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Synthetic Studies Toward Pyrrolizidine and Indolizidine Carbon SkeletonChia, Wei-Ju 17 June 2002 (has links)
none
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Radical and palladium mediated cyclisations for the synthesis of heterocyclic ring systemsKofie, William January 2003 (has links)
No description available.
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The mechanisms of reactions of #beta#-sultamsBaxter, Nicholas James January 1998 (has links)
No description available.
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Catalytic hydrogenation of an aromatic sulfonyl chloride into thiophenolRouckout, Nicolas Julien 15 May 2009 (has links)
The catalytic hydrogenation of an aromatic sulfonyl chloride was investigated in
continuous and semi-batch mode processes using a Robinson-Mahoney stationary basket
reactor. A complete experimental unit was designed and built. The operating and
analytical procedures have been developed and the methodologies to gather the kinetic
data have been described. Hydrogenation reactions were conducted at a reaction pressure
of 364.7 psia, at three different reaction temperatures: 85 °C, 97 °C and 110 °C, at five
different residence times: 0.6 (only at 110 °C), 1.0, 1.5, 2.0, 3.1 hr, with the hydrogen to
the aromatic sulfonyl chloride molar ratio: 8.0 mol/mol and hydrogen to argon molar
ratio: 3.0 mol/mol. Intrinsic reaction rates of the reacting species were obtained on the
surface of a commercial 1 wt% palladium on charcoal catalyst.
The conversion and molar yield profiles of the reacting species with respect to
process time suggest a deactivation of the 1 wt % palladium on charcoal catalyst. Kinetic
data collected in a continuous process mode show that the catalyst is deactivated during
an experiment when the process time equal to two to three times the residence time of
the liquid within the reactor. XRD analysis shows that the active sites are blocked and an
amorphous layer was formed on the surface of the palladium catalyst. Semi-Batch mode
experimental data were obtained at 110 °C after 8 hours of reaction time for several
aromatic sulfonyl chlorides. A kinetic model has been developed, which includes adsorption of individual
components and surface reactions as well as rate equations of the Hougen-Watson type.
A hyperbolic deactivation function expressed in term of process time is implemented in
the Hougen-Watson equation rates. The mathematical model consists of non-linear and
simultaneous differential equations with multiple variables. The kinetic parameters were
estimated from the minimization of a multi-response objective function by means of a
sequential quadratic program, which includes a quasi-Newton algorithm. The statistical
analysis was based on the t- and F-tests and the simulated results were compared to the
experimental data.
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The epoxy Ramberg Bäcklund rearrangement (ERBR) and related studiesEvans, Paul January 1998 (has links)
No description available.
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Synthetic Studies Toward Tetracyclic and Pentacyclic Indole AlkaloidsChen, Tzong-Yi 25 July 2000 (has links)
none
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The study of chloride exchange reactions in some aromatic carbonyl and sulphonyl chloride in t-Amyl alcohol.Wan, Yat-shing, Raymond. January 1972 (has links)
Thesis--M. Phil., University of Hong Kong. / Typescript.
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Reactions of sulfonyl carbanions with succinic acid derivatives a simple two-step synthesis of sym-1,4-diketones and an attempted synthesis of r-alkylidene-r-butyrolactones /Dusanee Vanichpitmonanan, Manat Pohmakotr, January 1982 (has links) (PDF)
Thesis (M.Sc. (Organic Chemistry))--Mahidol University, 1982.
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Methodology to Access Sulfonyl FluoridesRockwell James Pokrant (16556754) 17 July 2023 (has links)
<p>In recent years, sulfonyl fluorides have garnered significant attention in the synthetic organic and biochemical communities. Sulfonyl fluorides exhibit unique reactivity, as nucleophilic addition to the sulfur atom and subsequent elimination of fluoride only occurs under specific reaction conditions (otherwise known as SuFEx). Due to their inherent stability, sulfonyl fluorides are commonly used as biochemical probes to elucidate the structure of proteins. Sulfonyl fluorides also hold promise as irreversible covalent inhibitors. Despite the many potential applications of sulfonyl fluorides, methods to access this functional group remain underdeveloped, often requiring complex starting materials, or the use of hazardous reagents.</p>
<p>Electrochemistry offers an attractive alternative to standard preparations of sulfonyl fluorides. Chapter 1 provides an overview of modern methods employed to synthesize sulfonyl fluorides, as well as key developments in synthetic organic electrochemistry. Chapter 1 closes with how the standardization of electrochemical reactions has allowed synthetic organic chemists to accurately reproduce electrochemical transformations.</p>
<p>In Chapter 2, we developed an electrochemical method to access sulfonyl fluorides. The developed method operates by subjecting sulfones to electrochemical conditions, which initiates fragmentation of C–S bonds, and subsequent fluorination of a radical intermediate to realize the sulfonyl fluoride functional group. Early optimization focused on the synthesis of an optimal leaving group to bias the system towards formation of the desired sulfonyl fluoride in the presence of AgF<sub>2</sub>. Once a leaving group was established, Lewis acids were screened in an attempt to activate the sulfone for substitution. Lewis acidic additives were later determined to serve as sacrificial oxidants as they did not chelate the sulfone starting materials. Reactions were run in divided and undivided electrochemical cells depending on the fluorinating reagent. Reactions with AgF<sub>2</sub> were run in an undivided electrochemical cell to prevent cathodic plating of Ag<sup>0</sup>. However, comparable results were achieved in an undivided electrochemical cell if AgF<sub>2</sub> was replaced with Selectfluor. Investigation into the incorporation of the leaving group into other substrates is ongoing. We hope to further develop this methodology to access complex sulfonyl fluorides and encourage the development of electrochemical methods in synthetic organic chemistry.</p>
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Sulfonyl Chlorides as Versatile Reagents for Chelate-assisted C–H Bond FunctionalizationsDimitrijevic, Elena 14 January 2010 (has links)
Despite the great abundance of C–H bonds in readily available starting materials, their use in synthesis of functionalized molecules has been hampered by the high bond strengths, rendering them inert to common organic reagents. However, recent progress in the field has addressed this issue, enabling selective C–H bond functionalizations to be performed using catalytic transition metal mediated processes.
Herein, the use of sulfonyl chlorides as versatile reagents for C–H bond functionalizations is reported. Using chelation assistance, the regioselective conversion of C–H bonds to either C–S, C–Cl or C–C bonds was achieved. The methodology development, substrate scope determination and mechanistic investigations will be discussed.
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