] fragments or dimerise, to form the dinuclear complexes Fe2(CO)6(α‐imino ketone) (7a–j) or Fe2(CO)4(L–L) (8a,b,k), respectively. The complexes 8 contain two α‐imino ketone ligands C–C coupled at the ketone carbon atoms. Complexes 8a,b react with CO at elevated temperatures to quantitatively yield Fe(CO)3(α‐imino ketone) (6a,b). This reaction can be reversed photochemically. Irradiation of a solution of 6a,b in the low‐energy band results in the reformation of 8a,b in almost quantitative yield. The extremely air‐sensitive complexes 6 and the dinuclear complexes 7 and 8 have been characterised spectroscopically (IR, UV/Vis, 1H and 13C NMR) and by elemental analysis. The solid state structures of complexes 6g and 8a have been determined by single‐crystal X‐ray diffraction. The molecular structure of 6g confirms the flat σ‐O,σ‐N chelate coordination of the α‐imino ketone. The structure of 8a consists of two metal–metal‐bonded Fe(CO)2 units, bridged by a formally 10e‐donating dianionic C–C coupled (tBu‐ADO) ligand. A mechanism for the formation of complexes 8 is discussed.

show abstract

Section: Molecular Structure Of σ-Nσ-o-fe(co) 3 [Men‫؍‬ C(ph)c(ph)‫؍supporting

confidence: 83%

Section: Molecular Structure Of σ-Nσ-o-fe(co) 3 [Men‫؍‬ C(ph)c(ph)‫؍mentioning

confidence: 91%

Preparation and Properties of Carbonyliron Complexes of 1-Aza-4-oxa-1,3-butadiene (α-Imino Ketone) – X-ray Crystal Structures of Fe(CO)3[MeNC(Ph)C(Ph)=O] and Fe2(CO)4[tBuNC(H)(Me)C(O)(O)C(Me)C(H)=NtBu]

Siebenlist¹,

Frühauf²,

Vrieze³

et al. 2000

Eur. J. Inorg. Chem.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The central C C bond is accordingly shortened because the p*-orbital is bonding between these two carbons. This shortening of the central C-C bond is also found in the solid state structures of Fe(CO) 3 (R-DAB) [31,32] complexes and Fe(CO) 3 (MeN C(Ph) C(Ph) O) [33].…”

Section: Synthesis Of Fe(co) 3 (Et 4 -Dto) (7d)supporting

confidence: 68%

“…A similar pattern is observed for the (alkyl-DAB)M(CO) 3 (M= Fe, Ru) [31,[76][77][78] complexes. The position of the CO stretching bands of 7a,d compare well with those of Fe(CO) 3 (p-Tol, p-An-DAB) [32], suggesting that the DTO ligands also possess a similar low-lying p*-LUMO level. The higher CO stretching frequencies of 7d compared to 7a indicate that the Et 4 -DTO is a better p-acceptor than cyclo-DTO.…”

Section: Complexesmentioning

confidence: 66%

“…As a result of the extensive p-back donation, the thiocarbonyl carbon atom resonances are shifted 22.7 and 19.4 ppm to lower frequency in comparison with those of the free ligands. Comparable shifts to lower frequency have been observed for the ketone carbon atom in Fe(CO) 3 (a-iminoketone) [33], whereas somewhat smaller shifts have been found for the imine carbon atoms in Fe(CO) 3 (R-DAB) [32] and Fe(CO) 3 (a-iminoketone). The three terminal CO ligands in complexes 7a,d give rise to a single resonance at 213.6 and 210.8 ppm indicating that they rapidly interchange on the NMR time scale at 263 K. This interchange has also been observed for the M(CO) 3 (R-DAB) (M = Fe, Ru) [76,82,83] and Fe(CO) 3 (a-iminoketone) and may be explained by Berry pseudo-rotations [84].…”

Section: Complexesmentioning

confidence: 85%

See 1 more Smart Citation

1,3-Dipolar cycloaddition to the FeSC fragment 20. Preparation and properties of carbonyliron complexes of di-thiooxamide. Reactivity of the mononuclear (di-thiooxamide)Fe(CO)3 towards dimethyl acetylenedicarboxylate

Siebenlist

Frühauf

Kooijman

et al. 2002

Inorganica Chimica Acta

Self Cite

View full text Add to dashboard Cite

A Theoretical Study on the Complete Catalytic Cycle of the Hetero‐Pauson–Khand‐Type [2+2+1] Cycloaddition Reaction of Ketimines, Carbon Monoxide and Ethylene Catalyzed by Iron Carbonyl Complexes

Imhof

Anders

Göbel

et al. 2003

Chemistry A European J

View full text Add to dashboard Cite

The [2+2+1] cycloaddition reaction of 1,4-diazabutadienes, carbon monoxide and ethylene catalyzed by iron carbonyl complexes produces pyrrolidin-2-one derivatives. Only one of the two imine moieties is activated during the catalysis. The mechanism of this cycloaddition reaction is studied by density functional theory at the B3LYP/6-311++G(d,p) level of theory. In accordance with experimental results, a [(diazabutadiene)Fe(CO)(3)] complex of square-pyramidal geometry is used as the starting compound S of the catalytic cycle. Based on experimental experience, the reaction with ethylene is considered to take place before any interaction with carbon monoxide. According to the computational results, the reaction does not proceed by ligand dissociation followed by addition of ethylene and subsequent intramolecular activation steps but by the approach of an ethylene molecule from the base of the square-pyramidal complex. This reaction yields an intermediate I(4) in which ethylene is coordinated to the iron centre and a new C-C bond between ethylene and one of the imine groups is formed. The insertion of a terminal carbon monoxide ligand into the metal-carbon bond between ethylene and iron produces the key intermediate I(7). The reaction proceeds by metal-assisted formation of a lactam P. The catalytic cycle is closed by a ligand-exchange reaction in which the diazabutadiene ligand substitutes P with reformation of S. This reaction pathway is found to be energetically favored over a reductive elimination. It leads to the experimentally observed heterocyclic product P and a reactive [Fe(CO)(3)] fragment.

show abstract

Synthesis and properties of complexes Fe(Co)2(CNR)(1, 4-diaza-1, 3-butadiene) obtained by heterogeneously (Pd/C) catalyzed substitution of a CO by an isocyanide ligand. Crystal structure of Fe(Co)2(t-BuNC)(N, N′-p-tolyl- 1, 4-diaza- 1,3-butadiene)

Cited by 14 publications

References 71 publications

Preparation and Properties of Carbonyliron Complexes of 1-Aza-4-oxa-1,3-butadiene (α-Imino Ketone) – X-ray Crystal Structures of Fe(CO)3[MeNC(Ph)C(Ph)=O] and Fe2(CO)4[tBuNC(H)(Me)C(O)(O)C(Me)C(H)=NtBu]

Preparation and Properties of Carbonyliron Complexes of 1-Aza-4-oxa-1,3-butadiene (α-Imino Ketone) – X-ray Crystal Structures of Fe(CO)3[MeNC(Ph)C(Ph)=O] and Fe2(CO)4[tBuNC(H)(Me)C(O)(O)C(Me)C(H)=NtBu]

1,3-Dipolar cycloaddition to the FeSC fragment 20. Preparation and properties of carbonyliron complexes of di-thiooxamide. Reactivity of the mononuclear (di-thiooxamide)Fe(CO)3 towards dimethyl acetylenedicarboxylate

A Theoretical Study on the Complete Catalytic Cycle of the Hetero‐Pauson–Khand‐Type [2+2+1] Cycloaddition Reaction of Ketimines, Carbon Monoxide and Ethylene Catalyzed by Iron Carbonyl Complexes

Contact Info

Product

Resources

About