Name: Michael Hagemann
Diploma / M.Sc degree: Westfälische Wilhelms-Universität Münster, Germany
(May 2004)
Title: Compounds of Group 13 to 15 elements with Geminal Donor Functions


Homepage: www.uni-muenster.de/Chemie.ac/mitzel/welcome.html

Abstract of Research Project

Silicon compounds with donor atoms in geminal position show properties that differ very much from their carbon analogues. These differences include spectroscopic and structural properties as well as reactivity behaviour. The higher reactivity of β-donor substituted silanes in nucleophilic substitution reactions at the silicon atom has led to a multitude of applications for these systems as cross linking agents in the field of polymer silicon chemistry, and as adhesive auxiliaries.

The anomalous properties of geminal donor substituted silanes are commonly explained by an intermolecular coordination between the silicon atom and the donor function. This interaction was referred to as "α-effect". The coordination of main group metals and the nature of the α-effect are controversially discussed in the literature, but no appropriate theoretical model, that covers both structural and reactivity behaviour, could be established, yet.

My work will focus on the synthesis, reactivity studies and structure determination of geminal donor substituted silanes, their higher homologues and related compounds with group 15 acceptor centres. In addition to the experimental studies these systems will be analysed theoretically as well. Examinations of the electron density topology and orbital interactions will be performed and might help to describe the donor-acceptor interaction and the hypercoordination of main group elements in such geminal systems.



eMail: Michael Hagemann