This award in the Chemical Synthesis (SYN) program supports work by Professor Richard R. Schrock at the Massachusetts Institute of Technology to carry out fundamental studies on olefin metathesis catalysts based on molybdenum or tungsten. Olefin metathesis is a catalytic reaction that consists of breaking and rearranging carbon-carbon double bonds in organic molecules. The benefit of the reaction to mankind was recognized through the 2005 Nobel Prize in Chemistry to Schrock, Grubbs, and Chauvin. New developments in the last two years have led to new types of molybdenum and tungsten catalysts that are much more reactive and selective than any previous catalysts. The proposed work includes an investigation of the interconversion and relative reactivity of syn and anti alkylidene isomers and devising routes to new MonoAlkoxide Pyrrolide (MAP) catalysts and related species, including selective catalysts supported on silica or alumina.
The olefin metathesis reaction has revolutionized the synthesis of organic molecules relevant to natural and unnatural products for treatment of diseases such as cancers and AIDS, as well as the synthesis of specialty polymers. Newly developed applications include the synthesis of organic molecules from renewable resources such as seed oils and the selective synthesis of organic molecules that contain only a cis carbon-carbon double bond, the type that is most common in natural products and the most useful in organic synthesis.
This project is aimed at developing a fundamental understanding of a catalytic reaction in which carbon-carbon double bonds can be rearranged to form a different set of carbon-carbon double bonds, and that employ catalysts that contain molybdenum (Mo) or tungsten (W). The reaction was discovered approximately fifty years ago and is called the Olefin Metathesis Reaction. Beginning in the mid 1980's catalysts were prepared, identified, and varied for carrying out the many variations of the basic metathesis reaction. These catalysts contain a metal-carbon double bond and the crucial step is a combination of a metal-carbon double bond and a carbon-carbon double bond to form a four-membered ring that contains the metal and four carbons. A related version of the olefin metathesis reaction is the acetylene metathesis reaction, in which carbon-carbon triple bonds are rearranged to form new carbon-carbon triple bonds. The major finding in the last four years of research in olefin metathesis have been a method of making selectively two types of new carbon-carbon double bonds. One is called a cis C=C bond. The ability to make solely cis C=C bonds has been an outstanding goal in the field for nearly fifty years. The other type that can now be made selectively is a trans C=C bond. The ability to make one or the other is crucial to the synthesis of one product instead of a mixture. Olefin metathesis has been said to be one the most significant contributions to chemistry in the last 50 years. It has revolutionized much of organic chemistry and polymer chemistry and has led commercial processes in the areas of seed oils, fragrances, polymers, materials, and pharmaceuticals. A measure of the importance of this work was a Nobel Prize in Chemistry in 2005 "for the development of the metathesis method in organic synthesis" (shared by myself, R. H. Grubbs and Y. Chauvin), which is typically work that is judged by the Nobel committee to be of greatest benefit to mankind. The evolving impact of Mo and W metathesis chemistry on organic, polymer, pharmaceutical, fragrance, seed oil, agro, and materials chemistries, led to the founding of a company called XiMo in the fall of 2010 that is devoted to the commercialization of Mo and W metathesis catalysts. Over a dozen patents have been filed by MIT that concern some aspect of olefin metathesis. I have had many opportunities to lecture to the public, as well as other scientists, on the latest results and new directions for future research in olefin metathesis. One of the most dramatic are week long visits to the Nobel meeting for chemistry in Lindau, Germany. In 2013 34 Nobel Laureates and 635 young scientists from 78 countries came to Lindau to exchange knowledge and acquire more enthusiasm for science. I spent the week with student groups at lunches, dinners, and a variety of interviews, panels, and public discussions. As of June 2014 I have supervised a total of 81 PhD students and a total of 94 postdoctoral students. Most of these students accept permanent positions in industry or academia.
