Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 19 of 19 for “"Carbene complexes"”.
-
Synthesis and application of rhodium(I) Fischer carbene complexes
In this study, novel rhodium(I) carbene complexes were synthesized and fully characterized via a carbene ligand transfer methodology from Group 6 Fischer carbene complex precursors and subsequent ligand modification. The classic Fischer route was followed towards the isolation of mono- and …
-
Fischer and N-heterocyclic carbene complexes of Group (VII) transition metals
… application of Fischer- and N-heterocyclic carbene (NHCs) complexes of the group VII transition metals were investigated. By using density function theory calculations, the structural and electronic parameters could be elucidated and the fundamental bonding interactions between the carbene …
-
Synthetic and catalytic studies of Group 11 N-heterocyclic carbene complexes
… and reactivity of two-coordinate Group 11 metal complexes, supported by N-heterocyclic carbene (NHC) ligands. The NHC ligand was found to stabilize monomeric, terminal fluoride complexes of copper, silver and gold, the last representing the first isolable gold(I) fluoride. These complexes were …
-
Synthetic investigation of Mn(I) and Re(I) N-heterocyclic carbene complexes
… approaches towards the preparation of novel NHC complexes of low valent rhenium and manganese transition metals. Diverse methods of synthesis were studied. The direct approach, in which the ylidene obtained from deprotonation of 1,3-bis(2,4,6- trimethylphenyl)imidazolium chloride was added to the …
-
Development of Cobalt and Nickel N-Heterocyclic Carbene Complexes for Cross-Coupling Reactions
… development of pre-formed cobalt and nickel NHC complexes analogous to their Pd counterparts would improve reactivity in Negishi, Suzuki-Miyaura, and Buchwald-Hartwig amination cross-coupling reactions. Co(IPent)Cl2(Pyr), Co(IPentCl)Cl2(Pyr), and Co2IPr2(OAc)4 were prepared, identified by X-ray …
-
Synthesis of alkyl- and poly(ethylene)glycol linked bis-dioxocyclams from bis-chromium carbene complexes
Alkyl-linked bis-chromium carbene complexes have been prepared via deprotonation and α-alkylation of (methoxy)(methyl) chromium carbene complexes using l,n-bis-triflates as electrophiles. These bis-carbene complexes were then photolyzed with N-protected imidazolines to give protected bis-azapenams. …
-
Synthesis and application of Fischer carbene complexes of group 6, 8 and 9 transition metals
A range of novel Fischer carbene complexes (FCCs) of group 6 (Cr and W), 8 (Fe) and 9 (Co) metals was prepared using the classical Fischer route, and their electronic and steric properties evaluated. For W(0) and Cr(0), 2,3´-bithiophene (2,3ʹ-BT) was employed as carbene ligand substituent. A range …
-
Studies of the Coordination Chemistry and Catalytic Activity of Rhodium and Ruthenium N-Heterocyclic Carbene Complexes
The side-on dioxygen adducts of N-heterocyclic carbene (NHC) containing rhodium complexes, [ClRh(IPr)2(O2)] and [ClRh(IMes)2(O2)], previously synthesized in our laboratories possess a square planar geometry and O-O bond lengths of 1.323(3) and 1.341(4) Å, respectively. Both of these attributes are …
-
Quantum chemical investigation of electron delocalization patterns during photoexcitation in Fischer carbene complexes: a theoretical study
Electron (de)localization is notoriously difficult to study. However, it is critically important for fundamental understanding of various photophysical and photochemical processes, including those that occur during light-harvesting in various solar energy devices. This work presents the novel …
-
Design and modification of rhodium and iridium N-heterocyclic carbene complexes for asymmetric transfer hydrogenation and antimicrobial activity
… the wide utility of noble metal N-heterocyclic carbene (NHC) complexes. The first project details the design of iridium NHC amino acid complexes for asymmetric transfer hydrogenation (ATH) of prochiral ketones. Iridium(I) bis-NHC complexes were found to undergo oxidative addition with a variety …
-
Chloromethyl and methoxymethyl transition metal complexes : an investigation into their synthesis and reactivity
Transition metal methoxymethyl and chloromethyl complexes may be versatile starting materials for the synthesis of several types of new complexes, including hydroxymethyl and carbene complexes, respectively [LₙMCH₂OH] and [LₙMCH₂]⁺ (M=transition metal, L=ligands). Hydroxymethyl and carbene …
-
The synthesis of sterically demanding ligands and examples of their copper complexes
… analogs. Two new copper(I) N-heterocyclic carbene complexes containing the 2,4,6,2",4",6"-hexaisopropyl-1,1':3',1"-terphenyl moiety have been synthesized and isolated. The LCuCl complex (92% isolated yield) was made via a one-pot synthesis from the corresponding imidazolinium …
-
SUSTAINABLE CATALYSIS VIA IRON AND ZINC COMPLEXES: FROM TUNABLE METALLATE SYSTEMS TO PHOTOCHEMICAL REACTIVITY
This thesis investigates the use of iron and zinc complexes as sustainable catalysts for transformations of small, strained heterocycles in the field of carbon dioxide valorization, as well as the synthesis of iron complexes as catalysts for photochemical oxidation. In the first part of the work, …
-
Aplicaciones derivadas de la fotoquímica de O-aciloximas
… irradiated in the presence of alkynyl Fischer carbene complexes, which constitutes the first example of a photochemically driven reaction of this kind. When the radical participates in a 1,4- addition to alkynylcarbene complexes 5-aza-1-metalla-1,3,5-hexatriene where obtained, while the 1,2 …
-
Rigid Ruthenium PCcarbeneP Complexes for Small Molecule Activation, Hydrogenation, and Dehydrogenation
… a series of pincer ligands that form metal-carbene complexes. These metal-carbenes have shown to be competent in a wide array of small molecule activations. Previous optimizations show that the planar anthracene-based ligands are especially stable. Additionally, ruthenium catalysts have had …
-
Diastereoselective Lithiation-Substitution of N-Silyl-Protected-(S)-Tetrahydro-1H-pyrrolo[1,2-c]imidazole-3(2H)-ones and Applications of Their Derivatives
… as NHC precursors for synthesis of corresponding complexes.
-
Diastereoselective Lithiation-Substitution of N-Silyl-Protected-(S)-Tetrahydro-1H-pyrrolo[1,2-c]imidazole-3(2H)-ones and Applications of Their Derivatives
… as NHC precursors for synthesis of corresponding complexes.
-
Synthetic, Structural and Thermochemical Studies of N-Heterocyclic Carbene (NHC) and Tertiary Phosphine Ligands in the Ni(CO)2(L)x (L-PR3, NHC) Systems
Carbonyl complexes of Ni(0) incorporating two N-heterocyclic carbenes of the type Ni(CO)2(NHC)2 (NHC = ICy [N, N'-bis(cyclohexylimidazol)-2-ylidene], IMes [N, N'- bis(2, 4, 6-trimethylphenyl)-imidazol)-2-ylidene]) have been prepared. The complexes Ni(CO)2(ICy)2 (8) and Ni(CO)2(IMes)2 (9) have been …
-
Organometallic and coordination chemistry of (Tetramethylcyclobutadiene)cobalt sandwich and halfsandwich complexes
… (Cb*Co) tris(ligand) complexes [Cb*Co(L)3]+. An improved synthesis of the starting materials [Cb*Co(CO)3]BF4, Cb*CoI(CO)2 and [Cb*Co(C6H6)]PF6 was developed. Photolysis of [Cb*Co(C6H6)]PF6 in acetonitrile produced [Cb*Co(NCMe)3]PF6. Alternatively, the tris(acetonitrile) …