Discipline: Chemistry and Chemical Sciences
Subcategory: Chemistry (not Biochemistry)
Sofia Valiente Suarez - University of Puerto Rico- Mayaguez Campus
Co-Author(s): Joan E. Roque, Westminster College, Salt Lake City, UT ; Hannah Shenouda, The University of North Carolina at Chapel Hill, Chapel Hill, NC ; Erik J. Alexanian, The University of North Carolina at Chapel Hill, Chapel Hill, NC
Olefins are key chemical feedstocks in the synthesis of natural products, pharmaceuticals, and agrochemicals. A variety of methods to make alkenes have been developed; one is through -hydride elimination, a typically undesired pathway in transition metal catalyzed cross coupling reactions. Cobalt is an inexpensive alternative to other commonly used transition metal catalysts; i.e., palladium. Our goal was to investigate the efficiency of cobalt for achieving the dehydrohalogenation of alkyl tosylates. Preliminary results show that 27% of the alkene can be obtained when using a secondary tosylate as the substrate and potassium cobaltate, K[Co(CO)4], in stoichiometric quantities. This suggests that cobalt can be used to accomplish the dehydrohalogenation of pseudohalides. Optimization is ongoing.abstract UNC poster .docx
Funder Acknowledgement(s): NSF REU program (CHE-1460874)
Faculty Advisor: Erik J Alexanian, email@example.com
Role: My role in the project was preparing the starting material and running test reactions. I would screen bases, solvents, reaction temperatures and reaction atmospheres. I would make my reaction inside the glove box and then leave them stirring overnight. The next day, I would work the reactions up, go to the NMR (nuclear magnetic resonance), and analyze the molecules according to their spectrum. I did achieve the ß-hydride elimination of the alkyl tosylate using the following conditions: a reaction temperature of 70°C, a reaction atmosphere of hydrogen, PMP (pentamethyl piperidine) as the base, and a 1 to 1 mixture of ethanol and n-heptane as the solvent. This preliminary result gave the researchers at the Alexanian laboratory many ideas on how to optimize the reaction.