Physical Sciences and Mathematics Commons^™

Intramolecular Friedel-Crafts Addition Of Indoles To Tertiary Allylic Alcohols, Bryan H. Wakefield, Romie Barnes, Traeannah Brown, Ashley M. Jones, Victoria A. Knotts, Christina Martinetti

Journal of the South Carolina Academy of Science

An intermolecular Friedel-Crafts alkylation of indole and tertiary allylic alcohols has been developed. The allylic alcohols were synthesized using a two-step procedure, then exposure of these alcohols to diphenyl phosphate facilitated the desired annulation reaction. This reaction tolerated a variety of indole substitutions to yield 1H,2H,3H,4H-pyrido[1,2-a]indoles.

Study On The Alkylation Of Aromatic Hydrocarbons And Propylene, Wanglai Dong, Wentao Ma, Xinyao Li, Xingbang Hu, Zheng Zhou

Turkish Journal of Chemistry

In order to improve the efficiency of the alkylation reaction to aromatic hydrocarbons and propylene, different types of catalysts were screened, including ultra-stable Y molecular sieves (USY), solid phosphoric acid (SPA), ZSM type molecular sieve (HZSM), etc. The effects of reaction temperature, catalyst loading, and reaction time on the conversion rate of aromatic hydrocarbons and the selectivity of target products were investigated using the high-pressure reaction device. The catalysts were characterized by XRD, BET, SEM, FT-IR, NH3-TPD, and other methods. The experimental results show that the USY catalyst exhibits higher catalytic activity for alkylation. This catalyst can be used for …

Cu-Catalyzed Phenol O-Methylation With Methylboronic Acid, Mairead E. Bartlett, Yingchuan Zhu, Uma Bhagwat Gaffney, Joyce Lee, Miranda Wu, Betemariam Sharew, Angela K. Chavez, David J. Gorin

Chemistry: Faculty Publications

A Cu-catalyzed oxidative cross-coupling of phenols with methylboronic acid to form aryl methyl ethers has been developed, expanding the scope of Chan-Evans-Lam alkylation. Electron-deficient phenol derivatives with a broad array of functional groups are methylated in high yields. Increased reaction temperature and catalyst loading enables the methylation of substrates incorporating pyridine and dihydroquinolone motifs. Electron-rich phenol derivatives are poor substrates for the methylation; the characterization of C−H homodimerization products formed from these substrates illuminates a competing mechanistic pathway.

Not-So-Innocent Anions Determine The Mechanism Of Cationic Alkylators, S. Maryamdokht Taimoory, Vincenzo Alessandro Cataldo, Andreas Schäfer, John F. Trant, Ryan Guterman

Chemistry and Biochemistry Publications

Alkylating reagents based on thioimidazolium ionic liquids were synthesized and the influence of the anion on the alkylation reaction mechanism explored in detail using both experimental and computational methods. Thioimidazolium cations transfer alkyl substituents to nucleophiles, however the reaction rate was highly dependent on anion identity, demonstrating that the anion is not innocent in the mechanism. Detailed analysis of the computationally-derived potential energy surfaces associated with possible mechanisms indicated that this dependence arises from a combination of anion induced electronic, steric and coordinating effects, with highly nucleophilic anions catalyzing a 2-step process while highly non-nucleophilic, delocalized anions favor a 1-step …

C-Metalated Nitriles: Diastereoselective Alkylations And Arylations, Robert John Mycka

Electronic Theses and Dissertations

Development of an sp³ hybridized halogen-magnesium exchange route to Grignard reagents, chelation-controlled asymmetric induction of γ- and δ-hydroxynitriles as well as a diastereoselective arylation procedure for C-zincated nitriles have been explored. Sequential addition of i-PrMgCl and n-BuLi to 3- and 4-carbon iodoalcohols triggers a facile halogen-metal exchange to generate cyclic magnesium alkoxides capable of intercepting electrophiles to produce a diverse range of substituted alcohols. This work advances progress toward the synthesis of highly desirable chiral Grignard reagents.

Double deprotonation of γ- and δ-acyclic hydroxynitriles with i-PrMgCl effects highly diastereoselective alkylations via a singly-chelated magnesiated nitriles. …

An Improved Synthesis Of Adefovir And Related Analogues, Timothy P. O'Sullivan, Et Al

Physical Sciences Publications

An improved synthesis of the antiviral drug adefovir is presented. Problems associated with current routes to adefovir include capricious yields and a reliance on problematic reagents and solvents, such as magnesium tert-butoxide and DMF, to achieve high conversions to the target. A systematic study within our laboratory led to the identification of an iodide reagent which affords higher yields than previous approaches and allows for reactions to be conducted up to 10 g in scale under milder conditions. The use of a novel tetrabutylammonium salt of adenine facilitates alkylations in solvents other than DMF. Additionally, we have investigated how …

Synthesis And Metalation Of Internally Alkylated Porphyrinoids, Alissa Nicole Latham

Theses and Dissertations

The mechanism behind alkyl migration in palladium(II) benzocarbaporphyrins was investigated through the synthesis of a 23-methylcarbaporphyrin. It was found that palladium insertion led to methyl group migration to C21 and it is proposed that this occurs through an oxidative addition onto the palladium metal center, followed by a reductive elimination to transfer the methyl to the internal carbon. A similar rearrangement was observed when 23-methylcarbaporphyrin was reacted with [Rh(CO)2Cl]2 and resulted in the formation of a rhodium(III) complex containing a three-membered rhodacycle. The syntheses of rhodium(I) and rhodium(III) derivatives of other carbaporphyrins, including 21- and 22-methylbenzo-carbaporphyrins, were probed and four …

Dft-Assisted Design And Evaluation Of Bifunctional Amine/Pyridine-Oxazoline Metal Catalysts For Additions Of Ketones To Unactivated Alkenes And Alkynes, Eric Greve, Jacob D. Porter, Chris Dockendorff

Chemistry Faculty Research and Publications

Bifunctional catalyst systems for the direct addition of ­ketones to unactivated alkenes/alkynes were designed and modeled by density functional theory (DFT). The designed catalysts possess bidentate ligands suitable for binding of pi-acidic group 10 metals capable of activating alkenes/alkynes, and a tethered organocatalyst amine to ­activate the ketone via formation of a nucleophilic enamine intermediate. The structures of the designed catalysts before and after C–C bond formation were optimized using DFT, and reaction steps involving group 10 metals were predicted to be significantly exergonic. A novel oxazoline precatalyst with a tethered amine separated by a meta-substituted benzene spacer was synthesized …

One-Pot Enol Silane Formation-Alkylation Of Ketones With Propargyl Carboxylates Promoted By Trimethylsilyl Trifluoromethanesulfonate, C. Wade Downey, Danielle N. Confair, Yiqi Liu, Elizabeth D. Heafner

Chemistry Faculty Publications

Ketones readily undergo conversion to enol silanes in the presence of trialkylamine base and trimethylsilyl trifluoromethanesulfonate (TMSOTf) and add to propargyl cations to yield b-alkynyl ketones. The propargyl cations are generated in the same reaction flask through the TMSOTf-promoted ionization of propargyl acetates or propargyl propionates. A range of enol silane precursors and propargyl carboxylates reacts efficiently (20 examples, up to 99% yield). Cyclization of a representative product in the presence of TMSOTf provided 61% yield of the trisubstituted furan.

Decarbonylative Cross Coupling Of Phthalimides With Diorganozinc Reagents—Efforts Toward Catalysis, Kimberly S. Deglopper, Sarah K. Fodor, Thomas Bd Endean, Jeffrey B. Johnson

Faculty Publications

The decarbonylative coupling of phthalimides with diorganozinc reagents to form o-substituted benzamides has been previously demonstrated as a viable process, but only with stoichiometric nickel(0). Investigations into a number of reaction variables, including solvent, ligand, and substrate substitution, have yielded multiple sets of conditions capable of achieving up to 10 catalyst turnovers, most successfully with the use of electron withdrawing nitrogen substituents on the phthalimide. In addition, these investigations have provided insight into the intermediates within the catalytic cycle and have revealed new approaches to the development of a general catalytic methodology.

Reactivity Of (3-Methylpentadienyl)Iron(1+) Cation: Late-Stage Introduction Of A (3-Methyl-2z,4-Pentadien-1-Yl) Side Chain, Subhabrata Chaudhury, Shukun Li, William A. Donaldson

Chemistry Faculty Research and Publications

The 3-methyl-2Z,4-pentadien-1-yl sidechain is found in various sesquiterpenes and diterpenes. A route for the late stage introduction of this functionality was developed which relies on nucleophilic attack on the (3-methylpentadienyl)iron(1+) cation, followed by oxidative decomplexation. This methodology was applied to the synthesis of the proposed structure of heteroscyphic acid A methyl ester. Realization of this synthesis led to a correction of the proposed structure.

Synthesis Of Diazonium Perfluoroalkyl(Aryl) Sufonimide (Pfsi) Zwitterions For Solid Acid Alkylation Catalysts, Husan Ahmad

Undergraduate Honors Theses

The final objective of this project is to create an environmentally friendly solid alkylation catalyst to replace the commercially available liquid acid catalysts, such as hydrofluoric acid and sulfuric acid, which are used in the petroleum industry. My research target is to synthesize the diazonium PFSI zwitterions, which can be chemically grafted on the silica as the solid alkylation catalyst. A 4-steps synthesis is designed to prepare the diazonium PFSI zwitterions. The first two steps were successfully completed in the lab. The first one is to prepare the starting material of 4-nitrobenzenesulfonamide from an ammonolysis reaction between 4-nitrobenzene sulfonyl chloride …

Silyl Trifluoromethanesulfonate-Activated Para-Methoxybenzyl Methyl Ether As An Alkylating Agent For Thiols And Aryl Ketones, C. Wade Downey, Sarah E. Covington, Derek C. Obenschain, Evan Halliday, James T. Rague, Danielle N. Confair

Chemistry Faculty Publications

para-Methoxybenzyl methyl ether acts as an alkylating agent for thiols in the presence of trimethylsilyl trifluoromethanesulfonate and trialkylamine base in good yields (58-96%). Aryl ketones are alkylated under similar conditions, probably through an enol silane intermediate, also in high yields (67-95%). The active alkylating species is likely a p-methoxybenzyl cation.

Efficient One-Pot Alkylation Of Imines Using Nanosilver Iodide In Aqueous Media, Javad Safaei Ghomi, Ahmad Kakavand-Qalenoei, Mohammad Ali Ghasemzadeh, Masoud Salavati-Niasari

Turkish Journal of Chemistry

An efficient ecofriendly method for the alkylation reaction of various imines is described by a simple one-pot reaction of aldehydes, amines and alkyl iodides in the presence of AgI nanoparticles in aqueous media. Silver iodide nanoparticles mediated an enhanced rate and facility of reaction and showed high influence in the green synthesis of some amine derivatives. Moreover, this nanoparticle increased the yields of products and decreased the reaction times in all cases. The heterogeneous mediator was fully characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and FT-IR experimental techniques.

Synthesis Of Tetrahydroisoquinocarbazoles Via C-2 Alkylation Of Indoles With 2-Alkoxycyclopropanoate Esters., Barbora Bajtos, Brian L Pagenkopf

Chemistry Publications

A concise method for the synthesis of several tetrahydroisoquinocarbazole derivatives is reported, where the core is prepared in six steps from tryptophol in 51% overall yield. The pentacyclic analogs are constructed via a dipolar C-2 alkylation of a 3-substituted indole with a 2-alkoxycyclopropanoate ester and a SmBr(2)-HMPA mediated ketyl-alkene ring closure.

C-2/C-3 Annulation And C-2 Alkylation Of Indoles With 2-Alkoxycyclopropanoate Esters., Barbora Bajtos, Ming Yu, Hongda Zhao, Brian L Pagenkopf

Chemistry Publications

The annulation reaction between various indoles and 2-alkoxycyclopropanoate esters is reported. Both high efficiency and complete stereochemical control were observed in some cases with this annulation process. A single stereocenter on the cyclopropane controls the diastereoselective formation of up to four new stereocenters. A different reaction course was observed with 3-substituted indole substrates, and an intervening C-3 to C-2-migration process arose that gives synthetically useful C-2 alkylation indole products.

Initial Studies On A Novel Target-Promoted Dna Alkylation System, Ting Xu

Theses and Dissertations

A novel target-promoted DNA alkylation system was designed, which consists of a DNA intercalating/alkylating quinone methide (QM) precursor, a removable amine linker, and a sequence-specific delivery. The QM in this system was regenerated by eliminating the amino linker promoted by the hydrophobic interaction between the target DNA and the intercalating QM precursor. Three alkylation model systems (methoxyl polycyclic system, intramolecular hydrogen bonding system and biaryl system) were proposed and synthesized. The potential DNA QM alkylation was investigated by deoxyadenosine (dA) and deoxyguanosine (dG) alkylation with the biaryl system. Only one deoxynucleoside adduct was observed when dA or dG reacted with …

N9 Alkylation And Glycosylation Of Purines; A Practical Synthesis Of 2-Chloro-2'-Deoxyadenosine, Minghong Zhong

Theses and Dissertations

(a) The Robins reagent [2-acetamido-6-O-(diphenylcarbamoyl)purine] was utilized for glycosylation under Lewis acid conditions. Regioselectivity of glycosylation depends on the glycosyl donor and its 2-O- or 2-N-protecting group. Regioselective N9 glycosylation of 2-acetamido-6-O-(diphenylcarbamoyl)purine with problematic glucosamine has been accomplished by protecting the amino function as a phthalimido group with consequent stabilization of the oxocarbenium cation, and lowering the activation energy by introduction of trichloroacetimidate at the anomeric carbon.

(b) 6-Heteroaryl functions [6-(1,2,4-triazol-4-yl) and 6-(imidazol-1-yl)] were introduced into purine derivatives for regioselective N9 alkylation. The regiospecificity of alkylation mainly results from steric effects due to the coplanar conformation of the two linked …

Synthesis And Antitumor Activities Of Some New 4-(1-Naphthylidenamino)- And 4-(1-Naphthylmethylamino)-1,2,4-Triazol-5-One Derivatives, Nesli̇han Demi̇rbaş, Reyhan Uğurluoğlu

Turkish Journal of Chemistry

A series of 4-(1-naphthylidenamino)-1,2,4-triazol-5-one derivatives (3a-e) were synthesized by condensation of corresponding 3-alkyl-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones with 1-naphthaldehyde. Acetylation and alkylation of these compounds gave 4a-e and 5a-e, respectively. Sodium borohydride reduction of 1-naphthylidenamino derivatives afforded naphthylmethylamino derivatives, which were subsequently acetylated. Depending on the duration of the acetylation, mono or bis acetamide derivatives were obtained. The in vitro antitumor activities of some selected compounds were screened and compounds 3e, 5c, 6e and 9c} were found to be active.

Aromatic Acetals : Their Synthesis And Alkylation, Robert Conner Gass

University of the Pacific Theses and Dissertations

The purpose of this investigation was to study the known methods of forming acetals and find one or several that could be used in further investigation. In connection with the reactions, the use of various catalysts was pertinent. Some of the catalysts used were hydrogen chloride, calcium chloride, ferric chloride, aromatic sulfonic acids, and other. There was no data available comparing the sulfonic acids with the inorganic salts and mineral acids. For that reason one of the subsidiary problems of this investigation was such a comparison.

In order to investigate stability, several acetals were subjected to conditions intended to produce …