Welcome to the latest RSC Desktop Seminars, sponsored by Chemical Science, ChemComm and Chem Soc Rev. Each session will highlight two speakers, one journal board member and an early career researcher who has published in the journal.
Join Jennifer Love, Professor of 91AV at University of Calgary and Editorial Board Chair of Chem. Soc. Rev., and Neal Mankad, Associate Professor of 91AV at the University of Illinois at Chicago, to hear about their latest work.
This 90 minute seminar will allow researchers of all professional levels to connect and share ideas and questions.
"Towards catalytic methane functionalization with Pt complexes"
The ability to convert methane into more useful, functionalised compounds has been a long-standing goal in organometallic chemistry. The first step to functionalising methane is to cleave one of the strong carbon-hydrogen bonds. Considerable efforts have been made to active the carbon-hydrogen bonds of methane in a controlled fashion (e.g., cleavage of only on C-H bond). The challenge is that most products of methane functionalisation have weaker bonds than methane and are therefore more susceptible to activation than methane, leading to undesired by-products in large quantities. Late transition metals, such as platinum, have been shown to be quite effective in breaking strong C-H bonds. We have recently explored the feasibility of catalytic methane functionalization employing aryl halides as oxidants. I will discuss our results solving some key challenges, including using aryl halide oxidative addition with Pt(II) complexes. We have recently developed new hemilabile P,N ligands that readily promote both oxidative addition and reductive elimination, and will compare these new ligands to more conventional N,N or P,P ligands. Notably, there is a significant and surprising role of sterics: only P,N ligands with significant steric bulk at phosphorus were capable of forming the strained Pt(II) chelates. These results will be discussed in the context of our ongoing efforts to catalytically functionalise methane.
Neal Mankad
“Synthetic modeling of the heterobinuclear Mo/Cu active site in aerobic carbon monoxide dehydrogenase (CODH)”
CO is oxidized to CO2 on a 108 ton/year scale by chemolithoautotrophic microorganisms that help maintain carbon homeostasis in the geochemical carbon cycle. Detailed understanding of the carbon monoxide dehydrogenase (CODH) enzymes catalyzing this conversion will aid bioinspired designs of synthetic catalysts for carbon cycling and chemical energy storage. Aerobic bacteria and archaea feature a Mo/Cu-dependent CODH whose catalytic active site has long been a target for synthetic modeling. In this presentation, our group’s recent and ongoing efforts to build structurally faithful synthetic models will be discussed. Most notably, a synthetic W/Cu analogue was synthesized and represents the closest structural mimic of the catalytic Mo/Cu cofactor reported to date. Lessons about biochemical CO oxidation gained from comparing the “relaxed” synthetic cofactor to the “strained” native cofactor will be presented.
10.05 “Towards catalytic methane functionalization with Pt complexes” - Professor Jennifer Love
10.55 “Synthetic modeling of the heterobinuclear Mo/Cu active site in aerobic carbon monoxide dehydrogenase (CODH)” - Professor Neal Mankad
11.30 Closing remarks
Join Jennifer Love, Professor of 91AV at University of Calgary and Editorial Board Chair of Chem. Soc. Rev., and Neal Mankad, Associate Professor of 91AV at the University of Illinois at Chicago, to hear about their latest work.
This 90 minute seminar will allow researchers of all professional levels to connect and share ideas and questions.
Speakers
Jennifer Love"Towards catalytic methane functionalization with Pt complexes"
The ability to convert methane into more useful, functionalised compounds has been a long-standing goal in organometallic chemistry. The first step to functionalising methane is to cleave one of the strong carbon-hydrogen bonds. Considerable efforts have been made to active the carbon-hydrogen bonds of methane in a controlled fashion (e.g., cleavage of only on C-H bond). The challenge is that most products of methane functionalisation have weaker bonds than methane and are therefore more susceptible to activation than methane, leading to undesired by-products in large quantities. Late transition metals, such as platinum, have been shown to be quite effective in breaking strong C-H bonds. We have recently explored the feasibility of catalytic methane functionalization employing aryl halides as oxidants. I will discuss our results solving some key challenges, including using aryl halide oxidative addition with Pt(II) complexes. We have recently developed new hemilabile P,N ligands that readily promote both oxidative addition and reductive elimination, and will compare these new ligands to more conventional N,N or P,P ligands. Notably, there is a significant and surprising role of sterics: only P,N ligands with significant steric bulk at phosphorus were capable of forming the strained Pt(II) chelates. These results will be discussed in the context of our ongoing efforts to catalytically functionalise methane.
Neal Mankad
“Synthetic modeling of the heterobinuclear Mo/Cu active site in aerobic carbon monoxide dehydrogenase (CODH)”
CO is oxidized to CO2 on a 108 ton/year scale by chemolithoautotrophic microorganisms that help maintain carbon homeostasis in the geochemical carbon cycle. Detailed understanding of the carbon monoxide dehydrogenase (CODH) enzymes catalyzing this conversion will aid bioinspired designs of synthetic catalysts for carbon cycling and chemical energy storage. Aerobic bacteria and archaea feature a Mo/Cu-dependent CODH whose catalytic active site has long been a target for synthetic modeling. In this presentation, our group’s recent and ongoing efforts to build structurally faithful synthetic models will be discussed. Most notably, a synthetic W/Cu analogue was synthesized and represents the closest structural mimic of the catalytic Mo/Cu cofactor reported to date. Lessons about biochemical CO oxidation gained from comparing the “relaxed” synthetic cofactor to the “strained” native cofactor will be presented.
Programme (EDT)
10.00 Introduction10.05 “Towards catalytic methane functionalization with Pt complexes” - Professor Jennifer Love
10.55 “Synthetic modeling of the heterobinuclear Mo/Cu active site in aerobic carbon monoxide dehydrogenase (CODH)” - Professor Neal Mankad
11.30 Closing remarks
