Synthesis of “Thiocrown 12” for the Stabilization of Cu+ in Titration Experiments
Poster Number
53
College
College of Arts and Sciences
Department
Chemistry, Physics, Geology, & the Environment
Faculty Mentor
Dr. Nicholas Grossoehme & Dr. Jay Hanna
Abstract
Isothermal Titration Calorimetry (ITC) is an ideal method to study binding reactions independently of spectral signatures. The biologically relevant oxidation state of copper, copper (I), is one such “spectroscopically silent” ion. Unlike traditional methods, ITC relies on the generation of a heat signature; as such, it is readily used to quantify thermodynamic properties of Cu+ binding reactions. However, this metal is difficult to study under aqueous conditions due to its sensitivity to oxygen and disproportionation to Cu2+ and Cu0. This project aims to use a cyclical tetrathioether, “thiocrown 12,” for the delivery of chemically stable cuprous ions to systems of interest. The thiocrown synthesized is desirable due to the four coordinate tetrahedral geometry that the cavity presents. Recognition of these qualities led this research to continue in the synthesis of the thiocrown. Through the reaction of “dibromopropanediol 3” with Na2S the cyclized “thietane 9” product was obtained in high yield and purity. The product was confirmed by Gas Chromatography Mass Spectrometry (GC Mass Spec) and comparison to literature 1H-NMR. “Diiodide 10” was produced by reacting “thietane 9” with diiodopropane; however, the literature conditions for this reaction were unusable. To get around this, a system was optimized for the microwave synthesis of “diiodide 10,” significantly dampening the time needed for the synthesis. The most effective conditions were found to be 135oC for 10 hours.
Previously Presented/Performed?
Summer Undergraduate Research Experience (SURE) Symposium, Winthrop University, July 2015
Grant Support?
Supported by grants from the National Institutes of Health IDeA Networks for Biomedical Research Excellence (NIH INBRE) and the Winthrop University Research Council
Start Date
22-4-2016 2:15 PM
End Date
22-4-2016 4:15 PM
Synthesis of “Thiocrown 12” for the Stabilization of Cu+ in Titration Experiments
Richardson Ballroom
Isothermal Titration Calorimetry (ITC) is an ideal method to study binding reactions independently of spectral signatures. The biologically relevant oxidation state of copper, copper (I), is one such “spectroscopically silent” ion. Unlike traditional methods, ITC relies on the generation of a heat signature; as such, it is readily used to quantify thermodynamic properties of Cu+ binding reactions. However, this metal is difficult to study under aqueous conditions due to its sensitivity to oxygen and disproportionation to Cu2+ and Cu0. This project aims to use a cyclical tetrathioether, “thiocrown 12,” for the delivery of chemically stable cuprous ions to systems of interest. The thiocrown synthesized is desirable due to the four coordinate tetrahedral geometry that the cavity presents. Recognition of these qualities led this research to continue in the synthesis of the thiocrown. Through the reaction of “dibromopropanediol 3” with Na2S the cyclized “thietane 9” product was obtained in high yield and purity. The product was confirmed by Gas Chromatography Mass Spectrometry (GC Mass Spec) and comparison to literature 1H-NMR. “Diiodide 10” was produced by reacting “thietane 9” with diiodopropane; however, the literature conditions for this reaction were unusable. To get around this, a system was optimized for the microwave synthesis of “diiodide 10,” significantly dampening the time needed for the synthesis. The most effective conditions were found to be 135oC for 10 hours.
