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 20 of 20 for “"Stille-coupling"”.
-
Palladium -catalyzed synthesis of carbazole derivatives and formal total syntheses of several naturally occurring carbazole alkaloids
… palladium-catalyzed reactions, an intermolecular Stille coupling followed by an intramolecular reductive N-heteroannulation. For example, 1,2-dihydro-4(3H)-carbazolone was prepared in good isolated yield (74%) by the reductive cyclization of 2-(2-nitrophenyl)-2-cyclohexen-1-one using Pd(dba)2 (6 …
-
A base modulated synthesis of indoles and quinolines, an expedient synthesis of salviadione, and chemoselective couplings en route to indoles and pyrroloindoles
… of chemoselectivity in Kosugi-Migita-Stille coupling reactions provided the basis for the synthesis of isomeric pyrroloindoles through palladium-catalyzed reductive double N-heteroannulation of dinitro-dialkenyl benzenes.
-
Synthesis of unnatural analogues of narciclasine: Chemoenzymatic synthesis of 2-epi-1-hydroxymethylnarciclasine
… on chemoenzymatic dihydroxylation of an arene, Stille coupling, and an intramolecular Heck reaction to affect key transformations. The synthesis of the targeted C-1 analogues addresses a gap in literature where few narciclasine analogues have been prepared, with no C-1 homologues existing to …
-
Novel synthetic methodology employing organosulfur chemistry in the synthesis of chalcone derivatives
… dienophiles, and dipolarophiles, and can undergo Stille coupling making them highly versatile synthetic intermediates. They can also undergo sulfur oxidation enabling further functionalisation. The first chapter is a literature review of Stille coupling involving b-haloenone systems, including …
-
Synthesis of Substituted Bacteriochlorins
… by bromination at the β-position in 22% yield. Stille coupling of BC-Br3OMe5Br13 to introduce a formyl group was performed in 30% yield. Two TIPS-ethynyl groups were also installed on BC-Br3OMe5Br13 in 4.7% yield.
-
Functional polybithiophenes: Novel syntheses approaches, characterization and application aspects
… polycondensation process based on a modified Stille coupling reaction. This polymerization methodology was investigated with the use of various aryl monomeric units. This polycondensation process uses hexabutylstannane, Bu3SnSnBu3, to react with dibrominated aryl monomers in the presence of a …
-
Aplikace substituovaných pyranonů v chemii dendralenů a totální syntéze přírodních látek
… of two palladium- catalyzed reactions, Migita-Stille coupling and Tsuji-Trost allylic transposition. The products obtained were applied in the synthesis of cross-conjugated heterocyclic [3] and [4]dendralenes, providing structurally complex mono- to tris-cycloadducts with a suitable dienophile …
-
Towards the total syntheses of aspidospermidine and aspidofractinine: the curious chemistry of the indolinyl radical
… The second route features a highly efficient Stille coupling and a Wittig olefination. Attempts to effect a critical radical cyclisation reaction are also discussed. The chemistry of the C2 indolinyl radical is investigated, in particular the influence of the C3 indolinyl substitution upon the …
-
Pyrrolo[2,3-d]pyrimidine-based π-conjugated fluorophores with 1,2,3-triazole and ethynyl linkers: synthesis and photophysical properties /
… 650 nm. A comparative study of Sonogashira and Stille reactions as well as Suzuki and Stille reactions for the introduction of alkynyl and aryl moieties onto pyrrolo[2,3-d]pyrimidine has been carried out. The synthesis of pyrrolo[2,3-d]pyrimidine oligoarylenes bearing different alkynyl and aryl …
-
Pirolo[2,3-d]pirimidino π-konjuguotų fluoroforų, turinčių 1,2,3-triazolo ir etinil jungtukus, sintezė ir fotofizikinės savybės /
… 650 nm. A comparative study of Sonogashira and Stille reactions as well as Suzuki and Stille reactions for the introduction of alkynyl and aryl moieties onto pyrrolo[2,3-d]pyrimidine has been carried out. The synthesis of pyrrolo[2,3-d]pyrimidine oligoarylenes bearing different alkynyl and aryl …
-
Novel palladium-catalyzed synthesis of 3-substituted indoles and its application toward the total synthesis of indolactam V
… Various 2-nitrostyrenes were prepared via Stille coupling of 2-tributyl stannyl-2-propenoic acid ethyl ester with substituted 2-bromo-l-nitrobenzenes. Alternatively, sequential vicarious nucleophilic substitution of substituted nitrobenzenes and Knoevenagel condensation with formaldehyde …
-
I. Radical Cyclizations Mediated by Transition Metal Hydrides II. Study toward the Total Synthesis of Pluraflavin A III. Cytoprotective Polyacetylenes Inspired by Panaxytriol
… the attachment of the C-glycosidic residue by Stille coupling. Subsequent stereoselective glycosylation reactions appended the O-glycosidic residues. The current approach furnished an advanced intermediate with all of the functionality of the target, albeit in protected form. The third part of …
-
Studies Towards the Total Synthesis of the Chivosazoles
… of the three key fragments A, B and C, their coupling reactions and subsequent modifications for assembling the backbone of chivosazole F. Paterson boron aldol methodology and Evans-Tishchenko reduction were utilised to construct the 1,4-syn and 1,3-anti stereochemical relationships within …
-
Borafluorenes and polyborafluorenes boron doped varients of fluorene
… further functionalization via Yamamoto and Stille coupling reactions. This incorporation of boron into a conjugated system imparted Lewis acidic and electron deficient properties into a conjugated system. It is our hope that this will dope fluorene and create novel n-type semiconductors. A …
-
Synthesis of Crowded Tolanes: Models for Molecular Recognition
… intramolecular noncovalent interactions. The Stille cross-coupling reaction allowed synthesis of both arylacetylenes and tolanes from aryl iodides. The Stille reaction is usually slow for electron rich aryl iodides (such as these aryl iodides that are substituted resorcinol derivatives). …
-
Synthesis and reactivity of alpha-thio-beta-chloroacrylamides and alpha-thio-beta-chloroenones
… included nucleophilic additions and Stille cross-coupling at the β-carbon. Chapter 1 reviews the literature relevant to the research conducted, and focuses in particular on the synthesis of β-chloroenones and related unsaturated carbonyl compounds. The synthesis of chalcone compounds …
-
Amphiphile Phosphane für die Anwendung in neuen polaren Medien
… prepaired by Kosugi-Stille coupling between 2-tri-n-butyl-stannyl-1-methylimidazole and 4-fluoroiodobenzene. Selective N-protonation or N-quarternisation affords the corresponding imidazolium phosphines. Base catalyzed Anti-Markovnikov addition of PH functionalized …
-
Synthesis and Characterization of Siloles, Silole-Containing Polymers and Photoswitchable Polymer Brush
… applicable for various palladium catalyzed cross-coupling reactions. In cases where the preparation of reactively functionalized siloles were unsuccessful by our method, we were able to accomplish the synthesis in one additional step; nevertheless, our method is still advantageous compare to the …
-
NEW NCN-PLATINUM(II) COMPLEXES WITH LUMINESCENT PROPERTIES
… in different ways: from a Suzuki-Miyaura coupling of 1,3,5-tribromobenzene with the suitable aryl-boronic acid in the case of L1-L4; from 1,3-dibromo-5-fluorobenzene reacting with carbazole for L5; from a Stille coupling of tribromobenzene and 2-SnBu3-thiophene for L6. Once obtained the …
-
Asymmetrische Synthese von Stigmolon und Untersuchungen zur asymmetrischen Synthese von (-)-Cytoxazon und Galbonolid A und B
… steps an enzymatic reduction, Takai-, Wittig-, Stille- and ditin-Stille-reaction, an Enders-alkylation and a 1,2-addition using directing groups. So far two of the four stereogenic centers and all double bonds were combined in a ten-membered building block of the 14-membered ring structure of …