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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.
71

Preparation of new cyclopentadienyl molybdenum carbonyl complexes

Bukasa, Kabongo Joachim 22 August 2012 (has links)
M. Sc. / This study comprises the preparation and characterisation of new cyclopentadienylmolybdenum carbonyl complexes. In addition, an unique isomeric equilibrium as well as the new packing pattern of the known compound of cyclopentadienyltricarbonylmolybdenum bromide is also described. The cyclopentadienylmolybdenum carbonyl complexes have been prepared from precursors of the type [CpMo(C0)3X] which reacts with alkyllithium reagent to -afford [CpMo(CO)3R] compounds. [CpMo(C0)3I] reacts with phenylacetylide lithium to form [Cp(C0) 3MoC-CP11] (1). The X-ray crystal structure of compound 1 has been determined and reveals that the length of the triple bond is somewhat shorter than any of the other known acetylide complexes. Treatment of 1 with the electrophiles CF3SO3CH3 or (CH3)2SO4 gives the cationic complex [Cp(C0)3Mo=C=C(CH3)(Ph)r CF 3S03" (4). [CpMo(C0)3I] reacts with 1,3-dithianyllithium to form [Cp(C0)3Moe(H)SCH2CH2C1121 (2) which can easily be deprotonated on the coordinated carbon. [CpMo(C0) 3I] also reacts with methyllithium to form [CpMo(CO)3CH3] (3) which is a known compound. The reaction of CS2 with 1 which occurs by a (2 + 2) cycloaddition affords [Cp(CO)3MoC=C(Ph)C(=S)S] (5). As we could not alkylate this CS 2 adduct, additional studies with molybdenum compounds in which a CO ligand has been substituted with PPh 3 and PMe3 have been carried out. [CpMo(C0)3I] reacts with PPh3 to form [CpMo(CO)2(PPh3)I] (6), a stable compound, known and well characterised. The compound 6 also reacts with phenylethynyllithium to form [Cp(C0)2(PPh3)MoCE---CPh] (7). Treatment of 7 with CS2 leads to [Cp(C0)2(PPh3)MoC=C(Ph)C(=S)] (8). [CpMo(C0)3I] reacts with PMe3 to yield two isomers [CpMo(CO)2(PMe3)I] (cis-9) and (trans-9). These two isomers were isolated and we observed that in solution the cis isomer was slowly transformed into the trans isomer which indicated the existence of an isomeric equilibrium. Cis-9 react: with phenylethynyllithium to form [Cp(C0)2(PMe3)MoCCP11] (11). Finally, during unsuccessful attempts to react the dimeric compound [CpMo(CO)3]2 with alkyl and aryllithium, the known compounds [11 5-CpMo(C0)3C1] and [re-CpMo(C0)3Br] (12) were produced in crystalline form. The X-ray crystal structure of the neutral complex 12 has been determined and the molecular structure has bond distances and angles very similar to the literature values of the same compound. However, the compound 12 exhibits a different packing pattern in the unit cell.
72

Synthesis of phenolic natural products

Chaly, Thomas. January 1984 (has links)
No description available.
73

Isolation and identification of acidic and neutral carbonyl compounds in various cheese varieties /

Bassett, Emmett Washington January 1956 (has links)
No description available.
74

The controlled thermal decomposition of cellulose nitrate : carbonyl compounds /

Arsenault, Guy Pierre January 1958 (has links)
No description available.
75

Synthesis of anionic and neutral derivatives of H₂Os₃(CO)₁₀.

Kennedy, Steven January 1981 (has links)
No description available.
76

Relations between photodecomposition modes and molecular structure in a series of carbonyl compounds /

Nicol, Charles Henry January 1965 (has links)
No description available.
77

Polynuclear transition metal carbonyls containing sulfur and phosphorus /

Pollick, Philip John January 1969 (has links)
No description available.
78

Studies of manganese(I) carbonyl complexes containing \"hard\" donor atoms /

Parker, Paula Jacoby January 1969 (has links)
No description available.
79

Part I. Synthesis and reactions of carbonyl sugars. Part II. Synthesis and modification of nucleosides /

Baker, David C. January 1973 (has links)
No description available.
80

Some photochemical reactions of dimanganesedecacarbonyl /

Hallock, Stephen A. January 1974 (has links)
No description available.

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