Physical Sciences and Mathematics Commons^™

Synthesis Of Diaryl And Alkyl-Aryl Ethers Via Diaryl Iodonium Reagents, Rory Tennessee Gallagher

Dissertations and Theses

Substituted benzenoid rings are a prevalent motif in many industries including high tech, agrochemicals, and pharmaceuticals. As a result, the arylation of chemical compounds is a highly sought-after chemical transformation. There are many literature methods to achieve this chemical transformation, nucleophilic aromatic substitution and transition metal catalysis are both widely used and studied. Diaryliodonium salt mediated chemistry is an attractive alternative to these methods as it does not require the expensive toxic metals and designer ligands of transition metal catalysis and is not restricted to electron deficient aryl rings with specific substitution patterns like nucleophilic aromatic substitution.

Many diaryliodonium salt …

Speciation Of Diaryliodonium Salts In Solution And Their Reactivity Towards N-Nucleophiles (Phthalimide And Amines) And O-Nucleophiles (Phenols And Phenoxide), Souradeep Basu

Dissertations and Theses

Benzenoid rings are prevalent in pharmaceutical drug molecules, agrochemical molecules and even in some polymers used in electronic device. Aryl rings are often installed using metal catalysis, however, metal free arylations are known but limited. Diaryliodonium salts are novel electrophilic arylating agents. Herein, metal free N-arylation of phthalimide and diarylether formation using aryl(TMP)iodonium salts is described.

The structure of diaryliodonium salts has been primarily studied in either the solid state or in-silico. The structure and speciation of diaryliodonium salts in solution is not well explored. In this work evidence of dimer formation of aryl(Mes)iodonium salts in chloroform using …

The Preparation Of Diaryliodonium Salts For Application In Arylation Chemistry, Thomas Ludwig Seidl

Dissertations and Theses

Diaryliodonium salts offer potential as novel reagents for arylation chemistry. An overall goal and successful outcome of this work has been to further understanding of diaryliodonium salt chemistry by developing practical methods that enable chemists more convenient access to these reagents, for the purpose of reaction development. To this end a robust and convenient preparation method has been developed and resulted in novel commercially available diaryliodonium salts. The remainder of the work described, has focused on understanding the parameters important to diaryliodonium mediated arylation and has resulted in a solid framework that multiple future development efforts can build upon.

A …

The Discovery And Development Of Metal-Free Arylation Reactions With Unsymmetrical Diaryliodonium Salts, Sunil Kumar Sundalam

Dissertations and Theses

Functionalizing arenes and heteroarenes has been an active area of research since the 19th century, due to the presence of these molecular structures in many industrially important sectors. A tremendous amount of research has been published in achieving these chemical transformations using stoichiometric reagents and transition metal-catalyzed reactions. However, challenges still remain. An alternative and comparable methodology to metal-catalyzed reactions to overcome the drawbacks will advance this particular area of research is desirable.

Hypervalent iodine compounds offer a promising approach to metal-free arylation reactions. These mild, air and moisture stable compounds have showed significant success as non-toxic and metal-free reagents …

Synthesis Of Novel Dienes And Cyclic Compounds Via Olefin Metathesis Reactions Catalyzed By The Second Generation Grubbs Catalyst, Patrick Joseph Carey

Honors Theses

Transition metal-catalyzed olefin metathesis reactions play a significant role in chemical synthesis. These reactions are currently applied across several disciplines, and their full potential has not yet been reached. This project details the synthesis of spiro[3-cyclopentene-1,9’-[9H]fluorene], 1-(1-amino-2-methylpropyl)-3-cyclopentenol, and the eugenol dimer via olefin metathesis reactions catalyzed by the second generation Grubbs catalyst. The unique structural properties of each compound help demonstrate the widespread abilities of these reactions. Also reported are the novel three-dimensional crystal structures of both spiro[3-cyclopentene-1,9’-[9H]fluorene] and the eugenol dimer. These structures were determined via X-ray diffraction crystallography methods using a Bruker SMART X2S Single Crystal Diffractometer. Both …

Generation Of Diverse Molecular Complexity From Simple Hydrocarbons, Anobick Sar

Dissertations (1934 -)

In an effort to make diverse molecular complexity from simple hydrocarbons, tricarbonyl(cyclohexadienyl)iron(+1) cation was prepared in two steps from 1, 3-cycloxehadiene. Reactivity of the symmetric iron cation with heteroatom nucleophiles and stabilized carbon nucleophiles was studied. Nucleophilic attack of potassium phthalimide at the dienyl terminus of the cation followed by oxidative decomplexation with Ce4+ provided the ligand N-(2,4-cyclohexadiene-1-yl)phthalimide. A series of stereochemically diverse polyhydroxyl aminocyclohexane "aminocyclitols" derivatives and a number of racemic and optically active hydroxy-and polyhydroxy 1,3-diaminocyclohexane derivatives have been synthesized from N-(2,4-cyclohexadiene-1-yl)phthalimide. The relative stereochemistries of the compounds ware assigned on the basis of the 1H NMR data …

Photochemical Generation Of 2-Methoxy-2methylpropylidene And Its Rearrangement Pathways, Stanislav Presolski

Honors Theses

2-methoxy-2-methylpropylidene was photochemically generated from a non-nitrogenous precursor, 1a,9b-Dihydro-IH-cyclopropa[1]phenanthrene-l-etbane 2-methoxy-2-methyl, available in two steps from phenanthrene. Two competing rearrangement pathways were observed for the p-methoxy carbene, 1,2-methyl shift and C-H insertion, which had varying weights depending on the solvent used. Nevertheless, the C-H insertion was always predominant, contrary to the current understanding of B-substituted carbenes, which apparently needs revision. An attempt was also made to measure by LFP the rate constant of rearrangement and lifetime of the stabilized l-chloro-2-methoxy-2-metbylpropylidene.

Photochemical Generation And Intramolecular Chemistry Of 2-Hydroxy-2-Methylpropylidene, Robin Farlow

Honors Theses

2-(1a,9b-Dihydro-lH-cyclopropa[l]phenanthren-1-yl)-propan-2-ol was synthesized by two different but related synthetic routes and characterized by melting point, IR GC/MS, CHN, and NMR spectroscopy. Photolysis of the alcohol in benzene d-6 led to the formation of 2-butanone, 1-methylcyclopropanol, and 2,2-dimethyloxirane in a 26:10:1 ratio via 2-hydroxy-2methylpropylidene, a novel ?-hydroxycarbene. These products are a consequence of intramolecular insertions of the carbene into C-C, C-H, and O-H bonds. Molecular orbital calculations performed at the Becke-3LYP/6-31G(d) level indicate that the singlet form of this carbene is more thermodynamically stable than the triplet. Furthermore, the transition states to the three products from the singlet species were modeled …

Synthetic Approach To Hexaoxa[6]Peristylanes. A Novel Ddq-Induced Oxidative Rearrangement, Douglas Arthur Otte

Honors Theses

The structural beauty and interesting bonding properties of polycyclic cage compounds have been a source of fascination to many chemists. In this work, progress toward the synthesis of large oxabowl systems, such as hexaoxa[6]peristylane and its derivative dipbenylhexaoxa[6)peristylane, is described. Thus, the adduct obtained from the cycloaddition of maleic anhydride and cyc!ooctatetraene is converted into key dicarbonyl intermediates. Subsequently, the ozonolysis of these intermediates is carried out in order to generate hexaoxa(6)peristylane as well as diphenylhexaoxa[6]peristylane. Molecular modeling studies, performed at the semi-empirical level, are also described.

Synthesis And Characterization Of Novel Fluorine Containing Alkylsulfonyls And Sulfonates : Fluorinated Sulfonyl Methanes And Derivatives, Nelson R. Holcomb

Dissertations and Theses

A series of salts of the strong fluorocarbon acid bis(trifluoromethylsulfonyl)methane were made: (CF3S02 ) 2CHK, (CF3S02 ) 2CHLi, [ (CF3S02 ) 2CH] 2Ca, [ (CF3S02 ) 2CH] 2Hg, (CF3S02 ) 2CHAg, [ (CF3S02 ) 2CH] 3La. Their reactivity and use as organic intermediates were investigated. The salts were made from their corresponding carbonates, oxides, or hydrides. The reaction times for the salts is generally short, however the purification process was laborious, involving recrystallization from organic solvents and drying under vacuum. The lithium salt is being evaluated as a solid state battery electrolyte. Derivatives of bis(trifluoromethylsulfonyl)methane were made by using the …

Substituent Effects On Strained Rings. Part A ; The Kinetics Of Hydrolysis Of A Quinuclidone Using Ftir. Part B, Yeu-Yi Chiu

Theses

PART A: The energies of a series of monosubstitued propane, cyclopropane and cyclopropene compounds were calculated using ab initio molecular orbital calculations optimized at the 3-21G level using Gaussian 82 and Gaussian 86 programs. The effects of substituents on stabilization energies and geometries are rationalized with respect to the parent molecules. The result is presented which indicated that for substituted cyclopropyl and cyclopropenyl compounds, most of the substituents induce stabilization except the —NC substituent group is destabilizing in cyclopropyl and cyclopropenyl systems. Indications of relative electrostatic and resonance effects are also analyzed. A linear free energy relationship has been exam-ined …

The Reaction Of 2-Arylprop-1-En-3-Yltrimethylammonium Iodides With Sulfur Nucleophiles And Useful Synthetic Applications Of These Adducts, Steven J. Duranceau

Retrospective Theses and Dissertations

This report discusses research involving the reactions of 2-arylprop-1-en-3-yltrimethyl ammonium iodides with sulfur nucleophiles and the useful synthetic applications of the adducts formed. The present work may be subdivided into four sections: 1) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with benzenethiol; 2) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with the sodium salt of benzenesulfinic acid; 3) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with 2-mercapto-1-methyl imidazole; and 4) oxidation of 2-aryl-3-phenylthio-1-propenes and 2-aryl-3-phenylsulfonyl-1-propenes using sodium perborate. This report outlines the experimental conditions and procedures responsible for the synthesis of these products; in addition, this report describes the physical properties, NMR and IR spectra of …

New Synthetic Applications Of Enaminoketones, Timothy J. Buck

Retrospective Theses and Dissertations

This report discusses research concerning synthetic applications of enaminoketones. The work may be divided into four parts as follows: a) replacement of the dimethylamino group of certain enaminones by other amine groups through a simple procedure; b) formation of 3-alkyl-pyrazoles; c) formation of 2-amino-4-alkyl-pyrimidines; d) synthesis and subsequent reduction of iminium salts. The starting materials (E-1-(N,N-dimethylamino)-1-alkene-3-ones) have been condensed with hydrazine and guanidine to form pyrazoles and pyrimidines, respectively. The same starting materials have been reacted with POCl₃ in CH₂Cl₂ to produce chlorovinyliminium salts. These have then been reacted in situ with reducing agents to produce …

Synthesis Of Hydroxy Tetronic Acid, Phyllis Elaine Hoar

Senior Scholar Papers

A Historical Introduction is given as background material to the problem of the existance of an ?-hydroxy-?-substituted tetronic acid as the intermediate in the oxidation of tetronic acids to ?-diketones. Three schemes are proposed by which this intermediate may be synthesized, starting with ethyl acetoacetate. In the first scheme the ?-substituted tetronic acid is oxidized by lead tetraacetate to the ?-acetoxy-?-substituted compound. In the second and third schemes, the lead tetraacetate oxidation can be applied to the ?-substituted acetoacetic ester, or the ?-substituted acetoacetic ester can be chlorinated with sulfuric chloride and then converted to the ?-acetoxy ester. Experimental work …