报告人:Prof. Douglas W. Stephan, Department of Chemistry, University of Toronto, Canada
时间:2019年3月4日(星期一)下午16:00-17:30
地点:A204
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Abstract
In 2006, we found that combinations of Lewis acids and bases in which steric demands preclude dative bond formation can activate H2. This discovery has allowed the application of main group Lewis acids and bases in catalysis. This concept known as “frustrated Lewis pairs” (FLPs), has led to the development of metal-free hydrogenation catalysis. Recent studies have suggested both hemolytic and heterolytic mechanisms of action, dependent on the nature of the FLP. Moreover, the design of new FLP catalysts has uncovered new highly electrophilic phosphonium cationic Lewis acids. These have been shown to be effective for C-F bond hydrodefluorination catalysis, hydrosilylations, hydrogenations and C-F bond functionalization and hydroarylation of alkynes among other applications. The concept of FLPs has also been applied to the activation of a variety of other small molecule activations, with key targets being CO2 and N2 reduction. These developments demonstrate the utility of main group species in catalysis, offering alternatives to conventional transition metal based catalysts. The implications for the future will be considered in this lecture.