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 43 for “"Nucleophilic Aromatic Substitution"”.
-
Nucleophilic aromatic substitution of metallabenzenes
… can undergo a new benzenelike reaction - nucleophilic aromatic substitution of hydrogen (SN H) (Scheme 0-1). In this process, the nucleophile (Nu) first attacks the cationic metallabenzene (A) at the γ position to the neutral metallacyclohexadiene compound (B). Oxidation with an external …
-
PART I PREPARATION OF NOVEL LACTONES AND THEIR PRECURSORS DERIVED FROM METHYL SALICYLATE PART II NUCLEOPHILIC AROMATIC SUBSTITUTION IN A DINITROSALICYLIC LACTONE WITH RING OPENING AND ELIMINATION VIA MEISENHEIMER INTERMEDIATES
… described. The influence of substituents on the aromatic nucleus in affecting ring closure reactions was examined. Experimental results show that ring closure is enhanced when nitro groups are incorporated in the aromatic ring. Investigations were conducted in the preparation of compounds …
-
Interactions of Nitrated Aromatics With Electron Rich Species: Chiral and Achiral
… the development of the first enantioselective nucleophilic aromatic substitution reactions.
-
Utilization of Rationally Designed Small Molecule Chiral Selectors in Novel Enantioselective Processes
… racemic amides containing electron-deficient aromatic moieties are described. The method revolves around forming Meisenheimer adducts which are stabilized by quaternary ammonium salts in a nonpolar medium. When run in the presence of a chiral selector, one enantiomer is effectively shielded …
-
Metalation of the Di- and Tri-Methoxybenzenes
… the 1,2,3-system affords an interesting nucleophilic aromatic substitution reaction. This autocatalytic mode of ortho-metalation offers additional insight into the controversy regarding the participation of a dimer intermediate in the mechanism of the directed ortho-metalation reaction.
-
Synthesis of pyridines via [4 + 2] cycloadditions of vinylallenes with azadienophiles
… elaboration of these 2- sulfonylpyridines via nucleophilic aromatic substitution reactions. Overall, annulation strategies based on [4 + 2] cycloadditions of vinylallenes with azadienophiles have been developed for the preparation of highly substituted pyridines in an efficient, convergent, and …
-
Synthesis, properties, and modifications of engineering polymers
… structures were systematically synthesized via nucleophilic, aromatic substitution reactions using the potassium carbonate/N-methylpyrrolidone synthesis route. In particular, deuterated poly(arylene ether sulfones) were synthesized in order to investigate molecular motion via deuterium NMR. The …
-
The SRN1 reactivity of halobenzenesulfonamides and related compounds
An investigation of the application of nucleophilic aromatic substitution by the SRN 1 mechanism of halobenzenesulfonamides and related compounds towards the synthesis of 1,2-benzothiazine I,I-dioxides is reported. 3-Substituted and 3,4- disubstituted 2<i>H</i>-l,2-benzothiazine l,l-dioxides were …
-
Synthesis of poly(arylene ether sulfone)-polyimide segmented copolymers
… sulfone) oligomers have been synthesized by nucleophilic aromatic substitution using potassium carbonate as base and N-methyl pyrrolidinone (NMP) as solvent. m-Aminophenol was used as an endcapper to control the molecular weight of the oligomers and to provide functional amine termination. …
-
Synthesis of Chiral Benzimidazolylidenes from 1,10-Phenathrolines and 1,10-Phenathroline-2,9-dione /
… the 2- and 2,9- position of phenanthroline by nucleophilic aromatic substitution, followed by a reduction-resolution sequence; and 3) use of the protected octahydrophenanthroline as a substrate for chiral induction a to nitrogen.
-
Synthesis and Characterization of Phosphorus Containing Poly(arylene ether)s
… thermoplastics. Phosphorus containing activated aromatic dihalides and bisphenols were synthesized in high purity. These monomers were successfully polymerized via nucleophilic aromatic substitution to afford high molecular weight polymers. It was determined that by incorporating the phosphine …
-
Macrocyclic Monomers: Synthesis, Characterization and Ring-opening Polymerization
… large number of macrocycles were synthesized by nucleophilic aromatic substitution cyclization reactions under pseudo-high dilution conditions. Pure individual macrocycles as well as cyclic mixtures were characterized by NMR, HPLC, GPC, FABMS, MALDI-TOF-MS, DSC and TGA. Comparison study suggests …
-
Potential Prodrugs of the Neuronal Nitric Oxide Synthase and Monoamine Oxidase Inhibitor 7-Nitroindazole and Structurally Related Compounds
… have led to a detailed description of the nucleophilic aromatic substitution reactions between 4-chloro-1-methylpyridinium iodide and the indazolyl reactants that were employed as the initial step in the synthesis of the target compounds. The MAO-B substrate and inhibition properties of …
-
Synthesis and Characterization of Hydrophilic-Hydrophobic Disulfonated Poly(Arylene Ether Sulfone)-Decafluoro Biphenyl Based Poly(Arylene Ether) Multiblock Copolymers for Proton Exchange Membranes (PEMs)
… and hydrophilic telechelic oligomers via a nucleophilic aromatic substitution mechanism. The hydrophilic blocks were based on the nucleophilic step polymerization of 3,3′-disulfonated, 4,4′-dichlorodiphenyl sulfone with an excess 4,4′-biphenol to afford phenoxide endgroups. The hydrophobic …
-
Synthesis and basic characteristics of segmented poly(arylene ether sulfone)-poly(arylate) copolymers
… thermoplastic segment was based on various all aromatic poly(arylene ether sulfooes) derived from the nucleophilic aromatic substitution reaction between hydroquinone, biphenol, and dichlorodiphenylsulfone. This reaction was conducted in the presence of potassium carbonate and anhydrous aprotic …
-
Synthesis and characterization of triphenylphosphine oxide containing monomers and high performance polymeric materials
… subsequently incorporated into high performance aromatic polyimides, polyamides, copolysiloxane-poly(aryl-imide) randomly segmented copolymers, and epoxy network systems. These uniquely designed monomers were prepared via both Friedel-Crafts and Grignard techniques. In particular, two arylene …
-
Synthesis and characterization of perfectly alternating segmented copolymers comprised of poly(dimethylsiloxane)s and engineering thermoplastics
… anhydride disiloxane endcapping species. Aromatic amine-terminated engineering thermoplastics were synthesized through either nucleophilic aromatic substitution in the presence of a “monofunctional” aminophenol endcapper (as for poly(arylene ether ketone)s and poly(arylene ether sulfone)) …
-
Insights into the mechanism of action of quinoline antimalarials against Plasmodium falciparum revealed by novel fluorescent analogues and chemical proteomics
… and was attached to the quinoline core by nucleophilic aromatic substitution. The length of the spacer chain between the quinoline and the fluorophore was varied by preparing NBD-labelled amino acids and their corresponding succinimidyl esters. A novel NBD-labelled chloroquine derivative …
-
Exploiting cooperative effects in s-Block organometallics for new applications in synthesis and catalysis
… regioselective magnesiation of heterocyclic and aromatic molecules, including pyrazine or 1,2,4,5-tetrafluorobenzene, can be achieved at room temperature. Structural studies of these metallated intermediates have revealed a crucial stabilising role of the β-diketiminate ligand, which facilitates …
-
Reactive Peptides for Site-Selective Cysteine and Lysine Bioconjugation
… This interface consists of two peptides: a nucleophilic, cysteine-containing peptide and an electrophilic, perfluoroarylated peptide. The unique sequences of these peptides enhance the reaction rate of a nucleophilic aromatic substitution reaction between these two peptides. Potential …
Page 1 of 3