The Chemical Catalysis Program of the NSF Division of Chemistry supports the research efforts of Professor Gojko Lalic of the University of Washington to investigate new general strategies for the hydrofunctionalization of unsaturated compounds using transition metal catalysis. The research group is first studying the highly selective copper-catalyzed reduction of alkynes to alkenes. This practical method avoids common side reactions such as over-reduction and alkene isomerization. Copper-catalyzed anti-Markovnikov hydrobromination reactions of terminal alkynes are also under investigation. These new catalytic reactions for the preparation of alkenyl bromides provide valuable alternatives to stoichiometric methods currently used for the synthesis of this class of compounds. A third aim of Professor Lalic's copper-catalyzed chemistry is the synthesis of Z- and E-alkenes via the hydroalkylation of alkynes. Finally, the research group is investigating a new general approach to the asymmetric synthesis of quaternary stereocenters based on gold-catalyzed hydrofunctionalization of chiral allenes. Using this approach, new methods for the synthesis of enantioenriched tetrahydrofurans, tetrahydropyrans, chromans, pyrroles, piperidines, and a variety of carbocyles containing quaternary stereocenters are under investigation. In addition to providing valuable tools for organic synthesis, Prof. Lalic is active in promoting STEM education at two local high schools by contributing to guest lectures and participating in school science fairs and in Seattle-area science exhibits.
The selective reduction of triple bonds to double bonds is a common and important transformation in organic chemistry. These reactions are currently achieved using a 5% by weight palladium catalyst (Lindlar catalysts) which makes it very expensive. Furthermore, the current transformations can be unpredictable - leading to the formation of unwanted single bonds (alkane compounds) and so the reaction must be closely monitored to achieve high levels product formation or a significant amount of waste will form and need to be separated and disposed of, again, increasing the cost of materials and energy associated with the commercial processes. Professor Lalic and his group at the University of Washington are preparing new, relatively inexpensive, copper catalysts that will take the place of palladium in the selective conversion of triple bonds (alkyne compounds) to double bonds (alkene compounds). These reactions are especially important because they use earth abundant metals which provide reliable and sustainable access to organic compounds which are important in medicines and pharmaceuticals as well as in other fine chemicals. In additional to providing his students with excellent laboratory training in organic synthesis, Dr. Lalic has established and maintained a database of problems in organic and organometallic chemistry that is available to the academic community. Professor Lalic seeks to address non-representative participation of minorities and women in science by contributing to science enrichment programs. These efforts - guest lectures at West Seattle High School and Ingraham High School, participation in the Hamilton International Middle School Science Fair, and participation in the Seattle-area science exhibit called Paws on Science at the Pacific Science Center and the University of Washington - promote chemistry as a career choice among elementary and middle school students.
