In this project funded by the Chemical Synthesis program of the Chemistry Division, Professor Paul Floreancig of the University of Pittsburgh is developing environmentally benign approaches to oxidative bond forming reactions in organic synthesis. The advance is achieved through the use of inexpensive, non-toxic stoichiometric oxidants to regenerate quinones and through new transformations that significantly shorten the synthesis of biologically active molecules and their analogs. These efforts provide new routes to access complex structures through carbon-hydrogen bond functionalization in a manner that minimizes waste generation. Professor Floreancig is traveling to colleges and universities that have high populations of students from groups that are traditionally underrepresented in the STEM fields to give seminars and to engage these students in discussions about scientific careers. In addition, Dr. Florencig will use the results of the research carried out under this award as the basis for lectures on green oxidation chemistry.
This project focuses on merging the exceptional capacity to access stabilized carbocations through carbon-hydrogen bond cleavage by the oxidant 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) with the environmental benefits of visible light-mediated photooxidation. DDQ is commonly used in stoichiometric quantities and generates significant quantities of reduction product waste. Visible light-mediated oxidations employ environmentally benign stoichiometric oxidants but do not show broad scope in oxidative cation formation. Using visible light-mediated oxidations to regenerate DDQ from the reduction product provides a path to retaining reactivity while reducing waste formation. Investigating several catalyst systems allow determination of the ideal catalyst structures for this new strategy.
