Our next webinar will take place via the internet on Tuesday November 8th at 10 AM EST/3 PM GMT. Sign up on our mailing list to receive the Zoom link!
We hope to see/hear from you all at one of our sessions or as one of the next speakers. If you are an early career scientist and would like to present your research, don't hesitate to submit an abstract today! For now, please learn more about our current speakers and their research below. We also thank the generous support from Cell Reports Physical Science, Merck, Janssen, and the Royal Society of Chemistry.
Our featured speakers this week are Marianna (Mina) Head (Undergraduate Student, Colgate University, USA), and Dr Patrick Robertson (Postdoctoral Researcher, Oxford University, UK).
LEARN MORE ABOUT THE SPEAKERS AND THEIR TALKS BELOW
MARIANNA HEAD (on Twitter @mchead12)
Biography: I am a senior Chemistry and Philosophy major at Colgate University in Hamilton, NY. In 2021, I joined Prof. Anthony Chianese's lab, where I primarily study hydrogenolysis reactions catalyzed by pincer-ruthenium catalysts. With the hope of continuing my education in chemistry, I plan to apply to graduate school this fall.
Title of Talk: Mechanistic Studies of Markovnikov-Selective Epoxide Hydrogenolysis Catalyzed by Ruthenium PNN and PNP Pincer Complexes
Abstract: Pincer-ruthenium catalysts provide a method for the hydrogenolysis of various polar functional groups including imines, esters, ketones, and amides. However, the hydrogenolysis of epoxides by this breed of catalyst has been studied less extensively. Our group recently reported the Markovnikov-selective hydrogenolysis of epoxides in 2-propanol, using two ruthenium pincer complexes bearing an N-H group close to the metal center. A mechanistic study using density functional theory alongside experimental kinetic analysis supports a mechanism that involves an opposite-side attack of the ruthenium hydride on the terminal carbon of the epoxide, instead of the Noyori-type, same-side attack that is common in the hydrogenolysis of related functional groups. Through our computational work, we predicted rate laws for both catalysts using the energetic span model and the kinetic data was consistent with these predictions. The hydrogenolysis of epoxides by Ru-pincer catalysts is a synthetic route to branched alcohol products that is more atom-economical than some traditional approaches involving stoichiometric hydride donors.
DR PATRICK ROBERTSON (on Twitter @ghett_smart)
Biography: Patrick did his PhD in molecular spectroscopy at La Trobe University in Melbourne, Australia. He was a postdoc at the University of Bristol working for Prof Andrew Orr-Ewing from 2019-2021, he then took up a position in Prof Claire Vallance's group University of Oxford. His research interest focus on energy and time resolved chemical reaction dynamics in the gas-phase and in solution.
Title of Talk: Covariance-map Imaging: Unraveling Unintuitive Dynamics in Electron Impact Ionization
Abstract: Electron impact ionization is a common mass spectrometric ionization method, and understanding the complex chemistry it can invoke has implications in astrochemical and biological context. Using covariance analysis, in conjunction with velocity map imaging and time-of-flight mass spectrometry we can unravel the complex dynamics of the ion chemistry initiated by electron-molecule collisions. In this study of C2F6, we observe competing channels for dissociation, mechanistic switching, as well as highly unintuitive rearrangement of multiply-charged ions. The results show the power of the covariance-mapping technique for extracting important correlations in minor product channels, and shed light on the complex mechanisms in the formation of plasmas.