- Dispersion Effects on Reactivity and Chemo-, Regio- and Stereoselectivity in Organocatalysed Domino Reactions: A Joint Experimental and Theoretical Study
(Third Party Funds Group – Sub project)Overall project: SPP 1807: Control of London dispersion interactions in molecular chemistry
Term: Jan 1, 2015 - Jan 1, 2018
Funding source: DFG / Schwerpunktprogramm (SPP)
URL: http://www.uni-giessen.de/fbz/fb08/dispersionThis joint experimental and theoretical project aims at the development of facile and environmentally friendly organocatalytic multi-step domino reactions exploiting dispersion interactions in these novel systems. We plan to conduct a series of multi-component domino reactions involving readily available nitroolefins and aldehydes, as well as CH-acidic malononitrile already known for its broad application and its versatile use as an exceptionally reactive compound. We will mainly focus on the following three unprecedented reactions: (i) three-component two-step domino Knoevenagel/vinylogous Michael reaction; (ii) three-component five-step branched domino Knoevenagel/nitro-Michael/nitroalkane-Michael/intramolecular condensation/isomerization; (iii) two-component six-step domino Knoevenagel/dimerisation/ intermolecular condensation/intramolecular aza-Michael/intramolecular condensation/ isomerization reaction. Detailed mechanistic investigations will be performed using conventional density-functional methods in conjunction with semiempirical van der Waals corrections as well as novel highly accurate density-functional methods to shed light on the intriguing differences in chemoselectivity, regioselectivity and stereoselectivity in these organocatalysed domino transformations, and, in particular, to understand and exploit the influence of dispersion interaction in these transformations. Taking the envisioned domino reactions as test cases, computational setups for a density-functional based description of organocatalysis will be developed.
(Third Party Funds Group – Sub project)Overall project: FOR 1878: funCOS - Functional Molecular Structures on Complex Oxide Surfaces
Term: Aug 1, 2013 - Aug 1, 2016
Funding source: DFG - Forschergruppen
With the help of electronic structure calculations, the project aims at a comprehensive theoretical understanding at the microscopic level of the adsorbate-substrate and adsorbate-adsorbate interactions of functionalized organic molecules on structured oxide surfaces, which eventually shall enable a controlled formation of organic films with specific structural, electronic and optical properties. The first basic interaction, the adsorbate-substrate interaction, is the bonding of organic molecules to pristine oxide surfaces or to low-coordinated sites on structured oxide substrates and the variation of this binding by different linker groups that modify the bonding geometry and strength, which, subsequently, may influence the second important interaction, the adsorbate-adsorbate interaction, as well as the diffusion kinetics and structure formation. The different interactions shall be calculated and analyzed with density-functional methods supplemented by Van-der-Waals corrections and, where necessary, by Hubbard-U approaches. For the investigation of structure formation also semi-empirical methods shall be employed, which enable the treatment of large molecular assemblies on structured oxide surfaces. Adsorbed organic molecules may show new photo-physical and electronic properties originating from the interaction of their frontier states with the substrate electronic structure. Another aim of the project is to analyze and understand these modifications of the molecules and to unravel possible charge transfer processes between the adsorbate and the substrate that are pivotal for applications encompassing photovoltaics, sensing, illumination, and photo-chemistry. To that end, based on density-functional calculations, time-dependent density-functional methods and many-body perturbation-theory methods shall be applied.
- Quantenchemische Untersuchungen zu Bildung, Struktur, Energie und elektronischen Eigenschaften von Carbinen, Fullerenen und Graphenen (C02)
(Third Party Funds Group – Sub project)Overall project: SFB 953: Synthetic Carbon Allotropes
Term: Jan 1, 2012 - Jan 1, 2015
Funding source: DFG / Sonderforschungsbereich (SFB)
URL: https://www.chemistry.nat.fau.eu/research/dfg/sfb953/Im Projekt sollen Kohlenstoffmaterialien, Fullerene, Polyine, Graphene wie auch bisher noch nicht synthetisierte Kohlenstoffallotrope wie beispielsweise Graphyne mit nichtempirischen elektronischen Strukturmethoden insbesondere etablierten wie neu zu entwickelnden Dichtefunktionalmethoden untersucht werden. Mit dem Ziel neue Kohlenstoffverbindungen und -materialien herzustellen sollen deren Bildung, Struktur und Energetik wie auch ihre spektroskopischen und elektronischen Eigenschaften analysiert und vorhergesagt werden.