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Studies Towards Synthesis of Paraconic Acids
Title
Studies Towards Synthesis of Paraconic Acids.
Creator
Soto, Karenia, Dragojlovic, Veljko
Abstract/Description
FAU's Office of Undergraduate Research and Inquiry hosts an annual symposium where students engaged in undergraduate research may present their findings either through a poster presentation or an oral presentation.
Date Issued
2011
PURL
http://purl.flvc.org/fau/fd/FA00005450
Format
Document (PDF)
Halosulfites as a leaving groups in organic synthesis
Title
Halosulfites as a leaving groups in organic synthesis.
Creator
Kissner, William, Dragojlovic, Veljko
Date Issued
2013-04-05
PURL
http://purl.flvc.org/fcla/dt/3361103
Subject Headings
Organic compounds--Synthesis, Substitution reactions
Format
Document (PDF)
Chlorosulfite as a Leaving Group in Organic Synthesis
Title
Chlorosulfite as a Leaving Group in Organic Synthesis.
Creator
Kissner, William, Dragojlovic, Veljko
Date Issued
2012-04-06
PURL
http://purl.flvc.org/fau/fd/FA00005473
Format
Document (PDF)
Phase-vanishing halolactonization of neat substrates
Title
Phase-vanishing halolactonization of neat substrates.
Creator
Windmon, Nicole, Dragojlovic, Veljko
Date Issued
2008-08-11
PURL
http://purl.flvc.org/fau/fd/FAUIR000134
Format
Citation
Solvent-free phase-vanishing reactions with PTFE (Teflon®) as a phase screen
Title
Solvent-free phase-vanishing reactions with PTFE (Teflon®) as a phase screen.
Creator
Pels, Kevin C, Dragojlovic, Veljko
Date Issued
2009-12-09
PURL
http://purl.flvc.org/fau/fd/FAUIR000135
Format
Citation
Abamectin: ant toxin or antifeedant?
Title
Abamectin: ant toxin or antifeedant?.
Creator
Kissner, William, Kaul, Christopher, McGuire, Megan, Pick, David, Dragojlovic, Veljko
Date Issued
2012-04-06
PURL
http://purl.flvc.org/fcla/dt/3348829
Subject Headings
Abamectin, Toxin, Antifeedant, Chemistry techniques, Pest control
Format
Document (PDF)
Recent Developments in Vapor Phase Phase-Vanishing PTFE Reactions
Title
Recent Developments in Vapor Phase Phase-Vanishing PTFE Reactions.
Creator
Pels, Kevin, Smith, Olivia Lin, Abney, Ancil J., Dragojlovic, Veljko
Abstract/Description
FAU's Office of Undergraduate Research and Inquiry hosts an annual symposium where students engaged in undergraduate research may present their findings either through a poster presentation or an oral presentation.
Date Issued
2011
PURL
http://purl.flvc.org/fau/fd/FA00005445
Format
Document (PDF)
Properties of PTFE tape as a semipermeable membrane in fluorous reactions
Title
Properties of PTFE tape as a semipermeable membrane in fluorous reactions.
Creator
Parsons, Brendon A., Smith, Olivia Lin, Chae, Myeong, Dragojlovic, Veljko
Date Issued
2015-06-09
PURL
http://purl.flvc.org/fau/fd/FAUIR000136
Format
Citation
SynGAP1 Haploinsufficiency affects neuronal structure and development in mouse models
Title
SynGAP1 Haploinsufficiency affects neuronal structure and development in mouse models.
Creator
McGuire, Megan, Dragojlovic, Veljko, Harriet L. Wilkes Honors College
Abstract/Description
Intellectual Disability (ID) is an increasingly common neurological disorder that causes intellectual deficients in cognition and behavior and is scientifically diagnosed by an intelligence score (IQ) under 70 along with the presence of two or more associated behaviors. A recent study showed that sporadic ID in humans was correlated with autosomal dominant de novo mutations in SynGap1.
Date Issued
2013
PURL
http://purl.flvc.org/fau/fd/FA00003525
Format
Document (PDF)
Bio-active organic compounds in the venom of an Endemic Jamaican Ant, Crematogaster vicina
Title
Bio-active organic compounds in the venom of an Endemic Jamaican Ant, Crematogaster vicina.
Creator
Burnett, Brian M, Wetterer, James K., Dragojlovic, Veljko, Harriet L. Wilkes Honors College
Abstract/Description
Bioprospecting, the search for useful compounds found in nature, has led to the discovery of novel drugs and pharmaceuticals. For my thesis research, I analyzed the organic compounds in the venom of Crematogaster vicina Andre, an endemic Jamaican ant. Prior chemical analysis of Crematogaster species revealed diverse, bio-active organic compounds, which included long chained conjugated dienones, furanocembranoid, and diterpenes. I postulated that these types of compounds are characteristic of...
Show moreBioprospecting, the search for useful compounds found in nature, has led to the discovery of novel drugs and pharmaceuticals. For my thesis research, I analyzed the organic compounds in the venom of Crematogaster vicina Andre, an endemic Jamaican ant. Prior chemical analysis of Crematogaster species revealed diverse, bio-active organic compounds, which included long chained conjugated dienones, furanocembranoid, and diterpenes. I postulated that these types of compounds are characteristic of the Crematogaster venom. I used Gas Chromatography- Mass Spectrometry (GC-MS), Sci-Finder database and SDBS database to test my hypothesis with C.vicina venom. I identified one bio-active organic compound of high abundance and similar characteristics of the organic compounds found in venom of the Crematogaster species from Europe: 1, 2 –Dihydro-4-ethylamino-1-methylpyrimidin-2-one, which I isolated as di (phosphate methyl ester).
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Date Issued
2013
PURL
http://purl.flvc.org/fau/fd/FA00003508
Format
Document (PDF)
DIELS-ALDER REACTIONS OF IN SITU GENERA TED CYCLOPENTADIENE IN HYDROCARBON AND FLUOROUS SOL VENTS
Title
DIELS-ALDER REACTIONS OF IN SITU GENERA TED CYCLOPENTADIENE IN HYDROCARBON AND FLUOROUS SOL VENTS.
Creator
Dombrowski, Thomas, Dragojlovic, Veljko, Smith, Eugene, Harriet L. Wilkes Honors College
Abstract/Description
The stereoselectivity ofthe Diels-Alder reaction of cyclopentadiene and maleic anhydride towards its exo adduct was improved in perfluorinated solvents, in comparison to a reaction carried out in hydrocarbon solvents and a solvent free reaction. When using FC-70, the reaction of in situ generated cyclopentadiene and maleic anhydride produced exo- norbomene-cis-5,6-dicarboxylic anhydride and endo- norbomene-cis-5,6- dicarboxylic anhydride in a ratio of 52:32 according to GC-MS analysis. In...
Show moreThe stereoselectivity ofthe Diels-Alder reaction of cyclopentadiene and maleic anhydride towards its exo adduct was improved in perfluorinated solvents, in comparison to a reaction carried out in hydrocarbon solvents and a solvent free reaction. When using FC-70, the reaction of in situ generated cyclopentadiene and maleic anhydride produced exo- norbomene-cis-5,6-dicarboxylic anhydride and endo- norbomene-cis-5,6- dicarboxylic anhydride in a ratio of 52:32 according to GC-MS analysis. In hydrocarbon solvent, mesitylene, the ratio of exo/endo was found to be 23:52, indicating a more kinetically-controlled reaction. Separation of the reaction products by radial chromatography provided the endo adduct in 89% purity and the exo adduct in 47% purity.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00003613
Format
Document (PDF)
HANDLING OF AIR-SENSITIVE REAGENTS IN AN UNDERGRADUATE LABORATORY
Title
HANDLING OF AIR-SENSITIVE REAGENTS IN AN UNDERGRADUATE LABORATORY.
Creator
von Nehring, Erich Scott, Dragojlovic, Veljko, Florida Atlantic University, Harriet L. Wilkes Honors College
Abstract/Description
Chemistry lab work often mandates working with hazardous materials and this existing danger can be easily compounded by inexperience. Undergraduate and bachelors lab workers may be unfamiliar with aspects of lab safety and why certain safety recommendations are in place and the dangers involved. This work outlines safety practices that can be applied when working with air sensitive compounds and some of options that can affect safety procedures such as the type and material a syringe is made of.
Date Issued
2017
PURL
http://purl.flvc.org/fau/fd/FA00012645
Format
Document (PDF)
Recent developments in phase-vanishing reactions with PTFE (Teflon®) as a phase screen
Title
Recent developments in phase-vanishing reactions with PTFE (Teflon®) as a phase screen.
Creator
Pels, Kevin, Dragojlovic, Veljko, Harriet L. Wilkes Honors College, Florida Atlantic University
Abstract/Description
The Phase-Vanishing polytetrafluoroethylene (PTFE, Teflon®) method separates two reactants with a layer of semipermeable polytetrafluoroethylene (PTFE, Teflon®) tape. Expanding on previous work by Van Zee and Dragojlovic, this work investigates the use of the PV-PTFE method under solvent-free conditions and explores its value as a synthetic method for Wittig reactions to produce allenes and allenyl esters. We conducted multiple brominations, halolactonizations, and tandem Diels-Alder...
Show moreThe Phase-Vanishing polytetrafluoroethylene (PTFE, Teflon®) method separates two reactants with a layer of semipermeable polytetrafluoroethylene (PTFE, Teflon®) tape. Expanding on previous work by Van Zee and Dragojlovic, this work investigates the use of the PV-PTFE method under solvent-free conditions and explores its value as a synthetic method for Wittig reactions to produce allenes and allenyl esters. We conducted multiple brominations, halolactonizations, and tandem Diels-Alder-halolactonizations under solvent-free conditions with largely successful results. We also synthesized an allenyl ester, as well as cis-stilbenes using benzyltriphenylphosphonium salts, but cannot report any significant advantage of the PV-PTFE method over known methods.
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Date Issued
2011
PURL
http://purl.flvc.org/fau/fd/FA00003598
Format
Document (PDF)
PTFE tape as a phase screen in the synthesis of chiral α-halo ethers and acetals
Title
PTFE tape as a phase screen in the synthesis of chiral α-halo ethers and acetals.
Creator
Crusco, Salvatore, Dragojlovic, Veljko, Harriet L. Wilkes Honors College, Florida Atlantic University
Abstract/Description
In organic synthesis, the phase-vanishing (PV) technique uses an organofluoride solution to keep two reactive solutions in separate layers, while allowing a reaction to proceed at the interface of the fluorous layer. PV reactions allow otherwise vigorous reactions to proceed at a slower, more controlled rate. In this research, we evaluated the use of PTFE tape as a phase screen in the synthesis of chiral α-halo ethers and acetals. We were successful in synthesizing the two compounds of...
Show moreIn organic synthesis, the phase-vanishing (PV) technique uses an organofluoride solution to keep two reactive solutions in separate layers, while allowing a reaction to proceed at the interface of the fluorous layer. PV reactions allow otherwise vigorous reactions to proceed at a slower, more controlled rate. In this research, we evaluated the use of PTFE tape as a phase screen in the synthesis of chiral α-halo ethers and acetals. We were successful in synthesizing the two compounds of interest, and also successful in their isolation through the use of column chromatography. Since α-halo ethers are known to be carcinogenic, the use of PTFE tape minimizes exposure to the potentially harmful substance.
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Date Issued
2011
PURL
http://purl.flvc.org/fau/fd/FA00003572
Format
Document (PDF)
Studies towards synthesis of paraconic acids
Title
Studies towards synthesis of paraconic acids.
Creator
Soto, Karenia, Dragojlovic, Veljko, Harriet L. Wilkes Honors College, Florida Atlantic University
Abstract/Description
Paraconic acids are naturally occurring compounds synthesized by bacteria and fungi. They are known for having antitumor and antibiotic properties. By use of a phasevanishing (PV) halolactonization with PTFE (Teflon) as a phase screen, we were able to synthesize precursors to these compounds. The PV-PTFE halolactonization of alkenoic acids with iodine monochloride gave the corresponding iodolactones, while halolactonization with bromine gave the corresponding bromolactone. Halolactonization...
Show moreParaconic acids are naturally occurring compounds synthesized by bacteria and fungi. They are known for having antitumor and antibiotic properties. By use of a phasevanishing (PV) halolactonization with PTFE (Teflon) as a phase screen, we were able to synthesize precursors to these compounds. The PV-PTFE halolactonization of alkenoic acids with iodine monochloride gave the corresponding iodolactones, while halolactonization with bromine gave the corresponding bromolactone. Halolactonization of 4-pentenoic acid with water as a solvent also gave good results. Future experiments will explore the synthesis of further precursors by means of a photolytic carbonylation of iodolactone and a phenylation-ruthenium tetroxide oxidation sequence.
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Date Issued
2011
PURL
http://purl.flvc.org/fau/fd/FA00003607
Format
Document (PDF)
CATALYTIC RUTHENIUM TETROXIDE OXIDATION OF ALKENES UNDER ANHYDROUS CONDITIONS
Title
CATALYTIC RUTHENIUM TETROXIDE OXIDATION OF ALKENES UNDER ANHYDROUS CONDITIONS.
Creator
Ansley, Harrison, Dragojlovic, Veljko, Florida Atlantic University, Harriet L. Wilkes Honors College
Abstract/Description
Oxidative cleavage of alkenes was carried out with catalytic ruthenium tetroxide in anhydrous t-butyl alcohol at room temperature. Mild conditions caused a slower and less exhaustive oxidation of the double bond so that aldehydes were the major reaction products.
Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00013637
Format
Document (PDF)
Optimization of Diels-Alder Reactions in Fluorous and Non-fluorous Solvents
Title
Optimization of Diels-Alder Reactions in Fluorous and Non-fluorous Solvents.
Creator
Richmond, Michael, Dragojlovic, Veljko, Florida Atlantic University, Harriet L. Wilkes Honors College
Abstract/Description
The use of fluorous solvents in Diels-Alder reactions have been identified as a viable means to optimize the reaction’s stereoselectivity. Past research on the use of fluorous solvents in Diels-Alder reactions suggest that the characteristics of fluorous solvents (including their tendency to be both liphophobic and hydrophobic) may provide optimal conditions for Diels-Alder reactions. This study investigates these characteristics by comparing the effects of these solvents and other solvents ...
Show moreThe use of fluorous solvents in Diels-Alder reactions have been identified as a viable means to optimize the reaction’s stereoselectivity. Past research on the use of fluorous solvents in Diels-Alder reactions suggest that the characteristics of fluorous solvents (including their tendency to be both liphophobic and hydrophobic) may provide optimal conditions for Diels-Alder reactions. This study investigates these characteristics by comparing the effects of these solvents and other solvents (or the lack thereof) on the Diels-Alder reaction. The use of the fluorous solvent FC-70 was also studied for the purpose of cracking dicyclopentadiene. Literature on molecular interactions and on Diels Alder reactions is utilized to explain how the structural and chemical features of fluorous solvents influence reaction efficiency and selectivity, and how reaction conditions (heat and duration of reaction) alter the efficiency and selectivity. We use structural and thermodynamic arguments to explain these alterations. By better understanding how fluorous solvents function in Diels-Alder reactions, reaction conditions may be improved and their use expanded.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00013643
Format
Document (PDF)
Synthesis of Flosal
Title
Synthesis of Flosal.
Creator
Brettler, Steven, Dragojlovic, Veljko, Florida Atlantic University, Harriet L. Wilkes Honors College
Abstract/Description
Flosal (Jasmonal, Jasmine Aldehyde, (E)-2-benzylideneheptanal) is an important commercial fragrance compound. The principal method for its preparation involves a crossed aldol condensation reaction of heptanal and benzaldehyde. The method has a serious drawback as the synthesis of jasmine aldehyde is accompanied by self-condensation of heptanal to produce foul-smelling 2-pentyl-2-nonenal. We optimized the reaction conditions to maximize yield of jasmine aldehyde while preventing formation of...
Show moreFlosal (Jasmonal, Jasmine Aldehyde, (E)-2-benzylideneheptanal) is an important commercial fragrance compound. The principal method for its preparation involves a crossed aldol condensation reaction of heptanal and benzaldehyde. The method has a serious drawback as the synthesis of jasmine aldehyde is accompanied by self-condensation of heptanal to produce foul-smelling 2-pentyl-2-nonenal. We optimized the reaction conditions to maximize yield of jasmine aldehyde while preventing formation of 2-pentyl-2-nonenal. The desired product was obtained in ~60% yield, with a room for future improvement.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00013638
Format
Document (PDF)