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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The chemistry of group 6 and 7 transition metal organometallic nitrosyl complexes

Kolthamer, Brian William Stirling January 1979 (has links)
Nitrosyl chloride exhibits a number of different reaction modes in its reactions with monomeric and dimeric neutral carbonyl complexes of transition metals. From its reaction with [CpCr(CO)₃]₂ under controlled conditions, the organometallic compounds CpCr (CO)₂(NO) , CpCr(NO)₂Cl, [CpCrCl2]2, and [CpCr (NO) Cl₂]₂ can be obtained. In contrast.,, the analogous [CpM(CO)₃] ₂ (M — Mo or W) compounds react with C1N0 to produce CpM(CO)3Cl and CpM(NO)₂Cl in comparable yields. The (arene)M(CO)₃ (M = Mo or W) compounds form the polymeric [M(NO)2Cl2]n species via labile M (CO)₂(NO) 2Cl₂ intermediates under identical experimental conditions. Possible pathways leading to the formation of all products are presented. Trithiazyl trichloride, N₃S₃Cl₃, introduces the thionitrosyl group onto a metal centre during the reaction. Na[CpCr (CO)₃] + (1/3) N₃S₃3Cl₃ • CpCr (CO)₂(NS) An x-ray crystallographic analysis of this complex shows that the thionitrosyl group coordinates essentially linearly to the chromium via the nitrogen atom. A second product formed in this reaction, Cp₂Cr₂ (CO)₄S, possesses a novel Cr-S-Cr linkage which is linear, short, and chemically inert The cations, [(RC₅H₄)Mn(CO)₂(NO)] + (R = H or Me) react with I in acetone at room temperature to produce (RC₅H₄)Mn(CO)₂(NO)I. These species have very labile CO ligand which are readily displaced by Lewis bases to produce (RC₅H₄) - Mn(L) (NO)I [R = H, L = PPh₃ or P(OPh)₃; R = Me, L = PPh3, P(OPh)₃, or P(C₆H₁₁:L)₃]. The reactions of Br-, Cl⁻, and NO₂⁻ with [(RC₅H₄)Mn(CO)2(NO)]⁺ produce the unusual bimetallic compounds (RC₅H₄)₂Mn₂ (NO) ₃X (R == H or Me; X = Cl, Br, or N₂) The compound [CpCr(NO)2]2 abstracts all of the chlorine ligands from SnCl₄, MCl₂ (M = Hg, Sn, or Pb), CpFe-(CO)₂Cl, and Mn(CO)₅Cl in. refluxing thf to form CpCr(NO)₂Cl. The other products are the metals (M), [CpFe(CO)₂]₂, and Mn₂(CO)₁₀, respectively. The chromium dimer also abstracts halogen from vic-dihaloalkanes to produce the corresponding alkenes in good yields. / Science, Faculty of / Chemistry, Department of / Graduate
2

Carbonyl clusters of the iron triad containing nitrosyl and sulphido ligands

Attard, J. P. January 1987 (has links)
No description available.
3

Studies on some platinum metal compounds

Sherman, D. J. January 1987 (has links)
No description available.
4

Transformations of cyclic olefins mediated by tungsten and molybdenum nitrosyl complexes

Buschhaus, Miriam Sarah Anne 11 1900 (has links)
Thermolysis of Cp*W(NO)(CH ₂CMe₃) ₂,CpW(NO)(CH ₂CMe₃)₂, Cp*W(NO)(CH₂SiMe₃)(η²-CPhCH₂), or Cp*W(NO)[CH(Ph)CH₂CH(nPr)CH₂]in cyclic olefins results in the formation of ring-retaining oligomers having lengths up to dodecamers. The main cyclohexene dimer is 3-cyclohexylcyclohexene. A small percentage of oligomers contain neopentyl or CH=CHPh end groups. Turnover frequencies for the Cp*-tungsten precatalysts range from 5.5 to 6.5 mol/h at 100 °C. In room temperature solutions, Cp*Mo(NO)(CH₂CMe₃)₂ generates the alkylidene intermediate [Cp*Mo(NO)(=CHCMe₃)], which couples with cyclic olefins to form cismetallacycles. The isolable cyclopentene-derived cis-metallacycle, Cp*Mo(NO)[cis-η² CH(CH₂)₃CHCHCMe₃], converts in the solid state to the allyl-hydride complex Cp*Mo(NO)(H)(η³-CH(CH₂)3CCHCMe₃). With larger cyclic olefins (cyclohexene through cyclooctene) the initial cis-metallacycles isomerize to trans-metallacycles of the form Cp*Mo(NO)[trans-η²-CH(CH₂)nCHCHCMe₃] (n = 4, 5, 6), and these subsequently convert with loss of dihydrogen to η⁴-diene complexes, Cp*Mo(NO)[η⁴-CHCH(CH₂)n-₁CCHCMe₃]. Thermolysis of the η⁴-diene complexes in cyclohexene results in decomposition of the organometallic complex with small amounts of oligomer formation. Thermolysis of Cp*W(NO)CH₂CMe₃)₂ in cyclic-olefm substrates generates the alkylidene intermediate [Cp*W(N0)(=CHCMe₃)], which couples with cyclic olefins in a manner analogous to the Cp*Mo-system. Tungsten trans-metallacycles are observed by ¹H NMR spectroscopy, but the organometallic subsequently reacts further with loss of the coupled neopentyl-cyclic olefin and coordination of two substrate molecules to form the putative Cp*W(NO)(cyclic olefm)₂ complex. Two additional cyclooctene products are isolated, the 1,4- diene Cp*W(N0)[η⁴-CHCH(CH₂)₅CHCCH(CH₂)₆] and the allyl hydride Cp*W(NO)(H)[η³- CH(CH₂)₆CCCHCH(CH₂)₅], both containing two coupled cyclooctene molecules. A tungsten cis-metallacycle forms with 2,5-dihydrofiiran, but a ring-opened alkoxy-allyl complex forms with 3,4-dihydro-2H-pyran, and 1,2,3,6-tetrahydro-pyridine undergoes N -H bond activation to afford an amido product. CpW(NO)(CH₂CMe₃)₂ produces some oligomers of cyclohexene, but in all other reactions bimetallic decomposition pathways predominate.
5

Transformations of cyclic olefins mediated by tungsten and molybdenum nitrosyl complexes

Buschhaus, Miriam Sarah Anne 11 1900 (has links)
Thermolysis of Cp*W(NO)(CH ₂CMe₃) ₂,CpW(NO)(CH ₂CMe₃)₂, Cp*W(NO)(CH₂SiMe₃)(η²-CPhCH₂), or Cp*W(NO)[CH(Ph)CH₂CH(nPr)CH₂]in cyclic olefins results in the formation of ring-retaining oligomers having lengths up to dodecamers. The main cyclohexene dimer is 3-cyclohexylcyclohexene. A small percentage of oligomers contain neopentyl or CH=CHPh end groups. Turnover frequencies for the Cp*-tungsten precatalysts range from 5.5 to 6.5 mol/h at 100 °C. In room temperature solutions, Cp*Mo(NO)(CH₂CMe₃)₂ generates the alkylidene intermediate [Cp*Mo(NO)(=CHCMe₃)], which couples with cyclic olefins to form cismetallacycles. The isolable cyclopentene-derived cis-metallacycle, Cp*Mo(NO)[cis-η² CH(CH₂)₃CHCHCMe₃], converts in the solid state to the allyl-hydride complex Cp*Mo(NO)(H)(η³-CH(CH₂)3CCHCMe₃). With larger cyclic olefins (cyclohexene through cyclooctene) the initial cis-metallacycles isomerize to trans-metallacycles of the form Cp*Mo(NO)[trans-η²-CH(CH₂)nCHCHCMe₃] (n = 4, 5, 6), and these subsequently convert with loss of dihydrogen to η⁴-diene complexes, Cp*Mo(NO)[η⁴-CHCH(CH₂)n-₁CCHCMe₃]. Thermolysis of the η⁴-diene complexes in cyclohexene results in decomposition of the organometallic complex with small amounts of oligomer formation. Thermolysis of Cp*W(NO)CH₂CMe₃)₂ in cyclic-olefm substrates generates the alkylidene intermediate [Cp*W(N0)(=CHCMe₃)], which couples with cyclic olefins in a manner analogous to the Cp*Mo-system. Tungsten trans-metallacycles are observed by ¹H NMR spectroscopy, but the organometallic subsequently reacts further with loss of the coupled neopentyl-cyclic olefin and coordination of two substrate molecules to form the putative Cp*W(NO)(cyclic olefm)₂ complex. Two additional cyclooctene products are isolated, the 1,4- diene Cp*W(N0)[η⁴-CHCH(CH₂)₅CHCCH(CH₂)₆] and the allyl hydride Cp*W(NO)(H)[η³- CH(CH₂)₆CCCHCH(CH₂)₅], both containing two coupled cyclooctene molecules. A tungsten cis-metallacycle forms with 2,5-dihydrofiiran, but a ring-opened alkoxy-allyl complex forms with 3,4-dihydro-2H-pyran, and 1,2,3,6-tetrahydro-pyridine undergoes N -H bond activation to afford an amido product. CpW(NO)(CH₂CMe₃)₂ produces some oligomers of cyclohexene, but in all other reactions bimetallic decomposition pathways predominate.
6

The action of nitrosyl chloride on hydrocarbons of the methane series

Foote, P. A. January 1928 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1928. / Typescript. With this is bound: Derivatives of para-methoxycinnamic acid / By P.A. Foote. Reprinted from Journal of the American Pharmaceutical Association, vol. XVII, no. 10 (Oct. 1928), p. 958-962. Includes bibliographical references.
7

I. The addition of nitrosyl halides to isobutylene.

Erickson, Wallace Alfred, January 1939 (has links)
Thesis (Ph. D.)--University of Chicago, 1936. / Lithoprinted. "Private edition, distributed by the University of Chicago Libraries, Chicago, Illinois."
8

Transformations of cyclic olefins mediated by tungsten and molybdenum nitrosyl complexes

Buschhaus, Miriam Sarah Anne 11 1900 (has links)
Thermolysis of Cp*W(NO)(CH ₂CMe₃) ₂,CpW(NO)(CH ₂CMe₃)₂, Cp*W(NO)(CH₂SiMe₃)(η²-CPhCH₂), or Cp*W(NO)[CH(Ph)CH₂CH(nPr)CH₂]in cyclic olefins results in the formation of ring-retaining oligomers having lengths up to dodecamers. The main cyclohexene dimer is 3-cyclohexylcyclohexene. A small percentage of oligomers contain neopentyl or CH=CHPh end groups. Turnover frequencies for the Cp*-tungsten precatalysts range from 5.5 to 6.5 mol/h at 100 °C. In room temperature solutions, Cp*Mo(NO)(CH₂CMe₃)₂ generates the alkylidene intermediate [Cp*Mo(NO)(=CHCMe₃)], which couples with cyclic olefins to form cismetallacycles. The isolable cyclopentene-derived cis-metallacycle, Cp*Mo(NO)[cis-η² CH(CH₂)₃CHCHCMe₃], converts in the solid state to the allyl-hydride complex Cp*Mo(NO)(H)(η³-CH(CH₂)3CCHCMe₃). With larger cyclic olefins (cyclohexene through cyclooctene) the initial cis-metallacycles isomerize to trans-metallacycles of the form Cp*Mo(NO)[trans-η²-CH(CH₂)nCHCHCMe₃] (n = 4, 5, 6), and these subsequently convert with loss of dihydrogen to η⁴-diene complexes, Cp*Mo(NO)[η⁴-CHCH(CH₂)n-₁CCHCMe₃]. Thermolysis of the η⁴-diene complexes in cyclohexene results in decomposition of the organometallic complex with small amounts of oligomer formation. Thermolysis of Cp*W(NO)CH₂CMe₃)₂ in cyclic-olefm substrates generates the alkylidene intermediate [Cp*W(N0)(=CHCMe₃)], which couples with cyclic olefins in a manner analogous to the Cp*Mo-system. Tungsten trans-metallacycles are observed by ¹H NMR spectroscopy, but the organometallic subsequently reacts further with loss of the coupled neopentyl-cyclic olefin and coordination of two substrate molecules to form the putative Cp*W(NO)(cyclic olefm)₂ complex. Two additional cyclooctene products are isolated, the 1,4- diene Cp*W(N0)[η⁴-CHCH(CH₂)₅CHCCH(CH₂)₆] and the allyl hydride Cp*W(NO)(H)[η³- CH(CH₂)₆CCCHCH(CH₂)₅], both containing two coupled cyclooctene molecules. A tungsten cis-metallacycle forms with 2,5-dihydrofiiran, but a ring-opened alkoxy-allyl complex forms with 3,4-dihydro-2H-pyran, and 1,2,3,6-tetrahydro-pyridine undergoes N -H bond activation to afford an amido product. CpW(NO)(CH₂CMe₃)₂ produces some oligomers of cyclohexene, but in all other reactions bimetallic decomposition pathways predominate. / Science, Faculty of / Chemistry, Department of / Graduate
9

Synthetic and Electrochemical Studies of Novel Iron Nitrosyl Complexes

Reginato, Nada 08 1900 (has links)
<p> Dinitrosyliron complexes have gained importance as a result of their biological and chemical relevance. Their biological significance stems from the roles exhibited by nitric oxide, including its ability to regulate blood pressure, to act as a biological messenger and because of its involvement in memory storage. Other functions that these dinitrosyliron-based complexes have displayed include their ability to transfer molecular oxygen to alkenes or phosphines, and its use in the polymerization of olefins. One area not yet extended to iron dinitrosyl complexes involves the synthesis of polymeric materials containing a conjugated backbone in the polymer. Thus, the next logical approach was to apply this idea, while investigating their potential to demonstrate unique properties such as optical, redox, and/or conducting behaviour exemplified by other inorganic and organometallic polymeric species. Hence, reactions involving Fe(NO)2(CO)2 and bidentate diphosphine ligands, bis(diphenylphosphino)methane (DPPM), trans-1,2-bis(diphenylphosphino)ethylene (t-DPPEN), 1,1 '-bis(diphenylphosphino) ferrocene (FcP2), bis(diphenylphosphino)acetylene (DPPA) and 1,4- bis(diphenylphosphino)benzene (DPPB) have been investigated. Three types of compounds arose from these reactions: the monometallic system Fe(DPPM)(N0)2(CO) 9, linear dimetallic molecules of the type Fe2(μ-L)(N0)4(CO)2 (L = PPh2CHzPPh2 10, PPh2C≡CPPh2 11, PPh2(p -6H4)PPh2 12, PPhzCH=CHPPhz 13, and PPh2((C5H4)2Fe) PPh2 14), and cyclic dimetallic species of the type Fe2(μ-L)(NO)4 (L = PPh2(p-C6H4)PPh2 15, PPh2CH2PPh2 16, and PPh2C≡CPPh2 17). These systems were isolated and characterized by the use of NMR and IR spectroscopy. The structures of compounds 10, 11, 16 and 17 were also determined by X-ray crystallography. The linear dimetallic compounds, 11, 13 and 14, were treated with tetracyanoethylene (TCNE) to afford compounds of the type Fe2(μ-L)(N0)4(TCNE)2 (L = PPhzC≡CPPh2 18 and PPh2((C5H4)2- Fe)PPh2 19) and [(TCNE)(NO)2Fe(μ-L)[Fe(NO)2(CO)] (L = PPh2CH=CHPPh2 20). These TCNE adducts were probed by means of cyclic voltammetry to investigate their potential redox properties; only compound 18 revealed communication between the two iron centres. </p> <p> Dinitrosyldicarbonyliron, Fe(NO)2(CO)2 and other four-coordinate dinitrosyliron systems have been extensively examined in terms of nucleophilic substitution, including the effects of both hard and soft bases. These findings prompted us to ask whether electrophiles attack dinitrosyliron complexes. Hence, Fe(NO)2(CO)2 1, and also the phosphine complexes Fe(NO)2(CO)(PPh3) 21, and Fe(NO)2(PPh3)2 22, have been treated with a variety of electrophiles (HCl, SiMe3Cl, Et30^+SbCl6-, trifluoroacetic acid (TFA) and trifluoromethanesulfonic acid (TFSA)) to probe the nucleophilic character of the iron centres. Moreover, another approach involved examining the nucleophilic nature of the iron nitrosyl salts, [PPN^+][Fe(CO)3(NO)], 24 and [N(Bu)4+][Fe(C0)3(NO)], 25. </p> / Thesis / Master of Science (MSc)
10

STRUCTURAL STUDIES OF THE BINDING OF SMALL MOLECULES TO TRANSITION METALS

Haller, Kenneth James January 1978 (has links)
No description available.

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