GOALI: Development of General Methods to Access Functional Arylalkoxysilanes

The University Of Central Florida Board Of Trustees, Orlando FL

Investigators

Abstract

With the support of the Chemical Synthesis program of the Division of Chemistry of the National Science Foundation, Professor Kangsang Lee, Department of Chemistry at the University of Central Florida, is supported to develop general methods for the preparation of functional arylalkoxysilanes. Silicones are very widely used materials and are found in common consumer products such as bottles, cosmetic products, and cookware as well as in high-tech automotive, electronic, aeronautic and biomedical applications. A group of compounds called alkoxysilanes are the most common building blocks in the manufacture of silicone materials. However, their utility is limited due to difficulties in preparing subtle variations of them. However, there is another group of potential silicone building blocks called arylalkoxysilanes that potentially can overcome the limitations of the alkoxysilanes. A major problem faced in employing this class of building blocks is that methods the efficiently prepare them are not known. Thus, this project aims at developing a direct and atom-economical pathway to synthesize a wide variety of arylalkoxysilanes. The project involves a close collaboration between Professor Lee’s group and scientists at Dow Chemical Company. This collaboration and the access to facilities at Dow permits the advances made in Professor Lee’s laboratories to be efficiently evaluated for their potential in the industrial manufacture of silicones. Additionally, it provides exemplary educational experiences to the students who will be engaged in the project. This project will develop a number of catalytic C–H silylation reactions involving arenes and heteroarenes. Carbon-hydrogen silylation reactions are currently limited to reactive hydrosilanes such as trialkylsilanes and siloxyhydrosilanes and result in arylsilanes that cannot be directly utilized in siloxane polymer synthesis. More desirable building blocks in silicone syntheses are alkoxy-containing arylsilanes. However, only a few of these are available due to the lack of efficient synthetic methodologies. To address this problem this project an efficient rhodium catalyzed C–H silylation between unactivated (hetero)arenes and mono-, di- or trialkoxyhydrosilanes is being developed. The process is designed to provide a general methodology to a variety of arylalkoxysilanes. The project involves close collaboration between Professor Lee’s group and scientists at Dow Chemical Company. The industrial partner will provide expertise and the facilities for in high-throughput screening to identify potential catalysts and will apply these results to uncover structure-property relationships to guide further synthetic efforts. Additionally, the new arylalkoxysilanes will be evaluated as precursors to polymeric materials. This aspect of the project will involve internships, which will provide rich industrial experiences to the students involved. 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.