NOVEL DEOXYGENATION-DIMERIZATION OF BENZOISOTHIAZOLONES
Juan Cisneros, Pavan Kumar Reddy Gangireddy, Lanny Liebeskind.
Emory University, Atlanta, GA.
The Liebeskind group is developing an organo-catalytic redox system to drive dehyrdative coupling chemistry. Dehydrative coupling is not only vital to biological systems but is also a very useful tool for a variety of industry sectors including energy, pharmaceuticals, and others. Our oxidation-reduction condensation reaction involves an organic oxidant, a benzoisothioazolone (BIT) and triethyl phoshite as our organic reductant. As Dr. Gangireddy first discovered, reacting these 2 in solution produces an unexpected and interesting product resulting from a deoxygenation-dimerization of the BIT. Our study focuses on the scope of this dimerization reaction with the intent of exploring its generality and optimizing the reaction conditions. Running these reactions in varying temperatures, solvents, and BIT molecules will provide a deeper understanding of the processes and help deliver a general and efficient reaction. Reactants, reaction progression, and products were analyzed and characterized using 1H, 31P, and 13C nuclear magnetic resonance spectroscopy. Further analysis was done using thin layer chromatography, infrared spectroscopy, mass spectrometry, and X-ray crystallography. Having experimented with a few BIT molecules and several different reaction conditions, the original observation of Dr. Gangireddy still stands and BIT-deoxygenation-dimerization is proving to be generalizable with substituent variance. Further study will help us to understand differences in yields and extraction difficulties and arrive at a general and informative library of BIT-deoxygenation dimers. Having a comprehensive library will then allow for the study of developing these BIT-dimers into larger complexes with possible metal coupling and a look into their c-2 symmetry and enantiocontrol running metal-catalyzed reactions.