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Advanced Energetic Materials DISSERTATION ZUR ERLANGUNG DES DOKTORGRADES DER FAKULTÄT CHEMIE UND PHARMAZIE DER LUDWIG-MAXIMILIANS UNIVERSITÄT MÜNCHEN ADVANCED ENERGETIC MATERIALS: STRATEGIES AND COMPOUNDS DAVIN GLENN PIERCEY AUS RED DEER, KANADA 2012 Erklärung Diese Dissertation wurde im Sinne von § 7 der Promotionsordnung vom 28. November 2011 von Prof. Dr. Thomas M. Klapötke betreut. Eidesstattliche Versicherung Diese Dissertation wurde eigenständig und ohne unerlaubte Hilfsmittel erarbeitet. München, den 11.12.2012 ……………………………………….. (Davin Piercey) Dissertation eingereicht am: ....................................................... 1. Gutachter Prof. Dr. Thomas M. Klapötke 2. Gutachter Prof. Dr. Konstantin Karaghiosoff Mündliche Prüfung am ......................06.02.2013......... It is not death that a man should fear, but he should fear never beginning to live. -Marcus Aurelius Acknowledgements: Firstly, Prof. Dr. Thomas M. Klapötke must be thanked for the incredible experience the past three years have been. Not only for the opportunity to carry out my PhD work in your group, but also for the freedom to work on topics of my choice, for many calculations, conference travel, many useful discussion, and for going above and beyond helping me deal with German bureaucracy. Next I must thank Prof. Dr. Konstantin Karaghiosoff for countless enthusiastic late-night and weekend crystal structure measurements, for being there to discuss NMR results, and finally being the second corrector of this thesis. I would like to thank Dr. Jörg Stierstorfer for all the support provided; the solution of crystal structures and calculation of heats of formation and energetic performances would not have been possible without you. The whole research group, and especially my lab must be thanked for providing a great working environment becoming good friends, and the constant (if unsuccessful) reminders to speak German. Dennis Fischer, thank you for the endless chemical discussions, your enthusiasm and knowledge in all things explosive, and hilarious conversations about home chemistry. Niko Fischer, thank you for providing many precursor compounds, weisswurst eating competitions, and finding a place for me to live. Susanne Scheutzow thanks for assistance with time consuming detonation tests. “St.” Stefan Huber, thanks for the hundreds of sensitivity measurements and chemical orders. Richard Moll and Norbert Mayr, thanks for the extensive computer help. All of my Bachelor, F-praktikum, and Masters students are acknowledged for help in my research; Andi, Martin, Michael (“Hasi”), Flo, Angie, Franzi, Max, Jan, Chris, Stefanie, and Christin. Ms. Irene Scheckenbach is thanked for being a great secretary and helping me get settled when I first moved here. Everyone associated with LMU analytical services (NMR, mass spectrometry, elemental analyses) is thanked for their contributions. Everyone else who assisted with this work, or making my stay here pleasurable is also thanked. Finally and above all, my parents are extensively thanked for their continuous support in every aspect of my life, for believing in me, and for tolerating my basement lab and chemistry experiments for years. My father is especially thanked for telling tales of blackpowder and firecrackers to me as a child likely sparking this lifelong interest in energetic materials. Table of Contents 1. Introduction 1.1 History of Explosives………………………………………………….................1 1.2 Backgroundand Definitions…………………………………………...................3 1.3 Considerations in the Development of Modern Explosives……………...............6 1.4 Strategies in Energetic Materials Design………………………………..........…11 1.5 References……………………………………………………………............….19 1.6 Bibliography and Disclosure………………………………………............…….21 2- 2. Synthesis and Characterization of Energetic Salts of the C4N12 Dianion.......................24 3. Copper Salts of Halo Tetrazoles: Laser-Ignitable Primary Explosives..............................32 4. Method for Preparation of a Lead-Free Primary Explosive...............................................47 5. Improved Preparation of Sodium Nitrotetrazolate Dihydrate: Suitable for DBX-1 Preparation...............................................................................................................................56 6. Amination of Energetic Anions: High-Performing Energetic Materials ...........................60 7. The 1,3-Diamino-1,2,3-Triazolium Cation: A Highly Energetic Moiety...........................69 + 8. The 1,4,5-Triaminotetrazolium Cation (CN7H6 ): A Highly Nitrogen-Rich Moiety.........78 9. 1,1’-Azobis(tetrazole): A Highly Energetic Nitrogen-Rich Compound with a N10 Chain........................................................................................................................................85 9.1 Supporting Information..........................................................................................88 10. The 1,3-Bis(nitroimido)-1,2,3-triazolate Anion, the N-Nitroimide Moiety, and the Strategy of Alternating Positive and Negative Charges in the Design of Energetic Materials...................................................................................................................................98 11. The Synthesis and Energetic Properties of 5,7-Dinitrobenzo-1,2,3,4-tetrazine-1,3-dioxide (DNBTDO).............................................................................................................................108 12. Hydroxylammonium 5-Nitriminotetrazolates ................................................................117 13. Nitrotetrazolate-2N-Oxides and the Strategy of N-Oxide Introduction.........................126 13.1 Supporting Info...................................................................................................137 13.2 Addition/Correction............................................................................................144 14. Synthesis and Characterization of Alkaline and Alkaline Earth Salts of the Nitrotetrazolate-2N-oxide Anion............................................................................................145 - 15. The Taming of CN7 : The Azidotetrazolate-2-Oxide Anion...........................................152 16. A Study of Cyanotetrazole Oxides and Derivatives Thereof..........................................162 17. Pushing the Limits of Energetic Performance – The Synthesis and Characterization of Dihydroxylammonium 5,5’-Bistetrazolate-1,1’-diolate.........................................................174 17.1 Supporting Information......................................................................................179 18. The Facile Synthesis and Energetic Properties of an Energetic Furoxan Lacking Traditional “Explosophore” Moieties: (E,E)-3,4-bis(oximomethyl)furoxan (DPX1)...........198 19. Curriculum Vitae.............................................................................................................206 1/211 1. Introduction: 1.1 History of Explosives Around 220 BC Chinese alchemists were attempting to separate gold from silver via extraction from the ore with potassium nitrate and sulfur in a furnace, however they neglected to add charcoal early in the process and tried to make up for it later. The heated mixture of potassium nitrate, sulfur, and charcoal, the mixture currently known as black powder, albeit in differing proportions, proceeded to explode. Despite the initial lack of exploitation, this marked the first known instance of humanity’s experience with explosives. Knowledge of blackpowder in Western Europe was a considerably later, when the first description was by the monk, Roger Bacon, in England in 1249 AD. Between these times, there is mention of the use of black powder, and mixtures assumed to be black powder, for exploding war devices and fireworks by the Romans, Greeks, and Arabs between the 4th and 9th century. In 14th century Europe, the first crude firearm was described by a German monk, Berthold Schwarz; an iron tube capable of throwing stones, while the broad adoption of firearms in warfare took until the end of the 15th century, by which time crude grenades had also been invented. The composition of black powder was inconsistent across time and location until the 16th century when the composition stabilized, similar to the mix of today, at a 75:15:10 mixture of KNO3 : Charcoal : Sulfur. Further developments were solely in the realm of processing techniques such as corning and pressing, and modification of charcoal types. The use of black powder in mining for blasting can be traced to 1627 by the Hungarian engineer Kaspar Weindl near the town of Selmeczbanya, and was introduced to England in 1670.1,2 While the earliest development in explosives chemistry, blackpowder, found practical use in large quantities, the next significant discovery, that of fulminating gold,3 from dissolving gold oxide in ammonia, possessed such high sensitivity that it never found significant practical use. The German alchemist Sebald Schwaertzer mentions it in 1585 and this marks the discovery of the world’s first high explosive (blackpowder is a low explosive and these distinctions will be explained further in the next section). Despite fulminating gold being known in the 16th century, its nature was not understood until the present, and even now the best description is that it is a mixture of polymeric compounds, incapable of being represented by a simple formula, where the partial hydrolysis of [Au2(μ-NH2)(μ3-NH)2]Cl 4 is closest to reality. Mercury fulminate (Hg(CNO)2) followed
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