Heterocyclic Salt Synthesis and Rational Properties Tailoring

• Autorzy: Shackelford S. A. , Belletire J. L.
• Języki publikacji: EN

Abstrakty

EN

Chemical structure determines the inherent properties displayed by a given compound, and these properties, in turn, produce a specifc performance behavior. Rationally designing chemical structure to predictably modify compound properties, such that performance behavior can be tailored in a controlled manner, defnes the objective of a pertinent synthesis effort. Achieving this objective by introducing structural alterations in a neutral covalent compound offers only one approach for resultant properties modifcation. Heterocyclic salts signifcantly enhance the fexibility for achieving properties modifcation via three strategic approaches: (1) compositionally pairing various cation structural classes with a number of anion structural classes, (2) systematically altering the structure of the cation; and, (3) systematically altering the structure of the anion. To illustrate this premise, four general synthesis methods to synthesize heterocyclic salts, including several new binary heterocyclium icosahedral closo-borane and closo- carborane salts, frst are outlined. Secondly, properties modifcation approaches of neutral covalent compounds are then compared with those approaches available for various heterocyclic salts. Lastly, a key example, using three unsaturated bridged heterocyclium di-cation salts, demonstrates how rational structure design, and its effect on resultant predictable properties modifcation, produces tailored performance behavior to reach the thermochemical initiation threshold needed for combustion. This is achieved with predictable properties modifcations that increase salt energy content, or that accelerate the reaction kinetics of the thermochemical initiation process.

Słowa kluczowe

EN

binary heterocyclic salts; heterocyclic salt synthesis; ionic liquids; bridged heterocyclic di-cation salts; rational structure design; predictive properties modification; tailored performance behavior; thermochemical

• Wydawca: Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
• Czasopismo: Central European Journal of Energetic Materials
• Rocznik: 2009
• Tom: Vol. 6, nr 3-4
• Strony: 219--237
• Opis fizyczny: Bibliogr. 9 poz.

Twórcy

autor

Shackelford S. A.

autor

Belletire J. L.

• Air Force Research Laboratory, 10 East Saturn Blvd., Edwards AFB, CA 93524-7680, USA,

Bibliografia

• [1] Wilkes J.S., Levisky J.A., Wilson R.A., Hussey C.L., Dialkylimidazolium Chloroaluminate Melts: A New Class of Room-Temperature Ionic Liquids for Electrochemistry, Spectroscopy, and Synthesis, Inorg. Chem., 1982, 21, 1263-1264.
• [2] Drake G., Hawkins T., Brand A., Hall L., McKay M., Vij A., Ismail I., Energetic Low-Melting Salts of Simple Heterocycles, Propellants, Explos., Protech., 2003, 28, 174-180.
• [3] Wilkes J.S., Zaworotko M.J., Air and Water Stable 1-Ethyl-3-methylimidazolium Based Ionic Liquids, J. Chem. Soc. Chem. Commun., 1992, 965-967.
• [4] Shackelford S.A., Belletire J.L., Boatz J.A., Schneider S., Wheaton A.K., Wight B.A., Hudgens L.M., Ammon H.L., Strauss S.H., Pairing Heterocyclic Cations with closo-Icosahedral Borane and Carborane Anions. I. Benchtop Aqueous Synthesis of Binary Triazolium and Imidazolium Salts with Limited Water Solubility, Org. Lett., 2009, 11, 2623-2626.
• [5] Larsen A.S., Holbrey J.D., Tham F.S., Reed C.A., Designing Ionic Liquids: Imidazolium Melts with Inert Carborane Anions, J. Am. Chem. Soc., 2000, 122, 7264-7272.
• [6] Zhu Y., Ching C., Carpenter K., Xu R., Selvaratnam S., Hosmane N.S., Maguire J.A., Synthesis of the Novel Ionic Liquid [N-pentylpyridinium]+ [closo-CB11H12]–and Its Usage as a Reaction Medium in Catalytic Dehalogenation of Aromatic Halides, Appl. Organometal. Chem., 2003, 17, 346-350.
• [7] (a) Grimes R.N., Supercarboranes, Angew. Chem., Int. Ed., 2003, 42, 1198-1200; (b) Muetterties E.L., Knoth W.H., Polyhedral Boranes, M. Dekker, New York 1969.
• [8] The hot plate surface temperature could be as high as 281 °C. This was the temperature setting required by a computerized hot plate/stirrer to maintain the same oil bath at 165 ºC in the same fumehood location.
• [9] Shackelford S.A., Role of Thermochemical Decomposition in Energetic Material Initiation Sensitivity and Explosive Performance, Centr. Europ. J. Energ. Mater., 2008, 5, 75-101.