Zukünftige Termine
- 2023-10-17T17:00:00+02:00
- 2023-10-17T19:00:00+02:00
David W. Christianson, University of Pennsylvania
Directing Biosynthesis with Modular Architecture in Terpene Cyclases Terpene cyclases catalyze the most complex chemical reactions in biology, in that more than half of the carbon atoms in an isoprenoid substrate undergo changes in bonding or hybridization during a multi-step cyclization cascade that proceeds through multiple carbocation intermediates. Although the substrate pool for these enzymes is limited to only a handful of linear isoprenoids, more than 100,000 terpenoid natural products have been identified to date. Crystal structures of terpene cyclases reveal common, modular protein folds that direct unique catalytic strategies underlying this exquisite chemodiversity. Most recently, structural studies of bifunctional assembly-line terpene synthases using cryo-EM and other biophysical techniques show how the first two steps of terpene biosynthesis are combined in nanoscale oligomeric assemblies.
- 2023-10-24T10:00:00+02:00
- 2023-10-24T12:00:00+02:00
Dr. Francisco Juliá-Hernández, University of Murcia
"Illuminating Earth-abundant Metals: New Opportunities in Organic Synthesis" Visible-light photoredox catalysis has driven the evolution towards more efficient and sustainable syntheses to build up molecular complexity via single-electron transfer (SET) events. State-of-the-art photocatalysts, commonly made by precious metals or organic compounds, promote this key SET via an outer-sphere mechanism, in which a match between the redox potentials of photocatalyst and substrate is required. Although outstanding advances have been accomplished, this redox limitation has hampered the expansion of the scope of these transformations. In my talk, I will summarize my group’s efforts to overcome these challenges with the design of Earth-abundant metal photocatalysts, made of inexpensive and readily available base-metals, which operate via a complementary mode of action from traditional photoredox catalysts, outperforming their activity.
- 2023-10-31T17:00:00+01:00
- 2023-10-31T19:00:00+01:00
GDCh-Preisverleihung
Stefan Flesch, Universität Bonn Ultrafast dynamics of photochemical nitrile imine formation Claudia Gräve, Universität Bonn 2DIR Spectroscopy of Vibrational Energy Transfer and Vibrational Coupling Jun.-Prof. Dr. Patrycja Kielb, Universität Bonn Exploring heme-enzyme tunability with resonance Raman spectro-electrochemistry
- 2023-11-07T17:00:00+01:00
- 2023-11-07T18:00:00+01:00
GDCh-Kolloquium Prof. Dr. Oliver Reiser
Copper makes the difference: Developing Sustainable Photoredox Catalyzed Transformations Synthetic organic chemistry undertakes significant efforts to develop new catalytic transformations that utilize greener reagents and avoid stoichiometric additives. In this regard, visible-light photoredox catalysis offers a unique activation mode of molecules, which serves as an alternative to many thermal transition-metals catalyzed reactions. The vast majority of photoredox-catalyzed processes capitalizes on heavy metals, namely, Ru(II) or Ir(III)-complexes which can serve as single electron oxidants or reductants in their photoexcited states.
- 2023-11-14T10:00:00+01:00
- 2023-11-14T12:00:00+01:00
Prof. Laura Rodríguez Raurell, Universitat de Barcelona
Title and abstract to be announced Title and abstract to be announced
- 2023-11-28T17:00:00+01:00
- 2023-11-28T18:00:00+01:00
GDCh-Kolloquium Prof. Dr. Tsuyoshi Kato
Low-valent silicon complexes and their analogues: surprising and peculiar behaviors For over ten years, we have been developing the chemistry of low-value silicon complexes with a unique phosphine ligand system. These complexes exhibit special properties (somewhat like transition metals). When this ligand system is applied to synthesize other stable complexes of low-valent main-group elements, they also exhibit peculiar and surprising behaviors, allowing us to develop even more amusing chemistry. In my talk, I'll present some recent results on their chemistry.
- 2023-12-12T17:00:00+01:00
- 2023-12-12T18:00:00+01:00
GDCh-Kolloquium Prof. Dr. Carole Duboc
Bio-inspired catalysts for clean H<sub>2</sub> production Hydrogen production through water splitting emerges as a pertinent solution in the long run for renewable energy storage. Hydrogenases, which are organometallic enzymes containing iron and/or nickel metal centers, exhibit catalytic performances that rival platinum for hydrogen evolution. Their fascinating properties make them the ideal inspiration for designing molecular catalysts for technological devices. During this presentation, the bio-inspired strategy will be illustrated: How can this approach be at the origin of efficient systems that achieve H<sub>2</sub> production in a catalytic manner? How can it provide helpful information regarding the catalytic mechanism of the enzymes?