scholarly journals Synthesis and Characterization of Group-6 Metal Carbonyl Complexes of Aroyl Hydrazone Derivatives

2012 ◽  
Vol 9 (2) ◽  
pp. 807-817 ◽  
Author(s):  
Mohd Saleem ◽  
Mohita Sharma ◽  
Simpy Mahajan ◽  
H. N. Sheikh ◽  
B. L. Kalsotra
Keyword(s):  
Benzoic Acid ◽  
Metal Carbonyl ◽  
Carbonyl Oxygen ◽  
Azomethine Nitrogen ◽  
Carbonyl Complexes ◽  
H Nmr ◽  
Metal Carbonyl Complexes ◽  
Secular Equations ◽  
Ir Bands

Carbonyl complexes of Chromium, molybdenum and tungsten of composition, [M(CO)4L-L], (where M= Cr, Mo or W and L-L= benzoic acid[1-(Furan-2-yl)methylene]hydrazide (BFMH), benzoic acid[(thiophene-2-yl)methylene]hydrazide (BTMH), benzoic acid[1-(thiophene-2-yl)ethylidene] hydrazide (BTEH), benzoic acid (phenylmethylene)hydrazide (BPMH) and benzoic acid[1-(anisol-3-yl)methylene] hydrazide (BAMH) are reported. These have been prepared by refluxing metal carbonyls and the ligands in 1:1molar ratio. The complexes were characterized by elemental analysis, IR spectra, UV-vis spectra,1H NMR, TGA/DTA, conductivity and magnetic susceptibility measurements. The IR bands suggest that in all the complexes the ligands behave as neutral bidentate chelating type coordinating metal through carbonyl oxygen and azomethine nitrogen. The CO force constants and CO-CO interaction constants for these derivatives have been calculated using Cotton-Kraihanzel secular equations, which indicate poorπ-bonding ability of the coordinated ligands.

scholarly journals Synthesis and structures of ruthenium di- and tricarbonyl complexes derived from 4,5-diazafluoren-9-one

2015 ◽  
Vol 71 (11) ◽  
pp. 965-968 ◽  
Author(s):  
Jorge Jimenez ◽  
Indranil Chakraborty ◽  
Pradip Mascharak
Keyword(s):  
Metal Carbonyl ◽  
Carbonyl Complexes ◽  
Strong Absorption Band ◽  
Research Attention ◽  
Bidentate Coordination ◽  
Biological Targets ◽  
Beneficial Effects ◽  
H Nmr ◽  
Metal Carbonyl Complexes ◽  
Ruthenium Carbonyl

Carbon monoxide (CO) has recently been shown to impart beneficial effects in mammalian physiology and considerable research attention is now being directed toward metal–carbonyl complexes as a means of delivering CO to biological targets. Two ruthenium carbonyl complexes, namelytrans-dicarbonyldichlorido(4,5-diazafluoren-9-one-κ2N,N′)ruthenium(II), [RuCl2(C11H6N2O)(CO)2], (1), andfac-tricarbonyldichlorido(4,5-diazafluoren-9-one-κN)ruthenium(II), [RuCl2(C11H6N2O)(CO)3], (2), have been isolated and structurally characterized. In the case of complex (1), thetrans-directing effect of the CO ligands allows bidentate coordination of the 4,5-diazafluoren-9-one (dafo) ligand despite a larger bite distance between the N-donor atoms. In complex (2), thecisdisposition of two chloride ligands restricts the ability of the dafo molecule to bind ruthenium in a bidentate fashion. Both complexes exhibit well defined1H NMR spectra confirming the diamagnetic ground state of RuIIand display a strong absorption band around 300 nm in the UV.

scholarly journals Computational Characterization of Bidentate P-Donor Ligands: Direct Comparison to Tolman’s Electronic Parameters

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3176 ◽  
Author(s):  
Tímea Kégl ◽  
Noémi Pálinkás ◽  
László Kollár ◽  
Tamás Kégl
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Metal Carbonyl ◽  
Donor Ligands ◽  
Carbonyl Complexes ◽  
Electronic Effects ◽  
Functional Theory ◽  
Metal Carbonyl Complexes ◽  
Electronic Parameters

The applicability of two types of transition-metal carbonyl complexes as appropriate candidates for computationally derived Tolman’s ligand electronic parameters were examined with density functional theory (DFT) calculations employing the B97D3 functional. Both Pd(0)L2(CO) and HRh(I)L2(CO) complexes correlated well with the experimental Tolman Electronic Parameter scale. For direct comparison of the electronic effects of diphosphines with those of monophosphines, the palladium-containing system is recommended. The t r a n s influence of various phosphines did not show a major difference, but the decrease of the H-Rh-P angle from linear can cause a significant change.

scholarly journals Group 6 metal carbonyl complexes of cyclo-(P5Ph5)

2019 ◽  
Vol 91 (5) ◽  
pp. 785-796 ◽  
Author(s):  
Divine Mbom Yufanyi ◽  
Toni Grell ◽  
Menyhárt-Botond Sárosi ◽  
Peter Lönnecke ◽  
Evamarie Hey-Hawkins
Keyword(s):  
Theoretical Calculations ◽  
Metal Carbonyl ◽  
Carbonyl Complexes ◽  
Reaction Conditions ◽  
X Ray Crystallography ◽  
H Nmr ◽  
Metal Carbonyl Complexes ◽  
Group 6 ◽  
Phenyl Rings ◽  
Good Agreement

Abstract Group 6 metal (Cr, Mo, W) carbonyl complexes react with cyclo-(P5Ph5) to afford the phosphorus-rich complexes [Cr(CO)5{cyclo-(P5Ph5)-κP1}] (1), [{Cr(CO)5}2{μ-cyclo-(P5Ph5)-κP1,P3}] (2), [M(CO)4{cyclo-(P5Ph5)-κP1,P3}] (with M=Cr (3), Mo (4), W (exo-5, endo-5)) depending on the reaction conditions. Complexes 1–5 were characterised by 31P{1H} NMR and IR spectroscopy, elemental analysis, and X-ray crystallography. The cyclopentaphosphane remains intact and acts as monodentate (1), bridging (2) or bidentate (3–5) ligand. Compounds exo-5 and endo-5 are configurational isomers and essentially differ in the orientations adopted by the phenyl rings attached to the uncoordinated phosphorus atoms. The 31P{1H} NMR spectra show five multiplets for an ABCDE spin system. Theoretical calculations showed that exo-5 and endo-5 are practically isoenergetic, which is in good agreement with the observed equilibrium in solution between exo-5 and endo-5. The thermal properties of the complexes have also been evaluated.

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