Rudolf Wehmschulte & Samuel Dagorne
Biography - Rudolf Wehmschulte
Rudi Wehmschulte is a professor of chemistry in the Department of Chemistry and Chemical Engineering at the Florida Institute of Technology in Melbourne (Florida, United States). During his USIAS Fellowship, he will be hosted by his co-Fellow Samuel Dagorne at the Institute of Chemistry.
His research interests center on the chemistry of cationic, very strong Lewis acids and eventually developed into the investigation of the chemistry of “naked” cations, i.e. cations that are only weakly coordinated to the counterions and/or the solvent. This is made possible by the use of carborate ions, which are chemically largely inert and aesthetically pleasing icosahedral cage compounds.
He obtained his doctorate (Dr. rer. nat.) under the supervision of Professor Josef Grobe at the University of Münster (Germany) in 1991, working on nickel complexes with tripodal ligands. During his post-doctoral stay with Professor Philip Power at the University of California in Davis, he focused on organometallic main-group chemistry, mostly involving organoaluminum compounds. He began his independent career at the University of Oklahoma in Norman in 1998, from where he moved to the Florida Institute of Technology in 2005, where he now holds the rank of Professor.
In his spare time, he applies large scale biochemical reactions involving the enzymatic conversion of starch (mostly from barley malt) into sugars, followed by thermal isomerization of bittering compounds (mostly a- and b- acids), and finished by single-cell organism mediated transformation of the sugars into ethanol.
Biography - Samuel Dagorne
Samuel Dagorne is a CNRS research director at the Institute of Chemistry of Strasbourg (IC), a joint research unit of the University of Strasbourg and the French National Centre for Scientific Research (CNRS).
His research focuses on the synthesis and study of the reactivity of electrophilic organometallics, as well as on the polymerization catalysis of polar monomers using organometallic and organic catalysts/initiators.
Dr. Dagorne obtained his undergraduate degree at the University of Rennes (France) in 1994. In 1995, he joined the group of Professor Richard F. Jordan at the University of Iowa (United States) and graduated with a PhD working on chiral zirconocenes and group 13 compounds. In 1999, he joined Professor Richard R. Schrock’s group at the Massachusetts Institute of Technology (MIT), United States, as a post-doc working on molybdenum alkylidenes.
Back in France, he joined the CNRS in 2000 at the École nationale supérieure de chimie de Paris (ENSCP) and moved to the University of Strasbourg in 2006. Since 2015, he has led the SRCO team (Synthesis, Reactivity and Organometallic Catalysis) at the Institute of Chemistry.
Fellowship 2023
Dates - 01/12/2023-31/12/2025
Project summary
TOWARDS MONO-COORDINATE AND “NAKED” M2+ FIRST-ROW TRANSITION METAL DI-CATIONS IN THE CONDENSED PHASE AS STRONG LEWIS ACIDS: SYNTHESIS AND EXPLORATION OF THEIR REACTIVITY
In solutions of metal salts, the metal cation is typically coordinated by ligands, which can include the counterions, solvent molecules or other molecules with an affinity for the metal cation. The metal ligand interactions influence the properties of the metal cation itself, and in the case of catalytic reactions, such interactions could compete with the bonding/activation of the substrate. To date, the properties of “naked” metal cations, i.e. cations without the counterions and other ligands, can only be studied in the gas phase. This requires complex equipment and is limited to minute amounts of material.
Our groups have developed systems in which gas-phase-like conditions are approached in the condensed phase. This is achieved using large and chemically inert counterions that only interact weakly with the metal cation. In addition, these counterions facilitate the solubility of “simple” MX2 salts in low polarity organic solvents with only weak cation solvent interactions. Based on our recent and current results with zinc and magnesium salts, this project will focus on the synthesis of first-row transition metal salts including manganese, iron, cobalt, and nickel. These ions are similar in size to zinc and magnesium, but their electronic properties are expected to be fundamentally different due to the partially filled 3d orbitals shell likely resulting in exciting new chemistry and possibly unprecedented reactivities.
We will determine the chemical and physical properties of these new salts and will then investigate their capability to mediate olefin hydrosilylation, transfer hydrogenation of olefins and olefin hydrogenation reactions.
Other information and news (activities, project staff, publications...)
Geetika Gupta (post-doctorate) holds a PhD (2016) in inorganic chemistry from Banaras Hindu University, India. Her doctoral thesis was focused on the development of polynuclear heterobimetallic metal thiolate clusters. After completing her PhD, she was awarded a prestigious National Post Doctoral Fellowship (N-PDF) to continue studies at the Indian Association for the Cultivation of Science (IACS). There, she explored high-valent iron-oxygen species before moving to the Indian Institute of Technology Delhi, where she developed bioinspired high-valent manganese-oxo species for bio-relevant substrate oxidation.
Dr. Gupta's passion for research led her to join Samuel Dagorne's team in the Institute of Chemistry at the University of Strasbourg as a USIAS post-doctoral researcher. Her work, focusing on synthesis and reactivity studies of low-coordinated first-row transition metals as strong Lewis acids, holds great promise for further advancements in the field.
