Metal-promoted reactions of 2-cyanopyridine: iron(II), cobalt(II), nickel(II), and copper(II) complexes of O-methylpyridine-2-carboximidate

Barnard, Paul F. B.

doi:10.1039/j19690002140

Cited by 54 publications

(8 citation statements)

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“…Thus the Cu(I)CO moiety appears to promote rapid and quantitative alcoholysis of one of the nitrile functions. There is some precedence for such a reaction in both alkyne [5] and nitrile [6] chemistry, and based on these observations as well as our own, we suggest a mechanism in which precoordination of nitrile occurs, followed by polarization and nucleophilic attack by the alcohol. Rate enhancement is typically large in cases of metal assisted solvolysis [7].…”

Section: Resultssupporting

confidence: 66%

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Dicyanoimidazole complexes of Cu(I): a carbonyl assisted alcoholysis of nitrile

Rasmussen

Rong-guang

Butler

et al. 1986

Inorganica Chimica Acta

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We describe a series of compounds which result from the reaction of Cu(1) with 4,5dicyanoimidazole. This ligand is far more acidic than imidazole and in all cases forms complexes as the anion. The presence of carbon monoxide with Cu(I) assists in the rapid alcoholysis of one of the nitrile groups. The resulting imino-ester remains coordinated to the copper in the phosphine derivative as confirmed by X-ray crystallography. The composition CUC~~H~~-N4Pz crystallizes in the space group Pbca with a = 14.140(4), b = 21.466(7), c = 24.577(8) a and Z = 8 molecules per cell. The copper is four coordinate and the bidentate imino-ester imidazole is nearly planar.

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Section: Resultssupporting

confidence: 66%

“…119.8(2) 108.5(4) 120.0(4) 105.5 (4) 114.1(4) 82.1(6) 111.4 7121.8 (6) 103.8(g) 111.3 (6) 103.0(9) 103.6(9) 113.5 (6) 113.6(7) 104(l) 118.1 7101.1 (9) 104.7 (9)…”

Section: Resultsmentioning

confidence: 99%

Dicyanoimidazole complexes of Cu(I): a carbonyl assisted alcoholysis of nitrile

Rasmussen

Rong-guang

Butler

et al. 1986

Inorganica Chimica Acta

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“…The intensity of the N2-H stretching bands varies from medium (in 2 and 3) to weak (in 1, 4). The C6=N2 and C5=C3 stretching modes are presented as two sharp intense bands, which are consistent with the previously reported values of the bands [26,45,46].…”

Section: Ir Analysissupporting

confidence: 92%

Activation of the Cyano Group at Imidazole via Copper Stimulated Alcoholysis

et al. 2019

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Reactions of 4,5-dicyano-1-methylimidazole with CuX2 (X = Cl, Br) in alcohol solvents (ethanol and methanol) resulted in the formation of Cu(II) carboximidate complexes [CuCl2(5- cyano-4-C(OEt)N-1-methylimidazole)(EtOH)] (1), [Cu2(µ-Cl)2Cl2(5-cyano-4-C(OMe)N-1-methylimidazole)2] (2), [Cu2(µ-Br)2Br2(5-cyano-4-C(OMe)N-1-methylimidazole)2] (3), and [Cu2(µ-Br)2Br2(5-cyano-4-C(OEt)N-1-methylimidazole)2] (4). The structures were determined by the X-ray crystallographic method, and further spectroscopic and computational methods were employed to explain the structural features. The solvent contributed to the alcoholysis reaction of the cyano group, as the result of which the ligand coordinated to the metal center in bidentate mode forming a five-membered chelating ring. In 1, the solvent also acts as an additional ligand, which coordinates to the metal center of a monomeric complex. In compounds 2–4, two halogen ligands link the metal atoms forming dihalo-bridged copper dimers. The infrared absorption characteristics were verified by simulation of the infrared spectra at the density functional theory level. In addition, the electronic absorption characteristics were explained by simulation of the UV–Vis spectra using the TD-DFT method. Molecular modelling at the DFT level was performed to study the effects of halogen type and steric hindrance of the alkoxy groups in forming the copper(II) complexes.

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“…1673 cm À1 in all the complexes is presumably due to a change in the C@N bond order on coordination through the nitrogen atom, facilitated by transfer of electron density from CAOAC 2 H 4 AOAC moiety. The electron density on the ACAOAC 2 H 4 AOAC fragment of the 1-amidino-O-2-alkoxyethylurea group is more delocalized in the complexes and the bond order C@O group is raised [31,32]. The IR spectra of the complexes show strong absorption band at ca.…”

Section: Ir Spectral Studiesmentioning

confidence: 96%