CAREER: METALLOFOLDAMERS AS ASYMMETRIC CATALYSTS

University Of Delaware, Newark DE

Investigators

Abstract

This research project explores an alternative approach to catalyst design, in which the source of chirality is removed from the primary sphere of metal coordination. This enables one to take full advantage of the large pool of achiral ligands that are available for tuning catalyst reactivity and selectivity. The challenge of ensuring intimate communication between the reaction sphere and the physically separate source of chirality will be addressed through the design of catalytic metallofoldamers that are predisposed to fold into a compact and enantiomerically pure helical structure. The ability of remote chiral centers to control the sense of helicity for metallofoldamers will be studied, and a library of enantiomerically pure salen and salophen complexes that span diverse properties (electronic, bite angle, steric considerations) will be created. The designed catalysts will be utilized in a variety of enantioselective transformations. This research may represent a new paradigm for ligand design in asymmetric catalysis. This program will be integrated with a set of undergraduate and graduate education and training initiatives and the development of a multi-institution research and education consortium. In a collaborative project with a filmmaker, video presentations designed to enhance student understanding and public perception of chemistry will be developed. With the support of this CAREER award from the Organic and Macromolecular Chemistry Program, Professor Joseph M. Fox, of the Department of Chemistry and Biochemistry at the University of Delaware, is exploring new approaches for the synthesis of catalysts designed to carry out selective transformations of organic molecules. His catalysts mimic the means of control utilized by metal-containing enzymes, wherein the environment of the catalyst is strongly influenced and controlled by the surrounding structures, even though they are not directly linked to the metal. This enables one to take full advantage of the large pool of molecules that are available for tuning catalyst reactivity and selectivity while maintaining the requisite high degree of control over the three-dimensional outcome of the catalyzed reactions. Representing a potential paradigm shift in catalyst design, this project offers promise for the development of new and efficient methods for the control of molecular structure. This control is essential in the synthesis of the complex organic molecules generally forming the basis of modern pharmaceutical products. Professor Fox will also develop a set of research and training initiatives designed to enhance the undergraduate and graduate experience, and will produce a series of videos designed to enhance student understanding and public perception of chemistry.