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Thesis (Master)--İzmir Institute of Technology, İzmir, 2004. / Includes bibliographical references (leaves. 29-31).

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xxi, 215 p.; also includes graphics (some col.). Includes bibliographical references (p. 209-215).

Thesis (Ph. D.)--University of Texas at Austin, 2005. / Vita. Includes bibliographical references.

The reactions of (ɳ⁵-C₅R₅)M(NO)(CO)₂ (R = H, Me; M = Mo, W) with PCl₅ result in the formation of the corresponding (ɳ⁵-C₅R₅)M(NO)(Cl)₂ products in high isolated yields (85-95%). These products have been fully characterized by conventional analytical and spectroscopic techniques including an X-ray crystallographic study of [ɳ⁵-C₅Me₅)Mo(NO)(Cl)₂]₂. Alkylation of the (ɳ⁵-C₅R₅)W(NO)(Cl)₂ compounds with Grignard reagents results in the formation of the corresponding complexes, (ɳ⁵-C₅R₅)W(NO)(R')₂ (R = H, Me; R' = CH₂CM₃, CH₂CM₂Ph: R = Me; R' = p-C₆H₄Me, Ph). An electrochemical study of (ɳ⁵-C₅H₅)W(NO)(CH₂CMe₃)₂, (ɳ⁵-C₅H₅)W(NO)(CH₂CMe₂Ph)₂, and (ɳ⁵-C₅Me₅)W(NO)(p-C₆H₄Me)₂ shows 2 successive, chemically reversible, one electron reductions in THF for each complex. The complexes (ɳ⁵-C₅R₅)W(NO)(R')₂ (R = H; R' = CH₂CMe₃, CH₂CMe₂Ph: R = Me; R' = CH₂CMe₂Ph,p-C₆H₄Me) react with 1 atm of CO resulting in the formation of the singly inserted products (ɳ⁵-C₅R₅)W(NO){C(O)R'}(R') in good yields, presumably via initial CO coordination. These acyl complexes have been completely characterized by conventional techniques. The IR and NMR spectroscopic properties of these complexes are indicative of an ɳ²-acyl coordination mode for all of the acylalkyl and acylaryl products. Under 6 atm of CO the (ɳ⁵-C₅H₅)W(NO)(R')₂ (R' = CH₂CMe₃, CH₂CM₂Ph) complexes are doubly carbonylated to form the corresponding (ɳ⁵-C₅H₅)W(NO){C(O)R'}₂ products. Furthermore, (ɳ⁵-C₅Me₅)W(NO){C(O)p-C₆H₄Me}(p-C₆H₄Me) reacts to form (ɳ⁵-C₅Me₅)W(NO)(CO){C(O)p-C₆H₄Me}(p-C₆H₄Me) under 6 atm of CO, but there is no evidence for the formation of a bis(acyl) product. A preliminary X-ray crystallographic investigation of (ɳ⁵-C₅H₅)W(NO){C(O)CH₂CMe₂Ph}₂ reveals the presence of one ɳ²-acyl ligand and one ɳ¹acyl ligand. The ¹H and ¹³C{¹H} NMR spectra of the (ɳ⁵-C₅H₅)W(NO){C(O)R'}₂ compounds exhibit signals for only one type of acyl ligand, indicating that the complexes are stereochemically non-rigid in solution through a process which averages the signals for the ɳ¹and ɳ³- acyl ligands. The bis(benzyl) complexes, (ɳ⁵-C₅R₅)M(NO)(CH₂Ar)₂ (R = H, Me; M = Mo, W; Ar = Ph, p-Tol), react with HCl to form (ɳ⁵-C₅R₅)M(NO)( ɳ²-CH₂Ar)(Cl) complexes. These complexes have been reacted with Grignard reagents, R'MgCl, to form the corresponding (ɳ⁵-C₅R₅)M(NO)( ɳ²-CH₂Ar)(R') (R' = CH₂SiMe₃, CH₂CMe₃, p-Tol) products. The benzyl ligand in all of these complexes is coordinated in an ɳ²-fashion, similar to that seen in the solid-state molecular structures of the bis(benzyl) precursors. The coordination mode of the benzyl ligands has been confirmed by solid-state molecular structure determinations of the representative examples (ɳ⁵-C₅Me₅)Mo(NO)(CH₂Ph)(Cl) and (ɳ⁵-C₅Me₅)Mo(NO)(CH₂Ph)(CH₂SiMe₃). The ¹H and ¹³C{¹H} NMR spectroscopic data for all of the complexes are discussed, with focus on the diagnostic characteristics for the ɳ²-benzyl ligand. A possible qualitative interpretation for the symmetric ɳ²-bonding mode in these complexes is presented. The (ɳ⁵-C₅Me₅)M(NO)( ɳ²-CH₂Ph)(Cl) (M = Mo, W) complexes react with AgBF₄ in CH₃CN to form electrophilic complexes of the type [(ɳ⁵-C₅Me₅)M(NO)( ɳ²-CH₂Ph)(NCCH₃)]BF₄. The solid-state molecular structures of these complexes are discussed and contrasted with those found for the neutral ɳ²-benzyl complexes. The reaction of racemic AgO₂CCH(Et)(Ph) with the (ɳ⁵-C₅R₅)M(NO)( ɳ²-CH₂Ph)(Cl) (R = H, Me; M = Mo, W: R = H; M = Mo) compounds forms the corresponding diastereomeric (ɳ⁵-C₅R₅)M(NO)( ɳ¹-CH₂Ph)(O₂CCH(Et)(Ph)) products. The ɳ¹ coordination of the benzyl ligand and bidentate coordination of the carboxylate ligand are established by the IR, ¹H, and ¹³C{¹H} NMR spectroscopic data for these products. A mixture of two diasteromeric products is demonstrated by the ¹H and ¹³C{¹H} NMR spectroscopic data and initial attempts to separate these diastereomers by crystallization are described. / Science, Faculty of / Chemistry, Department of / Graduate

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.

Includes bibliography.

Thesis (M.M.S.E.)--University of Delaware, 2006. / Principal faculty advisors: Robert L. Opila and Robert W. Birkmire, Dept. of Materials Science & Engineering. Includes bibliographical references.