John C. Dewan

Bio: John C. Dewan is an academic researcher from Massachusetts Institute of Technology. The author has contributed to research in topics: Imidazolate & Reactivity (chemistry). The author has an hindex of 22, co-authored 54 publications receiving 1547 citations. Previous affiliations of John C. Dewan include New York University.

Ruthenium-based heterocyclic carbene-coordinated olefin metathesis catalysts.

Abstract: The fascinating story of olefin (or alkene) metathesis (eq 1) began almost five decades ago, when Anderson and Merckling reported the first carbon-carbon double-bond rearrangement reaction in the titanium-catalyzed polymerization of norbornene. Nine years later, Banks and Bailey reported “a new disproportionation reaction . . . in which olefins are converted to homologues of shorter and longer carbon chains...”. In 1967, Calderon and co-workers named this metal-catalyzed redistribution of carbon-carbon double bonds olefin metathesis, from the Greek word “μeτάθeση”, which means change of position. These contributions have since served as the foundation for an amazing research field, and olefin metathesis currently represents a powerful transformation in chemical synthesis, attracting a vast amount of interest both in industry and academia.

Structural and functional analogues of the active sites of the [Fe]-, [NiFe]-, and [FeFe]-hydrogenases.

Abstract: This article sets out to review the chemistry relating to the synthesis of structural and functional analogues of the three classes of hydrogenases. This chemistry has grown explosively over the last 10 or so years since the first X-ray structures of [NiFe]- and [FeFe]-hydrogenase systems were published. There are now some 400 papers covering structural and functional aspects, with the majority of these associated with the di-iron system. As much emphasized in earlier papers

Ring-Closing Metathesis and Related Processes in Organic Synthesis

Abstract: Carbon-carbon bond forming reactions remain among the most important for the synthesis of organic structures. The transition metal alkylidene-catalyzed olefin metathesis reaction (eq 1) and the related transition metal alkylidene-mediated carbonyl olefination reaction (eq 2) are two such processes. Historically, olefin metathesis has been studied extensively both from the mechanistic standpoint and in the context of polymer synthesis. In contrast, its application to the synthesis of complex organic molecules and natural products has been limited. The related reaction, transition metal-mediated carbonyl olefination, is not as extensively studied mechanistically nor in synthetic applications. Among the reasons for this gap in methodology has been the incompatibility of traditional catalysts with the polar functional groups typically encountered in organic synthesis.