New Route to Synthesize Surface Organometallic Complexes (SOMC): An Approach by Alkylating Halogenated Surface Organometallic Fragments. Dissertation by Ali Hamieh In Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy King Abdullah University of Science and Technology Thuwal, Kingdom of Saudi Arabia February, 2017 2 EXAMINATION COMMITTEE PAGE The dissertation of Ali Hamieh is approved by the examination committee. Committee Chairperson: Professor Jean-Marie Basset Committee Members: Professor Kazuhiro Takanabe, Professor Udo Schwingenschlogl, Professor Joumana Toufaily. 3 © February, 2017 Ali Hamieh All Rights Reserved 4 ABSTRACT New Route to Synthesize Surface Organometallic Complexes (SOMC): An Approach by Alkylating Halogenated Surface Organometallic Fragments. Ali I. Hamieh The aim of this thesis is to explore new simpler and efficient routes for the preparation of surface organometallic complexes (SOMC) for the transformation of small organic molecules to valuable products. The key element in this new route relies on surface alkylation of various halogenated surface coordination complexes or organometallic fragments (SOMF). The first chapter provides an overview on the origin of organometallic compounds, their classical synthesis, characterization and some of their applications In the second chapter, novel silica-supported tungsten oxo-trimethyl complex [(≡Si-O- )W(=O)Me3] was synthesized using the new SOMC synthetic approach. WOCl4 was grafted on the surface of silica, partially dehydroxylated at 700°C (SiO2-700), and [(≡Si-O- )W(=O)Cl3] was produced. The supported complex methylated with ZnMe2 and transformed into [(≡Si-O-)W(=O)Me3], which was fully characterized. It was found that complex [(≡Si-O-)W(=O)Me3] has two conformational isomers at room temperature. This complex was found to be active in cyclooctane metathesis and direct transformation of ethylene to propylene. The third chapter elaborates the effect of substituents on catalysis. In this chapter we Dipp replace one methyl from [(≡Si-O-)W(=O)Me3] by a bulkier ligand (Im = 1,3-bis(2,6- diisopropylphenyl)imidazolin-2-iminato). Synthesis, structure, and olefin metathesis 5 Dipp activity of complex [(≡Si-O-)W(=O)(CH3)2-Im N] is reported. This complex proved to be an active pre-catalyst for self-metathesis of terminal olefins such as propylene and 1- hexene, showing better selectivity as compared to [(≡Si-O-)W(=O)Me3]. In the fourth chapter, surface alkylation strategy was used as a scalable method to synthesize the highly important complex [(≡Si–O−)WMe5] that obtained by in situ alkylation of the surface-grafted tungsten chloride [(≡Si–O−)WCl5] (1). Upon alkylation, a mixture of [(≡Si–O−)WMe5] and [(≡Si–O−)WMe2(≡CH)] was identified. The latter might have been generated by partial decomposition of the tungsten methyl chloride compound; this was confirmed by DFT calculations and experimental results. v In the fifth chapter, we isolated the first tetramethyl niobium complex [(≡SiO)Nb Me4] v (2) through the surface alkylation of [(≡SiO-)Nb Cl3Me] (1). Complex (1) was found to be active in the ethylene oligomerization by producing olefins up to C30, while surprisingly (2) selectively dimerizes ethylene into 1-butene and in both cases reaction occurs in the absence of any co-catalyst. 6 ACKNOWLEDGEMENTS I would like to extend thanks to the many people, who so generously contributed to the work presented in this thesis. Special mention goes to my great supervisor, Professor Jean-Marie Basset. I am highly honored and delighted to be his student. My PhD has been an amazing experience and I thank Professor Basset wholeheartedly, not only for his tremendous academic support, but also for giving me so many wonderful opportunities. Greatest gratitude to my committee members Professor Kazuhiro Takanabe, Professor Udo Schwingenschlogl and Professor Joumana Toufaily. So many people I need to thank especially Dr Manoja Samantaray, Dr Raju Dey, Dr Yin Chen, Dr. Ziyauddin Qureshi, Professor Valerio D’Elia, Dr Jérémie Pelletier and Dr. Santosh Kavitake. I thank them for the knowledge they share with me. I need to thank Dr. Edy Abou-Hamad for his contribution in lot of solid-state NMR experiments and for teaching me so many techniques. Special mention to Dr Youssef Saih for his fantastic training on dynamic flow catalytic reactions using PID reactors. I would like to thank Dr Safwat Abdellatif and Professor Luigi Cavallo for their contribution in the DFT calculations we perform. Finally, special mention goes to my friends Dr. Bilel Hamzaoui, Dr. Walid Almaksoud, Baraa Werghi, Reem Alshareef, Dr. Kushal Bhatte, Dr Samir Barman, Dr Niladri Maity, Dr. Janet Mohandas, Dr. Umesh Patil, Dr. Eva Pump, Dr. Anissa BendjeriouSedjerari, Gabriel Jeantelot, Dr. Michael J. Kelly, Dr. Jullian Vittenet, Dr. Serena Goh, Dr. Jeff Espinas and Dr.Julien SofackKreutzer., 7 DEDICATION To the biggest contributors since I opened my eyes to this world, to Mom and Dad. To the lady who I loved the most, my wife Rowaida and to the God’s gift for us, our son Hassan. To my special uncle Haj Mohammad Hamieh, I will always remember your advices, wisdom, and your white hands. To my family and all the beloved ones… 8 TABLE OF CONTENTS EXAMINATION COMMITTEE PAGE ......................................................................................... 2 ABSTRACT ............................................................................................................................. 4 DEDICATION .......................................................................................................................... 7 TABLE OF CONTENTS ............................................................................................................. 8 LIST OF ABBREVIATIONS ...................................................................................................... 12 LIST OF SYMBOLS ................................................................................................................ 13 LIST OF ILLUSTRATIONS ....................................................................................................... 14 LIST OF SCHEMES................................................................................................................. 19 LIST OF TABLES .................................................................................................................... 21 CHAPTER 1: Bibliography ..................................................................................................... 23 Introduction................................................................................................................... 24 1.1. Overview on Catalysts ............................................................................................ 24 1.2. Two main Types of catalysts: ................................................................................. 25 1.2.1. Homogeneous Catalysis ................................................................................... 25 1.2.2. Heterogeneous Catalysis ................................................................................. 25 1.3. Heterogeneous vs. Homogenous Catalysis ............................................................ 25 1.4. Bridging the gap by SOMC ...................................................................................... 26 1.5. History of SOMC ..................................................................................................... 27 1.6. SOMC complexes .................................................................................................... 27 1.6.1. Support ............................................................................................................ 28 1.6.2. Grafted Metals ................................................................................................. 30 1.6.3. Functional and spectator ligands .................................................................... 30 1.7. Grafting a complex ................................................................................................. 30 1.7.1 Reaction of Metal-Alkyl Complexes .................................................................. 30 1.7.2. Reactivity of Metal Alkoxide ............................................................................ 32 1.7.3. Reactivity of Metal halide ................................................................................ 33 1.8. Characterization ..................................................................................................... 33 9 1.9. Some Applications of SOMC based complexes ...................................................... 34 1.9.1. Metathesis of alkane ....................................................................................... 34 1.9.2. Conversion of ethylene into propylene ........................................................... 34 1.9.3. Olefin metathesis ............................................................................................. 36 1.10. Transition metal alkylation ................................................................................... 37 1.10.1. Alkylating agents rise ..................................................................................... 37 1.10.2. Importance of organometallic compounds ................................................... 37 1.10.3. Early transition metals coordinated to methyl ligands ................................. 38 1.10.4. Early transition metals coordinated to neopentyl ligands ...........................