October 11th, 2022 Webinar Speakers
Our next webinar will take place via the internet on Tuesday October 11th at 10 AM EDT/3 PM BST. 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 Violeta Vetsova (Graduate Student, Ludwig Maximilian University of Munich, Germany), and Dr Parul Verma (Postdoctoral Researcher, Jawaharlal Nehru Centre for Advanced Scientific Research, India).
LEARN MORE ABOUT THE SPEAKERS AND THEIR TALKS BELOW
Biography: Violeta was born and raised in Bulgaria, before moving to Germany to study chemistry at the Ludwig Maximilian University of Munich with emphasis of bioinorganic and organic chemistry. She prepared her bachelor thesis in the group of Prof. Paul Knochel, where she studied chromium(III)-catalyzed cross-coupling reactions. During her master’s studies, Violeta was an intern at Bayer in Wuppertal and later she joined the lab of Prof. Lena Daumann for her master’s thesis. After completing her studies, she stayed in the group as a PhD student and now she is working on designing model complexes for lanthanide(III) and calcium(II) dependent alcohol dehydrogenases.
Title of Talk: An Active Site Model for Lanthanide and Calcium Dependent Alcohol Dehydrogenases
Abstract: Since their discovery, lanthanides (Ln) were generally expected to be biologically inactive due to their low biological accessibility. However, in 2014 Pol et al. discovered that the methanotrophic bacterium Methylacidiphilum fumariolicum SolV is strictly Ln-dependent due to a XoxF-type methanol dehydrogenase (MDH), which contains a pyrroloquinoline quinone (PQQ) cofactor bound to a Ln(III) ion in its active site. For decades, it was assumed that most methanotrophic bacteria catalyse methanol oxidation solely by using the well-known calcium(II)-dependent MxaF-type MDH. With the discovery of the lanthanide(III)-dependent species however, the question of the evolutionary advantage of Ln over Ca arose.
With the perspective to study the coordination chemistry of Ln in alcohol dehydrogenases and to compare it with the one of Ca, we reported a PQQ-based biomimetic complex system capable of oxidizing a benzylic alcohol to the respective aldehyde. Investigations using NMR as well as mass spectrometry techniques allowed us to demonstrate the importance of charge and size of the complex cation, as well as counterions and base. Furthermore, an EPR analysis of the obtained complexes and reaction mixtures show the presence of quinone-based radicals.
DR PARUL VERMA (on Twitter @ParulVermaChem)
Biography: Parul was born in Varanasi in northern India. She obtained her BSc honours and MSc at the Institute of Science at Banaras Hindu University. Then she joined the Indian space research organisation to work on multifunctional coating on spacecraft alloys. Afterwards, she continued her academic career at Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR, India) by performing a Ph.D. on metal-organic hybrid 'Soft' Materials towards hydrogen production, carbon dioxide reduction, and optoelectronic applications. In July 2022, she joined the Ben Feringa research group at the University of Groningen as a postdoctoral researcher to work on bithioxanthenylidene based self-assembly for photocatalytic application.
Title of Talk: Visible Light Driven Photocatalytic CO2 Reduction to CO/CH4 using Metal-Organic ‘Soft’ Coordination Polymer Gel
Abstract: The self-assembly of well-defined and astutely designed, low molecular weight gelator (LMWG) based linker with a suitable metal ion is a promising method for preparing photocatalytically active coordination polymer gels. Here, we report the design, synthesis, and gelation behaviour of a tetrapodal LMWG based on a porphyrin core connected to four terpyridine units (TPY-POR) through amide linkages. The self-assembly of TPY-POR LMWG with RuII ions results in a Ru-TPY-POR coordination polymer gel (CPG), with a nanoscroll morphology. Ru-TPY-POR CPG exhibits efficient CO2 photoreduction to CO (3.5 mmol g-1 h-1) with >99% selectivity in the presence of triethylamine (TEA) as sacrificial electron donor. Interestingly, in the presence of 1-benzyl-1,4-dihydronicotinamide (BNAH) with TEA as the sacrificial electron donor, the 8e-/8H+ photoreduction of CO2 to CH4 is realized with >95 % selectivity (6.7 mmol g-1 h-1). In CPG, porphyrin acts as a photosensitizer and covalently attached [Ru(TPY)2]2+ acts as a catalytic center as demonstrated by femtosecond transient absorption (TA) spectroscopy. Further, combining information from the in situ DRIFT spectroscopy and DFT calculation, a possible reaction mechanism for CO2 reduction to CO and CH4 was outlined.