Carbonyl halides of the Group VI transition metals. XXIV. 1,2-Bis(diphenylarsino)ethane complexes of the molybdenum(II) halocarbonyls

1971 ◽  
Vol 24 (11) ◽  
pp. 2223 ◽  
Author(s):  
MW Anker ◽  
R Colton
Keyword(s):  
Carbon Monoxide ◽  
Transition Metals ◽  
Pure Form ◽  
Species Comparison ◽  
Electronic Effects ◽  
Group Vi ◽  
Dicarbonyl Compounds ◽  
Relative Stabilities ◽  
Dimeric Complexes ◽  
Self Consistent

Complexes of the general formulae Mo(CO)3(dae)X2 and [Mo(CO)2(dae)1.5X2]2 [X = Cl, Br, I; dae = 1,2-bis(diphenylarsino)ethane] have been prepared and characterized. The chloro- and bromo-tricarbonyl species exist in two isomeric forms. All of the dae-bridged dimeric complexes can be cleaved by carbon monoxide, to reform the corresponding tricarbonyl, and by excess dae to give soluble dicarbonyl compounds which are thought to be of the type Mo(CO)2(dae)2X2. Unfortunately, the equilibria �������������� [Mo(CO)2(dae)1.5X2]2+dae ↔ 2Mo(CO)2(dae)2X2 are very labile, and all attempts to isolate the bis(dae) complexes in a pure form resulted in the precipitation of the sparingly soluble dimeric species. ��� Comparison of the complexes derived from the halocarbonyls with dae and other ditertiary phosphines and arsines shows that, as the halogen is varied, the changes in the relative stabilities of the complexes obtained within each ligand series are all explicable on the basis of a self-consistent steric argument, but comparison of the complexes of dae and its diphosphine analogue, dpe, suggests that electronic effects become significant on changing from arsenic to phosphorus donor atoms.

Carbony1 halides of the Group VI transition metals. XV. Complexes with Bis(1,2-diphenylphosphino)ethane

1969 ◽  
Vol 22 (7) ◽  
pp. 1341 ◽  
Author(s):  
MW Anker ◽  
R Colton ◽  
CJ Rix ◽  
IB Tomkins
Keyword(s):  
Carbon Monoxide ◽  
Transition Metals ◽  
Room Temperature ◽  
Conductivity Measurements ◽  
Group Vi ◽  
Complex Series ◽  
Reversible Reactions ◽  
New Type ◽  
Temperature And Pressure

Compounds of the general formulae M(CO)3(dpe)X2, [M(CO)2(dpe)1.5X2]2, and M(CO)2(dpe)2X2 have been prepared and characterized (M = Mo, W; dpe = bis- (1,2-diphenylphosphino)ethane; X = Cl, Br, I). All of the compounds are diamagnetic and most of them are non-electrolytes. However, conductivity measurements indicate that, for the iodo derivatives only, the bis(dpe) compounds should be formulated as 1 : 1 electrolytes, [M(CO)2(dpe)2I]I. ��� For the iodo series of compounds only, there is a complex series of reversible reactions including a new type of carbon monoxide carrying system. In addition, the dimeric dpe derivatives are cleaved by carbon monoxide at room temperature and pressure to give equal quantities of [M(CO)2(dpe)2I]I and M(CO)3(dpe)I2.

Carbonyl halides of the Group VI transition metals. IX. Complexes with Bis(diphenylarsino)methane: Some further carbon monoxide carriers

1968 ◽  
Vol 21 (5) ◽  
pp. 1159 ◽  
Author(s):  
MW Anker ◽  
R Colton ◽  
IB Tomkins
Keyword(s):  
Carbon Monoxide ◽  
Transition Metals ◽  
Room Temperature ◽  
Bidentate Ligand ◽  
The Other ◽  
Group Vi ◽  
Mixed Coordination ◽  
Temperature And Pressure

Complexes of the types MX2(CO)3(dam)2 and MX2(CO)2(dam)2 [M = Mo, W; X = Cl, Br; dam = bis(diphenylarsino)methane] have been prepared and characterized. The compounds are all non-electrolytes; in the tricarbonyls both of the potentially bidentate arsenic ligands are in fact acting only as monodentates, but in the dicarbonyls there is mixed coordination with one ligand monodentate and the other bidentate. The dicarbonyl complexes absorb carbon monoxide in solution at room temperature and pressure, a metal-arsenic bond of the bidentate ligand is broken, and the corresponding tricarbonyl compound is produced. The reaction is readily reversible; thus the system is an example of a carbon monoxide carrier.

Carbonyl halides of the Group VI transition metals. XVI. Reactions of Bis(diphenylphosphino)methane with Diiodotetracarbonyltungsten(II)

1969 ◽  
Vol 22 (12) ◽  
pp. 2535 ◽  
Author(s):  
R Colton ◽  
CJ Rix
Keyword(s):  
Carbon Monoxide ◽  
Transition Metals ◽  
Molecular Species ◽  
Direct Interaction ◽  
Ionic Species ◽  
Reaction Scheme ◽  
Simple System ◽  
Tricarbonyl Complex ◽  
Group Vi ◽  
Unusual Type

Compounds of the general formulae W(CO)3dpmI2 and W(CO)2(dpm)2I2 [dpm = bis(diphenylphosphino)methane] have been prepared by direct interaction of the ligand with diiodotetracarbonyltungsten(II). However, this apparently simple system is complicated by the existence of two isomers of the tricarbonyl complex and three isomeric forms of the dicarbonyl. The various isomers have been separated and characterized individually and the interconversions between all the complexes have been investigated. The overall reaction scheme contains a partial carbon monoxide carrying system and an example of an unusual type of isomerism: �������������������� W(CO)2(dpm)2I2 → [W(CO)2(dpm)2I]I that is, isomerism of a molecular species to an ionic species.

Carbonyl halides of the Group VI transition metals. V. Carbon monoxide carriers and some sulphur and nitrogen derivatives of molybdenum halocarbonyls

1968 ◽  
Vol 21 (1) ◽  
pp. 15 ◽  
Author(s):  
R Colton ◽  
GR Scollary ◽  
IB Tomkins
Keyword(s):  
Carbon Monoxide ◽  
Transition Metals ◽  
Direct Interaction ◽  
Group Vi ◽  
Derivatives Of

The blue compounds MX2(CO)2(Ph3P)2 (M = Mo and W, X = Cl and Br) have been shown to absorb carbon monoxide very readily indeed to form the corresponding tricarbonyls, and as reported earlier, the tricarbonyls may be easily converted into the dicarbonyls. The dicarbonyl is therefore a carbon monoxide carrier. The compounds Mo(CO)3 dtc2 and Mo(CO)2 dtc2 (dtc = diethyldithiocarbamate) also represent a carbon monoxide carrying system, but in this case both compounds are rather unstable. The compounds MoX2(CO)2 btp2 (btp = N-n-butylthiopicolinamide; X = Cl, Br) have been prepared by direct interaction of the ligand and the appropriate halocarbonyl. Although these compounds are believed to be monomeric they do not absorb carbon monoxide.

Carbonyl halides of the Group VI transition metals. XIX. Iodocarbonyl complexes of molybdenum and tungsten with Bis(diphenylarsino)methane

1970 ◽  
Vol 23 (3) ◽  
pp. 441 ◽  
Author(s):  
R Colton ◽  
CJ Rix
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Carbon Monoxide ◽  
Magnetic Resonance ◽  
Transition Metals ◽  
Direct Interaction ◽  
Acetone Solution ◽  
Group Vi ◽  
First Time ◽  
And Tungsten ◽  
Nuclear Magnetic

Complexes of the general formulae M(CO)3(dam)I2, M(CO)3(dam)2I2, and M(CO)2(dam)2I2 have been prepared and characterized [M = Mo, W; dam = bis(diphenylarsino)methane]. All of the compounds are diamagnetic and non-electrolytes in acetone solution. The tungsten derivatives were prepared by direct interaction of dam with diiodotetracarbonyltungsten(11), but the molybdenum analogues were obtained by iodine oxidation of the zero-valent complex Mo(CO)4(dam)2 whose preparation is reported for the first time in this paper. The bis(dam)tricarbonyl complexes, M(C0)3(dam)2I2, are unstable in solution giving M(CO)2(dam)I2 and free dam in equilibrium with undissociated complex. The bis(dam)tricarbonyl complexes also readily lose carbon monoxide, especially in the case of molybdenum, to give M(CO)z(dam)2I2. These dicarbonyl complexes readily absorb carbon monoxide to re-form the tricarbonyl complexes to give a reversible carbon monoxide carrying system. Overall, these systems may be represented by the general equations : M(CO)3(dam)I2 + dam ↔ M(CO)3(dam)2I2 + CO These equilibria have been studied using both infrared and nuclear magnetic resonance techniques.

Substituted carbonyl derivatives of the Group VI transition metals. IV. Reactions of some arene-metal tricarbonyls with Triaryl-phosphine and -arsine ligands

1973 ◽  
Vol 26 (3) ◽  
pp. 655 ◽  
Author(s):  
JA Bowden ◽  
R Colton ◽  
CJ Commons
Keyword(s):  
Carbon Monoxide ◽  
Solid State ◽  
Transition Metals ◽  
Steric Effects ◽  
Group Vi ◽  
Decomposition Products ◽  
Carbonyl Derivatives ◽  
Derivatives Of

The reactions of triphenylphosphine and triphenylarsine with (π- arene)M(CO)3 (M = Cr, Mo, W) to yield fac-M(CO)3(RPh3)3 (R = P, As) have been reexamined. Anomalies in the earlier literature have been resolved by the isolation of two solid state forms of each complex and by a study of the decomposition products of these compounds. Tricarbonyl complexes of tritolyl-phosphines and -arsines are also reported and their behaviour suggests steric effects initiate decomposition. In addition, a number of (π-arene)M(CO)3 compounds were shown to react with carbon monoxide to form M(CO)6.

Approximation of adsorption heats of carbon monoxide on transition metals by means of an empirical model

1983 ◽  
Vol 48 (10) ◽  
pp. 2735-2739
Author(s):  
Jiří Fusek ◽  
Oldřich Štrouf ◽  
Karel Kuchynka
Keyword(s):  
Carbon Monoxide ◽  
Heat Capacity ◽  
Transition Metals ◽  
Molar Heat Capacity ◽  
Metal Adsorption ◽  
Heat Of Fusion ◽  
Class Structure ◽  
Fundamental Parameters ◽  
Adsorption Heats ◽  
Pauling Electronegativity

The class structure of transition metals chemisorbing carbon monoxide was determined by expressing the following fundamental parameters in the form of functions: The molar heat capacity, the 1st and 2nd ionization energy, the heat of fusion, Pauling electronegativity, the electric conductivity, Debye temperature, the atomic volume of metal. Adsorption heats have been predicted for twelve transition metals.

Carbonyl halides of the Group VI transition metals. XI. Dithiocyanatocarbonyl derivatives of molybdenum and tungsten(II)

1968 ◽  
Vol 21 (6) ◽  
pp. 1435 ◽  
Author(s):  
R Colton ◽  
GR Scollary
Keyword(s):  
Transition Metal ◽  
Transition Metals ◽  
Ammonium Chloride ◽  
Pure State ◽  
Ammonium Thiocyanate ◽  
Donor Ligands ◽  
Group Vi ◽  
Derivatives Of ◽  
And Tungsten

Reaction of ammonium thiocyanate with dihalocarbonyls of molybdenum and tungsten(11) leads to the elimination of ammonium chloride and the formation of a dithiocyanatocarbonyl complex of the transition metal. Although the thiocyanatocarbonyls themselves have not been isolated in a pure state, a number of substituted derivatives with phosphorus donor ligands have been prepared and characterized. In general these complexes are less stable than the corresponding carbonyl halide derivatives.

Electronic effects in butadiene hydrogenation catalysed by the transition metals

2002 ◽  
Vol 229 (1-2) ◽  
pp. 251-259 ◽  
Author(s):  
R.B. Moyes ◽  
P.B. Wells ◽  
J. Grant ◽  
N.Y. Salman
Keyword(s):  
Transition Metals ◽  
Electronic Effects ◽  
Butadiene Hydrogenation
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