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Sharanappa Nembenna Sharanappa Nembenna ____________________________________________________________ β−Diketiminate Ligand Supported Group 2 Metal Hydroxide, Halide, Oxygen Bridged Heterobimetallic and Heterotrimetallic Complexes: Synthesis and X-ray Structural Studies Göttingen 2007 β−Diketiminate Ligand Supported Group 2 Metal Hydroxide, Halide, Oxygen Bridged Heterobimetallic and Heterotrimetallic Complexes: Synthesis and X-ray Structural Studies Dissertation zur Erlangung des Doktorgrades der Mathematisch-Naturwissenschaftlichen Fakultäten der Georg-August-Universität zu Göttingen Vorgelegt von Sharanappa Nembenna Aus Kallur (INDIA) Göttingen 2007 D 7 Referent: Prof. Dr. Dr. h. c. mult. Herbert W. Roesky Korreferent: Prof. Dr. Dietmar Stalke Tag der mündlichen Prüfung: 30.10.2007 Dedicated to my mother Channabasamma and My eldest brother late Mallikarjungouda Acknowledgement The work described in this doctoral thesis has been carried out under the guidance and supervision of Prof. Dr. Dr. h. c. mult. Herbert W. Roesky at the Institut für Anorganische Chemie der Georg-August-Universität in Göttingen between April 2004 and September 2007. My grateful thanks to Prof. Dr. Dr. h. c. mult. Herbert W. Roesky for his constant advice, guidance, motivation, suggestions, and discussions throughout this work. I would like to thank him for his personal attention and the freedom I enjoyed during my stay in Göttingen. I would like to thank Prof. G. M. Sheldrick, Prof. D. Stalke, Prof. J. Magull, Dr. M. Noltemeyer, Mr. H. Ott, Ms. A. Hofmeister, Mr. A. Pal, and Mr. H.-G. Schmidt for their kind help in X-ray crystallographic studies. I thank Dr. R. B. Oswald for the theoretical studies. And also I thank Dr. P.-J. Wilbrandt, Mr. M. Hahn, Ms. U. Bethe, for the SEM and EDX analyses. I express my sincere thanks to Prof. Dr. N. S. Hosmane, Northern Illinois University, Dekalb USA and Prof. Dr. K. V. Katti, Missouri Columbia USA for their encouragement and sharing their ideas with me during their stay in Göttingen. I could not have finished my research work without the help from technical and non technical staff from our institute. I thank Mr. W. Zolke, Mr. J. Schöne, Dr. G. Elter, Dr. M. John (NMR studies), Dr. D. Böhler, Mr. T. Schuchhardt (mass spectral measurements), Mr. M. Hesse (IR spectral measurements), Mr. M. Schlote, and the staff of analytical division for their timely help. I am also thankful to all the members of glass blowing section, work shop, chemical store as well the security of our institute for their co-operation and help in all kind of situations. I wish to offer my sincere thanks to the members of our group starting with ex-members, Dr. S. K. Pandey, Dr. S. Singh, Dr. U. N. Nehete, Dr. L. Pineda, Dr. H. Zhu, Dr. J. Chai, Dr. S. Shravankumar, Dr. V. Jancik, Dr. S. K. Mandal, Dr. V. M. Jimenez-Perez, Dr. Y. Zhi, Mr. T. Blunk, Mr. C. Ene, and the present members Dr. S. Nagendran, Mr. P. M. Gurubasvaraj, Mr. Y. Ying, Dr. G. Nikiforov, Dr. D. Ghoshal, Mr. Z. Zhang, Mr. S. Sarish, Mr. B. Nekouei, Mr. S. S. Sen, and Mr. A. Jana, for their cooperation and help during the course of this work. Especially I would like to thank Dr. S. Singh, Dr. U. N. Nehete for their help to start my research in our lab and in learning new lab techniques. And also my special thanks to Dr. S. Nagendran and Dr. K. Starke for their support and kind help. I am also greatly indebted to many teachers in the past and present, starting from school education till the completion of the studies in the university. I am greatly thankful to all my family members especially, my mother and my brothers, Mr. Mayashankaragouda, Mr. Gundappagouda, Mr. Amarappagouda, and relatives, specially my brother-in-law Mr. B. Nagabhushanagouda, and my close friend Dr. V. V. Sanjeevkumar, for their motivation and support in accomplishing this work. The financial support from the Göttinger Akademie der Wissenschaften and the Deutsche Forschungsgemeinschaft (DFG) is gratefully acknowledged. I will be always indebt to this Georg-August-Universität, Göttingen, and beautiful city of Göttingen, for obtaining my Ph.D. and making my stay here peaceful and happy. I bow down in front of THE ALMIGHTY GOD for providing me the health, strength, and this opportunity in my life. Table of Contents Table of Contents 1. Introduction ................................................................................................................................1 1.1. β-Diketiminate ligands .........................................................................................................1 1.2. β−Diketiminate supported group 2 metal hydroxides ..........................................................3 1.3. β−Diketiminate supported group 2 metal halides..................................................................5 1.4. Heterobi- and trimetallic oxygen bridged complexes ...........................................................7 1.5. Heterobi- and trimetallic compounds with the Mg–O–Al structural motif...........................8 1.6. Heterometallic oxides containing calcium ............................................................................9 1.7. Alkaline earth metal-zirconium oxide compounds ...............................................................9 1.8. Aluminum-tin oxide complexes ..........................................................................................10 1.9. Heterotrimetallic oxygen bridged system with three different metal atoms .......................11 1.10. Aim and scope of the present work...................................................................................11 2. Results and Discussion .............................................................................................................13 2.1. Hydrolysis of LMgN(SiMe3)2 and X-ray crystal structure of [LMg(OH)·THF]2 (1) .........13 2.2. Hydrolysis of LCaN(SiMe3)2·THF and X-ray crystal structure of [LCa(OH)·THF]2 (2) .15 2.3. Reaction of LIH with MeMgCl and X-ray crystal structure of [LIMg(Cl)] (3)...................18 2.4. Reaction of LCaN(SiMe3)2·THF with Me3SnF and X-ray crystal structure of [LCa(F)·THF]2 (4) ..............................................................................................................20 2.5. The application of soluble calcium derivatives for surface coating....................................23 2.6. Reaction of LAl(Me)OH with Mg{N(SiMe3)2}2 and X-ray crystal structure of [L(Me)Al– O–Mg(THF)2–N(SiMe3)2] (5) ............................................................................................26 2.7. Reaction of LAl(Me)OH (2 eqv) with Mg{N(SiMe3)2}2 and X-ray crystal structure of [L(Me)Al–O–Mg(THF)2–O–Al(Me)L] (6)........................................................................29 2.8. Reaction of LAl(Me)OH with LMgMe·OEt2 or LMgN(SiMe3)2 and X-ray crystal structure of [LMg(THF)–O–Al(Me)L] (7·THF)...............................................................................31 2.9. Reaction of LAl(Me)OH with Ca{N(SiMe3)2}2·2THF and X-ray crystal structure of II [{L Al(Me)}(μ-O)(Ca·THF)]2 (8)......................................................................................33 2.10. Reaction of LAl(Me)OH with LCaN(SiMe3)2·THF..........................................................38 2.11. Reaction of Cp*2Zr(Me)OH (2 eqv) with Mg{N(SiMe3)2}2 and X-ray crystal structure of [Cp*2(Me)Zr–O–Mg(THF)2–O–Zr(Me)Cp*2] (10) ...........................................................39 2.12. Reaction of Cp*2Zr(Me)OH with Ca{N(SiMe3)2}2·2THF and X-ray crystal structure of [Cp*2(Me)Zr–O–Ca(THF)3N(SiMe3)2] (11) ......................................................................41 i Table of Contents 2.13. Reaction of [L(Me)Al–O–Mg(THF)2–N(SiMe3)2] (5 ) with Ph3SnOH and X-ray crystal structure of [L(Me)Al–O–SnPh3] (12) ...............................................................................43 2.14. Reaction of LAl(Me)OH with (2 eqv) Sn{N(SiMe3)}2 and X-ray crystal structure of [L(Me)Al–O–Sn–O–Al(Me)L] (13)...................................................................................45 2.15. Reaction of [L(Me)Al–O–Mg(THF)2–N(SiMe3)2] (5) with LAl(Me)OH and X-ray crystal structure of [L(Me)Al–O–Mg(THF)2–O–Zr(Me)Cp*2] (14)..................................48 3. Summary and Future Directions ............................................................................................51 4. Experimental Section ...............................................................................................................57 4.1. General procedures..............................................................................................................57 4.2. Physical measurements........................................................................................................57 4.3. Starting materials.................................................................................................................58 4.4. Syntheses of compounds 1-14.............................................................................................59 4.4.1. Synthesis of [LMg(OH)·THF]2 (1)...............................................................................59 4.4.2. Synthesis of [LCa(OH)·THF]2 (2)...............................................................................59 4.4.3. Synthesis of [LIMg(Cl)] (3).........................................................................................60 4.4.4. Synthesis of [LCa(F)·THF]2 (4) ..................................................................................61 4.4.5. Synthesis of [L(Me)Al–O–Mg(THF)2–N(SiMe3)2]
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