University of Groningen Magnesium and zinc hydride complexes Intemann, Julia IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below. Document Version Publisher's PDF, also known as Version of record Publication date: 2014 Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Intemann, J. (2014). Magnesium and zinc hydride complexes: From fundamental investigations to potential applications in hydrogen storage and catalysis. [S.n.]. Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons). The publication may also be distributed here under the terms of Article 25fa of the Dutch Copyright Act, indicated by the “Taverne” license. 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Download date: 07-10-2021 Magnesium and Zinc Hydride Complexes From Fundamental Investigations to Potential Applications in Hydrogen Storage and Catalysis Julia Intemann The work described in this thesis was performed at the Faculty for Chemistry at the University of Duisburg-Essen, Germany, the Stratingh Institute for Chemistry at the University of Groningen, The Netherlands and at the Department of Chemistry and Pharmacy at the Friedrich-Alexander University Erlangen-Nürnberg, Germany. Part of this research was performed within the framework of the DFG project: Metall- Amidoborane als Wasserstoffspeicher: Untersuchungen aus metallorganischer Sicht. The authors gratefully acknowledge the support of the University of Groningen, the Deutsche Forschungsgemeinschaft and the Friedrich-Alexander university of Erlangen- Nürnberg. Cover design by Julia Intemann. Printed by: Ipskamp Drukkers BV, Enschede, The Netherlands. Magnesium and Zinc Hydride Complexes From Fundamental Investigations to Potential Applications in Hydrogen Storage and Catalysis PhD thesis to obtain the degree of PhD at the University of Groningen on the authority of the Rector Magnificus, Prof. E. Sterken and in accordance with the decision by the College of Deans. This thesis will be defended in public on Friday 14 February 2014 at 14:30 hrs. by Julia Intemann born on 25 November 1983 in Achim, Germany Supervisor: Prof. S. Harder Assessment committee: Prof. S. Schulz Prof. A.J. Minnaard Prof. T.T.M. Palstra ISBN: 978-90-367-6744-6 (print) 978-90-367-6745-3 (electronic) You have brains in your head. You have feet in your shoes. You can steer yourself any direction you choose. Dr. Seuss Meinen Eltern: Marion & Holger Contents Chapter 1 Introduction ................................................................................................ 1 1.1. Magnesium and zinc in comparison .................................................................. 2 1.1.1. Magnesium ................................................................................................ 2 1.1.2. Zinc ............................................................................................................ 3 1.1.3. Direct comparison ...................................................................................... 4 1.2. Metal hydrides ................................................................................................... 7 1.2.1. Hydrogen ................................................................................................... 7 1.2.2. Metal hydride salts ..................................................................................... 7 1.2.3. Metal hydride complexes ........................................................................... 8 1.3. Hydrogen storage ........................................................................................... 11 1.4. References ...................................................................................................... 16 Chapter 2 Magnesium hydride clusters .................................................................... 21 2.1. Introduction ..................................................................................................... 22 2.2. Goal ................................................................................................................ 27 2.3. Results and Discussion ................................................................................... 28 2.3.1. Decomposition studies ............................................................................. 28 2.3.2. Insights into stability and decomposition by deuterium labeling .............. 39 2.3.3. Theoretical studies ................................................................................... 45 2.4. Conclusions and future perspective ................................................................ 55 2.5. Experimental ................................................................................................... 57 2.5.1. General .................................................................................................... 57 2.5.2. NN-(MgH)2 in THF ................................................................................... 57 2.5.3. Thermal decomposition of Mg hydride complexes .................................. 58 2.5.4. Synthesis of the complexes ..................................................................... 59 2.5.5. Reduction of halides and hydrides ........................................................... 61 2.5.6. Deuterium-labeling studies ...................................................................... 62 2.5.7. Computational Details .............................................................................. 65 2.6. References ...................................................................................................... 66 Chapter 3 Zinc hydride clusters ................................................................................ 69 3.1. Introduction ..................................................................................................... 70 3.2. Goal ................................................................................................................ 73 3.3. Results and Discussion ................................................................................... 74 I 3.3.1. Synthesis of zinc hydride clusters ........................................................... 74 3.3.2. Decomposition studies ............................................................................ 84 3.3.3. Theoretical studies .................................................................................. 91 3.3.4. Ligand screening and design of new ß-diketiminate ligands ................... 96 3.4. Conclusions and future perspective .............................................................. 103 3.5. Experimental ................................................................................................. 105 3.5.1. General .................................................................................................. 105 3.5.2. Synthesis of complexes ......................................................................... 105 3.5.3. Decomposition ....................................................................................... 109 3.5.4. BODDI ligands for Zn complexes .......................................................... 109 3.5.5. Ligand design for metal hydride clusters ............................................... 113 3.5.6. Computational Details ........................................................................... 117 3.5.7. Crystal structure determinations ............................................................ 117 3.6. References ................................................................................................... 121 Chapter 4 Reactivity studies ................................................................................... 125 4.1. Introduction ................................................................................................... 126 4.2. Goal .............................................................................................................. 130 4.3. Results and discussion ................................................................................. 131 4.3.1. Magnesium hydride complexes ............................................................. 131 4.3.2. Zinc hydride complexes ......................................................................... 141 4.3.3. Calcium hydride complexes ................................................................... 144 4.3.4. Catalysis with calcium hydride complexes – Hydrosilylation ................. 147 4.3.5. Catalysis with magnesium hydride complexes – Hydroboration ........... 153 4.4. Conclusions .................................................................................................. 160 4.5. Experimental section ...................................................................................