CAREER: Roadmaps for Developing Hypervalent Phosphorus-Based Main Group Catalysts and Bridging Gaps in STEM Education in Hawaii

University Of Hawaii, Honolulu

Investigators

Abstract

A catalyst is a substance that speeds or facilitates a chemical reaction. Catalysts are critical to the chemical and pharmaceutical industries where they are used to reduce energy requirements of chemical processes and to orient precise chemical transformations. Many of the most active catalysts are based on rare metals that are quite costly and difficult to find and isolate. An important area of current research seeks to find cheap, abundant replacements for these expensive catalysts. Phosphorus (P) is an abundant, inexpensive element. However, there has been little effort made to devise catalysts based on it. Dr. Matthew Cain, Department of Chemistry, University of Hawaii at Manoa, is supported by the Chemical Synthesis Program of the Chemistry Division, to prepare unusual compounds where phosphorus atoms are in unusual oxidation states and may behave like metals under certain circumstances. Thus, phosphorus may represent an alternative to the rare, expensive metal catalysts currently being used. This research may lead to highly unusual catalysts which could have transformative impact - replacing expensive and toxic platinum group metals in major industrial and pharmaceutical reactions. In addition, this project includes an educational component that is designed to attract Native Hawaiian students into science. Native Hawaiians, although they constitute a sizable fraction of the population in the State of Hawaii, are very underrepresented in science and technology. Thus, this aspect of the projects provides an important, new opportunity to the Native Hawaiian population. Using monoanionic pincers featuring an equatorial carbon-aryl donor and electron-withdrawing axial donors, hypervalent 10-P-3 species with the correct frontier orbital environment to promote oxidative addition are prepared. Fundamental studies on coordination and insertion of unsaturated substrates and reductive elimination from 10-P-5 centers probe the feasibility of closing a potential catalytic cycle. Ultimately, 1,2-difunctionalization, particularly, hydrogenation, hydrosilation, and diboration of simple organic substrates is tested with 10-P-3 catalysts. In addition, the project is developing a three-tiered approach of exposing, attracting, and inspiring the Native Hawaiian and Asian-American/Hawaiian-born population to become involved in science, technology, engineering, and mathematics. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.