Group VI Metal Carbonyls Research Articles

The preparation of some group VI fluorometal carbonyl derivatives

It has been found that fluoride ion can behave as a ligand towards the Group VI metal carbonyls. Thus the anions Cr(CO) 5F − and W(CO) 5F − were isolated and characterized. These products could be prepared by reaction of [(C 6H 5) 3P] 2NF with the hexacarbonyls or by reaction of AgF with the dianions M 2(CO) 10 2− (M = Cr or W). Their infrared spectra are discussed.

Ditertiary alkylphosphine derivatives of the Group VI metal carbonyls and their oxidation with iodine

The preparation and characterisation of the complexes fac,fac-[M2(CO)6(dmpe)3](M = Cr, Mo, W; dmpe is Me2PCH2CH2PMe2) and cis-[M (CO)2(dmpe)2] is reported. The oxidation of cis-[M(CO)4(dmpe)] with iodine gives [M(CO)4(dmpe)I]I which can be converted into [M(CO)3(dmpe)I2](M = Mo, W). Iodine oxidation of fac,fac-[M2(CO)6(dmpe)3] gives [M2(CO)4(dmpe)3I4](M = MO, W), which are also obtained from the reaction of [M (CO)3(dmpe)I2] with dmpe. Oxidation of cis-[M(CO)2(dmpe)2] gives [M(CO)2(dmpe)2I]I (M = Mo, W) which are also obtained in the reaction of [M2(CO)4(dmpe)3I4] with dmpe. The products of these oxidation reactions have been characterised by i.r. and n.m.r. (1H and 31P) spectroscopy. The cations [M(CO)2(dmpe)2I]+ are shown to be fluxional in the temperature range 220–320 K and a monocapped trigonal prismatic structure is indicated for the low-temperature form. Comparisons are made with analogous complexes containing Ph2PCH2CH2PPh2(dpe) and differences in their behaviour on oxidation are explained in terms of the steric effect of the substituents (methyl, phenyl) at phosphorus.

Group VI metal carbonyl catalyzed reaction of ethers and acid halides

Group VI metal carbonyl catalyzed reaction of ethers and acid halides

Electrochemical oxidation of organometallic complexes. Carbene and Lewis base complexes of chromium, molybdenum, and tungsten carbonyls

Tha oxidative one-electron transfer reactions of a wide variety of Group VI metal carbonyl derivatives have been detected by voltammetry. The compounds studied are of the type M(CO)6 –nLn or M(CO)6 – 2n(LL)n(M = Cr, Mo, W; L = monodentate Lewis base, n= 1 or 2; LL = bidentate Lewis base, n= 1 or 2) and carbene complexes of the type M(CO)5C(X)Y. The value of the potential, E½, is influenced by each of the variables M, L(or LL), n, X, and Y. The order of E½-values follows closely the apparent π-acceptor/σ-donor ratio of the ligand, but comparison with the results of molecular orbital calculations suggests that the influence of L (or of {C(X)Y}) upon the redox orbital is indirect. Steric effects are shown to influence the value of E½, especially where bidentate ligands are present. The oxidation potentials are related to synthetic chemistry in these systems.

Tertiary phosphine and arsine chalcogenide derivatives of Group VI metal carbonyl complexes

The preparation of a series of complexes [M(CO)5L][M = Cr or W; L = Me3PS, Me2PhPS, MePh2PS, Ph3PS, Me2PhPSe, Me3AsS, or Ph2P(S)CH2P(S)Ph2; M = Mo, L = Me2PhPS; M = W, L = Ph3AsO] is reported. I.r. and 1H n.m.r. spectra are discussed. The chalcogenide ligands are readily displaced by CO and Ph3P, and with Mel ionic species, e.g.[Me2PhPSMe][M(CO)5l], are formed. For L = Ph2P(S)CH2P(S)Ph2 spectroscopic evidence indicates the ligand is acting in a monodentate fashion.

Kinetics of the reaction of acetonitrile on group VI metal carbonyls

A kinetic investigation of the reaction of acetonitrile on Group VI hexacarbonyls has shown the process to be stepwise, and that substitution by acetonitrile leads to increased replacement rates. A two-term rate law of the form Rate = k 1[ M(CO) 6] + k 2[ M(CO) 6][CH 3CN] is obeyed. Acetonitrile is seen to be as effective a nucleophile as triphenylphosphine towards Mo(CO) 6.

Photochemical substitution reactions of substituted Group VI metal carbonyls

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhotochemical substitution reactions of substituted Group VI metal carbonylsG. Schwenzer, M. Y. Darensbourg, and D. J. DarensbourgCite this: Inorg. Chem. 1972, 11, 8, 1967–1970Publication Date (Print):August 1, 1972Publication History Published online1 May 2002Published inissue 1 August 1972https://doi.org/10.1021/ic50114a055RIGHTS & PERMISSIONSArticle Views184Altmetric-Citations32LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (548 KB) Get e-Alerts Get e-Alerts

σ-bonded complexes of substituted phospha- and arsacarboranes and their π-ollyl derivatives

The photochemical reaction of (1,7-B 9H 9CHE) 2Fe 2− (E  P or As) with Group VI metal carbonyls leads to the formation of complexes with the general formula, [1,7-B 9H 9CHE-M(CO) 5] 2Fe 2−. It is proposed that each heteroatom carborane ligand is π-bonded to the iron atom and σ-bonded through either the phosphorus or arsenic atom to a Group VI metal carbonyl. The preparation and characterization of a neutral phosphacarborane σ-complex is described.

Reactions of group VI metal carbonyls with some terdentate nitrogen donor ligands and the oxidation of the products with iodine

The hexacarbonyls of chromium, molybdenum and tungsten react with three terdentate nitrogen donor ligands, T, to give fac-M(CO) 3T derivatives, where T = bis-(2-pyridylmethyl)amine, bis(2-pyridylmethyl)methylamine and bis(2-pyridylethyl)-amine. Mo(CO) 3(cycloheptatriene) and W(CO) 3(acetonitrile) 3 have also been used to prepare two of these products. The action of iodine on the fac-Mo(CO) 3T and fac-W(CO) 3T derivatives has also been investigated. In all cases the products are seven-co-ordinate divalent metal compounds of the type [M(CO) 3(T)I] +I −. These iodo derivatives are the first of this type to contain terdentate nitrogen ligands.

The Synthesis and Reactions of some Dialkylaminodifluorophosphine Derivatives of the group VI Metal Carbonyls

Abstract Two convenient syntheses of monosubstituted dialkylarninodifluorophosphine metal pentacarbonyls (metal [dbnd] Cr, Mo and W) are described. Reaction of these materials with anhydrous HBr produced the corresponding bromodifluorophosphine derivatives, BrPF2M(CO)5.

Nature of the intermediate procreated in substitution reactions of Group VI metal carbonyls

Nature of the intermediate procreated in substitution reactions of Group VI metal carbonyls

Improved preparation of tertiary phosphine and related substitution products of group VI metal carbonyls

The substitution of carbon monoxide in the Group VI metal carbonyls by tertiary phosphines, arsines, stibines or certain tertiary amines in boiling ethanol is strongly catalysed by sodium borohydride. This catalysis has been used to prepare a wide range of known and new substituted carbonyls of chromium, molybdenum and tungsten.

Preparation of some anionic acetylene complexes of the Group VI metal carbonyls

The photochemical reactions of the Group VI metal hexacarbonyls with the acetylide ion, C≡CR– where the metal is Cr, Mo, or W, and R is Me or Ph are described. The bonding in these complexes is discussed and their reactions with triphenylphosphine are described.

Tertiary phosphine and arsine chalcogenide derivatives of the Group VI metal carbonyls

The addition of the title ligands to u.v.-irradiated tetrahydrofuran solutions of Cr(CO)6 or W(CO)6 have produced new derivatives of the type M(CO)5L; 1H n.m.r. studies in benzene show these compounds to be associated with the solvent molecule.

A New Synthetic Approach to Substituted Group VI Metal Carbonyl Anions; M(CO)5X[sbnd]

Abstract A simple, rapid synthesis of Group VI metal carbonyl anions of the type M(CO)5X[sbnd], (X = CN, SCN, l, Cl, and C [tbnd] CC6H5) has been found. Reaction of the dinuclear anions, M2(CO)10 [dbnd], with either silver salts, AgX, or mercuric salts, HgX2, affords the corresponding mononuclear anions in moderate to good yields

Substituted Group VI metal carbonyl complexes of dimethyl methylphosphonite and bis(dimethylamino)methylphosphine

Substituted Group VI metal carbonyl complexes of dimethyl methylphosphonite and bis(dimethylamino)methylphosphine

Transition metal chemistry VI. Calculation of force constants in the CO stretching region of cis-disubstituted group VI metal carbonyls and iron and carbonyl complexes with C2v symmetry

For complexes of the type cis-L 2M(CO) 4 (M = Mo, W, Cr; L = a phosphine, arsine or amine), (RHg) 2Fe(CO) 4 (R = Me, Bu) and (R 3M) 2Fe(CO) 4 (M = Pb, Sn, Si or Ge) all the CO stretching force constants are calculated using a rigorous algebraic procedure based on the Cotton and Kraihanzel force field.

Complexes of B 9H 10CHP − and B 9H 10CHAs − with group VI metal carbonyls

The photochemical reaction of (CH 3) 4N[B 9H 10CHE] (E = P or As) with group VI metal carbonyls lead to the formation of complexes of the general formula, (CH 3) 4N[B 9H 10CHE M(CO) 5]. Available evidence suggests that the phosphorus or arsenic atom of the ligand is σ-bonded to the metal carbonyl in these new derivatives.

Phosphorus-31 nuclear magnetic resonance study of tertiary phosphine derivatives of group VI metal carbonyls. III. Disubstituted compounds

Phosphorus-31 nuclear magnetic resonance study of tertiary phosphine derivatives of group VI metal carbonyls. III. Disubstituted compounds

Chemistry of the metal carbonyls. Part LVI. Reactions of bis(pentafluorophenyl)phosphine and tetrakis(pentafluorophenyl)diphosphine with Group VI metal hexacarbonyls

Reactions between bis(pentafluorophenyl)phosphine and Group VI metal carbonyls have been investigated and the mono-, di- and tri-substituted complexes [(C6F5)2PH]M(CO)5(M = Cr, Mo, W), [(C6F5)2PH]2M(CO)4(M = Cr, Mo), and [(C6F5)2PH]3Mo(CO)3 characterised. Treatment of the monosubstituted chromium and molybdenum complexes with n-butyl-lithium affords (C6F5)2P(Li)M(CO)5(M = Cr, Mo). Reaction of tetrakis(pentafluorophenyl)diphosphine with Cr(CO)6 and Mo(CO)6 gave polymeric complexes [(C6F5)4P2M(CO)4]n(M = Cr, Mo), and small yields of the monosubstituted complexes [(C6F5)2PH]Mo(CO)5. The anions [M(CO)5]2–(M = Cr, Mo) react with (C6F5)2PCl to give the monosubstituted diphosphine complexes (C6F5)4P2M(CO)5. The chromium complex was also prepared from (C6F5)2P(Li)Cr(CO)5 and (C6F5)2PCl.