Developing Synergistic Undergraduate Chemistry Labs for Enhanced Student Learning and Integrated...
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Developing Synergistic Undergraduate Chemistry Labs for Enhanced Student Learning and Integrated Research Output Ben Fischer, David Lau, Jennifer Huynh, Christopher Major , Burhan Hussein and Bryan Koivisto* Department of Chemistry and Biology , Ryerson University, 350 Victoria Street, Toronto ON, Canada, M5B 2K3 Chemistry and Biology Department - Second Annual Research Symposium – Wednesday, August 14 th , 2013 Introduction Most traditional undergraduate laboratories focus on reactions to develop basic laboratory techniques using well studied organic reactions; the products of these reactions are seldom studied further. As a result, important structure-property relationships are omitted from practical undergraduate curricula, and products from these labs do not have inherent value outside of technical training. Owing to the expense of basic research, the development of modern synthetic chemistry laboratories, that develop important precursors and building blocks, represents a synergistic opportunity for research and undergraduate education. Methods: Exposure to Modern Synthetic and Characterization Techniques This poster describes the development of a new senior undergraduate synthetic laboratory that focuses on the development and study of novel BODIPY compounds. In addition to traditional organic reactions, a myriad of modern synthetic approaches including microwave syntheses, “click” reactions, and Pd-catalyzed cross-couplings are utilized. Furthermore important structure-property relationships are elucidated using physicochemical characterization (UV-Vis, electrochemical properties, theoretical calculations, the appropriate use of Chemdraw, etc.). The following poster presents the first iteration of a newly developed lab where volunteer summer undergraduates focused on the synthesis of 2,6-disubstituted BODIPY analogues (5 derivatives in total). See Ellie Arnold’s & Burhan Hussein’s poster For more details on how These precursors can be modified Post Modification and Synthetic Possibilities for Research and Dye Libraries Characterization: 1 H NMR Characterization of Optical Properties using UV-Vis and Density Functional Theory (DFT) Characterization by Electrochemical Methods: Cyclic Voltammetry In the Koivisto group at Ryerson University, BODIPY (4,4’-difluoro-4-bora-3a,4a-diaza-s-indacene)-based dyes have garnered considerable attention owing to their highly desirable properties, such as, strong absorption, fluorescence quantum yields, good chemical and photo-stability, and as such have found application in next- generation photovoltaics as non-innocent p-spacers (see above). BODIPYs are synthetically versatile and can be readily tuned using a variety of synthetic techniques. In fact, owing to their non-polar and neutral nature, and their insensitivity to pH and solvent polarity, BODIPY dyes have become ubiquitous for bio-imaging and ion- sensing. BODIPY fluorophores have spectral characteristics that are often superior to those of fluorescein, tetramethylrhodamine, Texas Red and longer-wavelength dyes, but are very expensive probes for research laboratories. data collected in CH 2 Cl 2 using 0.1 M [nBu 4 N] [PF 6 ] at 100 mV/s and referenced to a [Fc]/[Fc] + internal standard (+ 765 mV vs. NHE in CH 2 Cl 2 ) Summary: The Pedagogy of Structure-Property Relationships Acknowledgments A huge thank you to Omar Abdi and Burhan Hussein who were wonderful mentors in the lab and taught us many wonderful techniques. Also a big thank-you goes out to Dr. Koivisto for his guidance and the opportunity to learn in a modern research environment. Finally we would like to thank the Department of Chemistry and Biology for financial assistance in developing this integrated and novel laboratory. After synthesizing a series of molecules with similar structures, students are then asked to tabulate and examine the effects of functional group modification on the BODIPY core and how it effects the redox and optical properties. Consistent with the the de- shielding observed in the 1 H-NMR spectra, both iodides and aldehydes act as electron withdrawing groups; this is also consistent with what is taught in CHY142 and CHY242. In the case of the aldehyde group, the HOMO orbital is stabilized more than the LUMO resulting in a blue-shifted absorption. Iodide substituents effectively red-shift the absorption profile of the dye.
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Transcript of Developing Synergistic Undergraduate Chemistry Labs for Enhanced Student Learning and Integrated...
Developing Synergistic Undergraduate Chemistry Labs for Enhanced Student Learning and Integrated Research Output
Ben Fischer, David Lau, Jennifer Huynh, Christopher Major, Burhan Hussein and Bryan Koivisto*
Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto ON, Canada, M5B 2K3
Chemistry and Biology Department - Second Annual Research Symposium – Wednesday, August 14th, 2013
IntroductionMost traditional undergraduate laboratories focus on reactions to develop basic laboratory techniques using well studied organic reactions; the products of these reactions are seldom studied further. As a result, important structure-property relationships are omitted from practical undergraduate curricula, and products from these labs do not have inherent value outside of technical training. Owing to the expense of basic research, the development of modern synthetic chemistry laboratories, that develop important precursors and building blocks, represents a synergistic opportunity for research and undergraduate education.
Methods: Exposure to Modern Synthetic and Characterization Techniques
This poster describes the development of a new senior undergraduate synthetic laboratory that focuses on the development and study of novel BODIPY compounds. In addition to traditional organic reactions, a myriad of modern synthetic approaches including microwave syntheses, “click” reactions, and Pd-catalyzed cross-couplings are utilized. Furthermore important structure-property relationships are elucidated using physicochemical characterization (UV-Vis, electrochemical properties, theoretical calculations, the appropriate use of Chemdraw, etc.). The following poster presents the first iteration of a newly developed lab where volunteer summer undergraduates focused on the synthesis of 2,6-disubstituted BODIPY analogues (5 derivatives in total).
See Ellie Arnold’s &Burhan Hussein’s poster For more details on how These precursors can be modified
Post Modification and Synthetic Possibilities for Research and Dye Libraries
Characterization: 1H NMR Characterization of Optical Properties using UV-Vis and Density Functional Theory (DFT)
Characterization by Electrochemical Methods:Cyclic Voltammetry
In the Koivisto group at Ryerson University, BODIPY (4,4’-difluoro-4-bora-3a,4a-diaza-s-indacene)-based dyes have garnered considerable attention owing to their highly desirable properties, such as, strong absorption, fluorescence quantum yields, good chemical and photo-stability, and as such have found application in next-generation photovoltaics as non-innocent p-spacers (see above). BODIPYs are synthetically versatile and can be readily tuned using a variety of synthetic techniques. In fact, owing to their non-polar and neutral nature, and their insensitivity to pH and solvent polarity, BODIPY dyes have become ubiquitous for bio-imaging and ion-sensing.
BODIPY fluorophores have spectral characteristics that are often superior to those of fluorescein, tetramethylrhodamine, Texas Red and longer-wavelength dyes, but are very expensive probes for
research laboratories.
data collected in CH2Cl2 using 0.1 M [nBu4N][PF6] at 100 mV/s and referenced to a [Fc]/[Fc]+ internal standard (+ 765 mV vs. NHE in CH2Cl2)
Summary: The Pedagogy of Structure-Property Relationships
AcknowledgmentsA huge thank you to Omar Abdi and Burhan Hussein who were wonderful mentors in the lab and taught us many wonderful techniques. Also a big thank-you goes out to Dr. Koivisto for his guidance and the opportunity to learn in a modern research environment. Finally we would like to thank the Department of Chemistry and Biology for financial assistance in developing this integrated and novel laboratory.
After synthesizing a series of molecules with similar structures, students are then asked to tabulate and examine the effects of functional group modification on the BODIPY core and how it effects the redox and optical properties. Consistent with the the de-shielding observed in the 1H-NMR spectra, both iodides and aldehydes act as electron withdrawing groups; this is also consistent with what is taught in CHY142 and CHY242. In the case of the aldehyde group, the HOMO orbital is stabilized more than the LUMO resulting in a blue-shifted absorption. Iodide substituents effectively red-shift the absorption profile of the dye.
