Karl Schlögl-Preis 2018

Saad Shaaban wird für seine Dissertation I. The keteniminium ion: A Convenient Synthetic Intermediate. II. Redox reactions: Metal-Free Redox Transformations for C-C and C-N Bond Construction ausgezeichnet.

The thesis is divided into two chapters. The first chapter studied the reactive intermediate ‘‘Keteniminium ion’’ that is usually generated in situ from amides or ynamides and has been successfully utilized in a range of reactions. The construction of pentasubstituted pyridines by means of a [2+2+2] cycloaddition reaction of activated ynamides and cyanoalkynes was successfully achieved. This method provided a metal-free approach for the synthesis of pyridine derivatives, a family of compounds that exists in a variety of natural products, pharmaceuticals and ligands for catalysis. Also, the α-arylation of activated amides with hydroxamic acids via [3,3] sigmatropic rearrangements was reported. Amides are perhaps the key chemical connection in life and are found in a plethora of organic molecules. This methodology provided a metal-free approach for direct C-C bond formation between simple amides and anilines in a regioselective manner.

In the second chapter a new redox reactions were developed. The use of hydrazine derivatives to promote the reduction of diazonium salts into the corresponding aryl radicals and engaging them in a variety of transformations for C-C bond formation was achieved. Hydrazines acted in dual role when used in stoichiometric quantities leading to the formation of 1,4 diamine moieties. Additionally, a visible light photo-catalyzed formation of bis-indole derivatives via 1,5 hydrogen migration was also accomplished.

Der Preisträger

Saad Shaaban hat das Bachelor-Studium im Fach Chemie 2008 an der Universität Damaskus absolviert und war an dieser Universität von 2008-2010 wissenschaftlicher Mitarbeiter an der Fakultät für Chemie. Das Masterstudium im Fach Chemie hat Saad Shaaban 2013 an der Ruhr Universität Bochum abgeschlossen. An der Universität Wien promovierte er 2018 im Fach Organische Chemie. Am Institut für Organische Chemie der Universität Wien ist Saad Shaaban seit 2013 als Laborassistent beschäftigt.