Robert H. Grubbs
Organometallic Synthesis and Mechanisms: The group examines the fundamental organometallic chemistry required for the design and synthesis of catalysts for use in organic and polymer synthesis. Catalysts for olefin metathesis have been the focus of the research over the past several years. A family of ruthenium catalysts has been developed that has opened a wide variety of applications for olefin metathesis. The tolerance of these catalysts to functional groups and their ease of use have been the keys to their broad use. Underlying the development and improvement in these catalysts has been a detailed understanding of their mechanism of reaction. Continuing efforts are being made to further improve and broaden the use of these catalysts. These studies involve ligand and new transition metal complex synthesis as well as continuing examination of the mechanistic features that control the activity and selectivity of these catalysts. Recently the Division has created the Center for Catalysis and Synthesis. Our group is using the center for the rapid screening for the new catalyst systems.
Organic Synthesis and Reagents: Over the past several years a number of olefin metathesis based transformation have become important in organic synthesis. The most broadly use method is ring closing metathesis (RCM) to form a variety of rings. Five to over 82 membered rings have been prepared in good yield using olefin metathesis. The functional group tolerance of the ruthenium based catalyst allows complex molecules to be prepared without protecting groups. Definition of the rules controlling the use of cross metathesis in organic synthesis has opened its application to the synthesis of a variety of functional molecules. A variety of related reactions involving tandem and acetylene metathesis are also being used. The focus of the group at this time is on the sysnthesis of more active and selective systems. Catalysts that provide high enantioselectivity in RCM and high stereoselectivity in cross metathesis are being developed. Other metal catalyzed reactions that provide new routes to acetylenes and alcohols are being studied.
Polymer Synthesis: Ring opening metathesis polymerization (ROMP) has opened new methods for the synthesis of highly functionalized polymers with controlled structures. By tuning of the structure of the ruthenium based metathesis catalysts, the opportunities have been greatly expanded. Recent methods have been developed that are being used to prepare cyclic olefins, alternating copolymers and multiblock copolymers with a broad array of functionality. The properties and applications of these new materials are being explored.