Highly Energetic Tetraazidoborate Anion and Boron Triazide Adducts

Abstract

The first crystal structures of the highly energetic tetraazidoborate anion and boron triazide adducts with quinoline and pyrazine as well as of tetramethylpiperidinium azide have been determined. Synthesis procedures and thorough characterization by spectroscopic methods of these hazardous materials are given. Quantum chemical calculations were carried out for B(N(3))(4)(-), B(N(3))(3), C(5)H(5)N.B(N(3))(3), (N(3))(3)B.NC(4)H(4)N.B(N(3))(3), and the hypothetical C(3)H(3)N(3).[B(N(3))(3)](3) at HF, MP2, and B3-LYP levels of theory. The structure of tetraazidoborate was optimized to S(4) symmetry and confirmed the results obtained from the X-ray diffraction analysis. The dissociation enthalpies for the pyridine (model for quinoline) as well as for the pyrazine adduct were calculated. For pyridine-boron triazide a value of 10.0 kcal mol(-1) (for pyrazine-bis(boron triazide) an average of 2.35 kcal mol(-1) per BN unit) was obtained.

Adducts of (C6F5)3B with Selected Nitrogen

“…The BϪN distance of 3 (1.644 (3) Å ) is longer than in 1 and 2, but still shorter than the very long BϪN distances of 4 (1.678 (3) Å /1.687(3) Å ), displaying clearly a stronger BϪN coordination in 3 compared to 4. A similar observation was also made for the 1:1 quinoline-boron triazide and the 1:2 pyrazine-bis(boron triazide) adduct, in which the latter BϪN distance is significantly longer (1.657(2) Å ) [16]. However, both distances are the longest observed (C 6 F 5 ) 3 BϪN distance reported up to now, but are shorter than the longest reported BϪN distance in B 2 Cl 4 ·2NMe 3 (1.756 Å ) [17].…”

N,N′-Diorganylsubstituted Hydrazinium Azides

“…Solutions of HN 3 in Ether were prepared from sodium azide and HBF 4´E t 2 O. [11] ± NMR: Jeol EX 400, 1 H (400.0 MHz), 13 …”

Stickstoffreiche energetische Salze und ionische Flüssigkeiten

“…[77] Bei der Umsetzung von 2,2,6,6-Tetramethylpiperidino-bordiazid mit HN 3 entstand 2,2,6,6-Tetramethylpiperidinium-tetraazidoborat (103). [78] Ebenfalls bekannt sind verschiedene Metallazide und binäre Salze von Azidokomplexen. [79] …”