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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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Thesis--M. Phil., University of Hong Kong. / Typescript.

Thesis (M.Sc. (Organic Chemistry))--Mahidol University, 1982.

<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 AgF₂. 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 AgF₂ were run in an undivided electrochemical cell to prevent cathodic plating of Ag⁰. However, comparable results were achieved in an undivided electrochemical cell if AgF₂ 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>

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.