The Chemical Catalysis Program in the Chemistry Division supports this Grant Opportunity for Academic Liaison with Industry (GOALI) award to Professor Bruce Lipshutz. Professor Lipshutz is a faculty member at the University of California, Santa Barbara (UCSB). The project is a collaboration between UCSB and Novartis, a pharmaceutical company. The research undertaken at UCSB focuses on developing new catalysts for valuable organic reactions, where the amount of precious metal, palladium, is only needed in parts per million, rather than the greater levels normally used in palladium-catalyzed reactions. These new reactions reduce the environmental footprint associated with industrial uses of palladium as the reactions are done in water, avoiding use of toxic, flammable, and costly organic solvents. The reagents and experiments under development are of general synthetic utility, and thus may have an impact in academic settings. Students in these research groups learn to couple industrial manufacturing with sustainable chemistry.
New nanoparticles (NPs) are formed by treatment of inexpensive iron(III) trichloride (containing ca. 350 ppm palladium) and a phosphine ligand, with methyl Grignard at room temperature. The new iron nanoparticles (NPs) containing trace palladium metal (Pd) catalyze Suzuki-Miyaura cross-couplings reactions. Synthesis of the Novartis drug valsartan, which contains biaryl residue, is under development using this technology. These NPs are being investigated as catalysts for other important Pd-catalyzed reactions, such as Sonogashira couplings. The reactions are performed in water, thereby eliminating organic solvents as the reaction medium. The NPs can be recycled, effectively reducing not only the amount of Pd needed, but also the levels of residual metal found in the products. In addition, it has been found that these same iron nanoparticles, in the absence of ligand, are effective catalysts for the reduction of aromatic and heteroaromatic nitro groups in water. The reduction leads to the corresponding amine, which is a valuable transformation in the pharmaceutical industry. These new technologies are developed by graduate students, who receive their training both in synthetic organic chemistry and in green chemistry. The students involved in the project are develop the know how to minimize organic and metal waste in reaction development and scale-up.