Homochiral Crystals for Selective Synthesis
Six new coordination compounds were prepared from monodentate sulfide ligands and copper(I) halides and their crystal structures were determined by single-crystal X-ray diffraction. The aim was to prepare coordination polymers that crystallize as conglomerates in order to use them in total spontaneous resolution. The anionic and neutral ligands were varied in order to examine how they would affect the crystallization. All six complexes formed racemic crystals, and five of them were polymeric. Bidentate sulfide ligands were used to increase the possibility of obtaining a coordination polymer. Five new complexes were prepared and structurally characterized by single crystal X-ray diffraction. Three of the complexes formed coordination polymers but none of them crystallized as a conglomerate. Tetrahedral metal complexes have been resolved by total spontaneous resolution for the first time. A cationic silver(I) complex with a bidentate sulfide ligand was prepared and it crystallized as a conglomerate. Enantioenriched crystal batches were obtained with enantiomeric excesses up to 90 %. Three chiral Ru(II) complexes with bidentate sulfide ligands were prepared and all three crystallized as conglomerates. They were used in absolute asymmetric synthesis and oxidized enantioselectively. The oxidations resulted in a selectivity of > 98% without the use of a chiral catalyst. One of the Ru(II) complexes isomerizes when exposed to light. Four new phases, containing one or both isomers, co-crystallized from the same solution.
Parts of work
I. Towards absolute asymmetric synthesis of coordination polymers with prochiral substrates Theonitsa Kokoli and Mikael Håkansson, Submitted to CrystEngCommII. Towards absolute asymmetric synthesis of coordination polymers with bidentate sulfide ligands Theonitsa Kokoli, Susanne Olsson, Per Martin Björemark, Staffan Persson, and Mikael Håkansson, Submitted to J. Organomet. Chem.III. Total Spontaneous Resolution of Tetrahedral Complexes Theonitsa Kokoli and Mikael Håkansson, Submitted to Angew. Chem. Int. Ed.IV. Absolute Asymmetric Synthesis: Protected Substrate Oxidation Theonitsa Kokoli, Susanne Olsson, Per Martin Björemark, Jonas Sundberg, Anders Lennartson, Christine J. McKenzie, and Mikael Håkansson, Submitted to Angew. Chem. Int. Ed.V. Concomitant Polymorphism and Co-crystallization of Diastereomers Theonitsa Kokoli and Mikael Håkansson, Submitted to Chem. Eur. J.
Doctor of Philosophy
University of Gothenburg. Faculty of Science
Department of Chemistry ; Institutionen för kemi
Fredagen den 6 maj 2011, kl. 13.15, sal KA, Götebors universitet o Chalmers tekniska högskola
Date of defence
Absolute asymmetric synthesis
total spontaneous resolution
single crystal X-ray crystallography
enantioselective sulfide oxidation
co-crystallization of diastereomers