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Wayne State University

Synthesis And Characterization Of Metal Complexes Containing Tetrazolate, Poly(tetrazolyl)borate, And Aryl Pentazole Ligands As High Energy Density Materials

Abstract

dc:description.abstract

<p>Heavier alkaline earth metal tetrazolates have been prepared as cryatals contain aqua ligands and as anhydrous powders, and were characterized by spectral and analytical methods. Potassium bis(tetrazolyl)borate complexes K(BH<sub>2</sub>(RCN<sub>4</sub>)<sub>2</sub>)(H<sub>2</sub>O)<sub>n</sub> (R = H, Me, NMe<sub>2</sub>, and NiPr<sub>2</sub>) and their 18-crown-6 adducts have been synthesized. In the solid state, complexes where R = H and Me have B-N bonds to the nitrogen atoms proximal to the carbon atom, whereas those with R = NMe<sub>2</sub> and NiPr<sub>2</sub> possess isomeric B-N bonds to the nitrogen atoms distal to the core carbon. With small R groups, the bis(tetrazolyl)borate ligands adopt bridging μ<sub>2</sub> coordination modes to the [18-crown-6]<sup>+</sup> fragments, while with larger R groups, they adopt chelating κ<sup>3</sup>-N,N',H coordination modes in the 18-crown-6 adducts. Bis(5-methyltetrazolyl)borate complexes of lithium and heavier alkaline earth metals have been prepared. The new group 2 metal complexes were structurally characterized. Crystals of sodium cyano(tetrazolyl)borate complexes with or without methanol ligands have been prepared. The methanol ligands are lost rapidly at 23 °C from crystals of Na(H<sub>2</sub>B(CN)(HCN<sub>4</sub>))(CH<sub>3</sub>OH) and Na(H<sub>2</sub>B(CN)(MeCN<sub>4</sub>))(CH<sub>3</sub>OH)·(CH<sub>3</sub>OH) once they are isolated from the solution.</p> <p>All of the new complexes mentioned above are air stable and thermally stable between 210 °C and 325 °C. They are insensitive toward impact, friction, and electrostatic discharge. The new complexes have potential use as propellants or secondary energetic materials; the barium tetrazolates may behave as primary energetic materials. The group 2 metal complexes are good candidates for colorants in pyrotechnic compositions. The potassium and sodium complexes can serve as starting materials to make other high nitrogen content bis(tetrazolyl)borate and cyano(tetrazolyl)borate complexes, respectively.</p> <p>A series of rhenium isocyanate complexes (ç<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)Re(CO)(NCO)(N<sub>2</sub>Ar) was obtained by treatment of the specific rhenium aryldiazenido complexes [(ç<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)Re(CO)<sub>2</sub>(N<sub>2</sub>Ar)][BF<sub>4</sub>] (ç<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)Re(CO)(NCO)(N<sub>2</sub>Ar) (Ar = 4-methoxyphenyl, 2,4-dimethoxyphenyl, 3,4,5-trimethoxyphenyl, 2-trifluoromethylphenyl, and phenyl) with sodium azide. Treatment of CpRe(CO)<sub>2</sub>(THF) with Et<sub>2</sub>NC<sub>6</sub>H<sub>5</sub>N<sub>5</sub> made in situ affords the isocyanate complex (ç<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)Re(CO)(NCO)(N<sub>2</sub>C<sub>6</sub>H<sub>5</sub>NEt<sub>2</sub>) and the methoxycarbonyl complex (ç<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)Re(CO)(COOCH<sub>3</sub>)(N<sub>2</sub>C<sub>6</sub>H<sub>5</sub>NEt<sub>2</sub>). The attempted preparation of rhenium aryl pentazole complexes did not proceed to form the desired products.</p>

Degree

thesis:*
Name thesis:degree_name
Ph.D.
Level thesis:degree_level
Open Access Dissertation
Discipline thesis:degree_discipline
Chemistry
Year dc:date.available
2010

Author and committee

dc:creator, dc:contributor.*
Author dc:creator
  • Lu, Dongmei
Contributors dc:contributor
  • Charles H. Winter

Subjects

dc:subject × 1

Identifiers

dc:identifier.*
OAI identifier oai:identifier
oai:digitalcommons.wayne.edu:oa_dissertations-1067

Chain of custody

source
Harvested from
Wayne State University
Base URL
digitalcommons.wayne.edu/do/oai/
Last updated
2026-07-24
Source record
OAI-PMH GetRecord
citation

Lu, Dongmei. Synthesis And Characterization Of Metal Complexes Containing Tetrazolate, Poly(tetrazolyl)borate, And Aryl Pentazole Ligands As High Energy Density Materials. Open Access Dissertation thesis, 2010. https://digitalcommons.wayne.edu/oa_dissertations/68