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Showing 1 to 13 of 13 for “"benzoin"”.
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Preparation of Novel Carbenes and their Catalytic Application to the Cross-Benzoin, Aza-Benzoin and Stetter Reactions
… found to induce chemoselectivity in the cross-benzoin between aromatic and aliphatic aldehydes. Use of these catalysts gave rise to predominantly one cross-benzoin product which could be isolated in good to excellent yield (68-99%). Consistently high chemoselectivity was realized across a wide …
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The oxidation of benzoin and related molecules in glacial acetic acid
Thesis (M.S.)--Michigan State University of Agriculture and Applied Science. Dept. of Chemistry, 1961
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The Utilization of Carbene Catalysis and Different Synthetic Strategies for Sydnone Construction
Here, the synthesis of benzoin was conducted using carbene precatalyst bis(amino)cyclopropenylidene (BAC-H) with multiple different bases that are used in literature. It was determined that the combination of bases sodium hydride and KHMDS provided moderate yields of benzoin. Further optimization …
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Elucidation Of Chiral Recognition Mechanisms Of Solutes By Amylose Tris[(s)-Alpha-Methylbenzylcarbamate] Sorbent
… tris[(S)-alpha-methylbenzylcarbamate], for benzoin (B) enantiomers were first studied. The HPLC data for benzoin with pure n-hexane as the mobile phase have been obtained. The behavior of sorbent-solute-hexane systems can be interpreted by considering only sorbent solute two-component …
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Entwicklung einer robusten chemo-enzymatisch dynamisch kinetischen Racematspaltung für die nachhaltige Synthese chiraler α-Hydroxyketone
… dynamisch kinetischen Racematspaltung (DKR) von Benzoin, was im Rahmen dieser Studie durch zwei Teilprojekte realisiert werden sollte: (1) Die Optimierung der kinetischen Racematspaltung sowohl auf der Seite der Biokatalysatorentwicklung als auch in der Prozessparameteroptimierung und (2) die …
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Dearomative reduction of arenes through the use of arenophiles & studies towards the synthesis of cardiotonic steroids calotropin and calactin
… strategy which utilizes a NHC-catalyzed benzoin condensation, and Pd-catalyzed nucleophilic dearomatization of a phenol is described. Also described, is the semisynthetic strategy towards calotropin from estrone, where the aromatic A ring is dearomatized to introduce a C1 fragment at the …
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Design and Synthesis of Chiral Triazolium and Thiazolium Salts Incorporating Hydrogen-Bonding Motifs as Organocatalysts
The benzoin condensation is the rst reported example of organocatalysis, and has been studied and used in organic synthesis for over 200 years. Originally catalysed by the cyanide anion, the reaction can also proceed with thiamine as a catalyst. Since then, many N- heterocyclic carbene (NHC) …
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Synthesis, study and application of silyl ketene imines in Lewis base catalyzed carbonyl addition
… reactions and allow for the preparation of cross-benzoin and glycolate-aldol products in high yield and with exceptional diastereo- and enantioselectivities.
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Contributions to the chemistry of higher-coordinate Silicon : synthesis, structure, and stereodynamics of new Silicon(IV) complexes with SiO2N2C, SiO4C, or SiO6 skeletons
… a remarkable Si–C cleavage reaction with benzoin. To investigate the dynamic behavior of the known zwitterionic Lambda5Si-silicate 18 in solution, VT 1H NMR experiments in CD2Cl2 were performed in the temperature range –100 °C to 23 °C.The hexacoordinate silicon compounds 19–22 containing …
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Utilization of Biomass Derived Furans in Value-Added Organics and Heterogeneous Oxorhenium Catalysts for Deoxydehydration of Diols
… using the N-heterocyclic carbene catalyzed benzoin condensation. Here, green methods are focused on with the ultimate goal of realizing the two-step process of producing furfural and subsequently performing the homocoupling. The C10 product, furoin, serves as a good platform for the …
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Benign Catalysis and Expansion of Cyclobenzoins
Cyclobenzoins are a fledgling class of macrocycles first reported by the Miljanić group in 2015. Since the first reports, several modifications to the original two compounds, cyclotribenzoin and cyclotetrabenzoin, have been reported, but no developments on the production have been reported. Whether …
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A polarographic study of the reduction of unsymmetrical benzils.
This investigation applied the techniques of polarography and controlled potential electrolytic reduction to the study of a series of unsymmetrical benzils. Eleven unsymmetrical benzils were synthesized and studied in 50% ethanol-water (by volume) solvent systems buffered at pH 1, 5, and 13. The …
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Beiträge zur Chemie des höherkoordinierten Siliciums: Synthese, Struktur und Eigenschaften neuer Silicate mit SiO 3 C 2 -, SiO 4 C -, SiO 5 - und SiO 6 -Gerüst, Beiträge zur Chemie des tetrakoordinierten Siliciiums: Synthese, Struktur und Eigenschaften von Silanen, Silanolen und Siloxanen
… [(2,2,6,6-tetramethylpiperidino)methyl]-silan mit Benzoin gelang die Synthese von 7. Mit Verbindung 8 — dargestellt durch Umsetzung von Dimethoxy(methyl)[(2,2,6,6-tetramethylpiperidino)methyl]silan mit Brenzkatechin — gelang erstmals die Synthese eines zwitterionischen l5Si-Silicates mit …