Synthesis and Structural Investigation of Brightly Colored Organoammonium Violurates

Abstract

Nine new organoammonium violurates [R 1 R 2 R 3 NH][C 4 H 2 N 3 O 4 ] [R 1 (4), R 3 = C 6 H 2 Me 2 -4,5-NH 2 -2 (5); R 1 = H, R 2 = R 3 = Et (6), iPr (7); R 1 = H, R 2 /R 3 = (-CH 2 -) 4 (8); R 1 = R 2 = R 3 = Et (9); R 1 = R 2 = Me, R 3 = (CH 2 ) 2 NMe 2 (10)] were prepared by treatment of violuric acid (1) with a variety of primary, secondary, and tertiary amines. With the exception of orange 5, all these violurate salts form bright blue or blue-purple crystalline solids. The acidic triethylammo-* Prof. Dr. F. T. Edelmann 36 nium violurate [NHEt 3 ]H[C 4 H 2 N 3 O 4 ] 2 ·H 2 O (9a) was isolated in the form of red-violet, plate-like crystals by the reaction of violuric acid hydrate with triethylamine in a molar ratio of 2:1 in ethanol. All compounds were fully characterized by their IR and NMR ( 1 H, 13 C) data as well as elemental analyses. X-ray crystal structures determinations of 2, 7, and 9a revealed supramolecular self-assembly through networks of N-H···N and N-H···O hydrogen bonds in the crystalline state.

Synthesis and Structural Investigation of a Complete Series of Brightly Colored Alkali Metal 1,3‐Dimethylviolurates

“…Figure 1 illustrates the characteristic solid‐state colors of all title compounds 3 – 7 . Similar to the previously reported organoammonium violurates [ 29 ] the bright colors of the crystals range from orange‐red to blue.…”

“…Figure 1 illustrates the characteristic solid-state colors of all title compounds 3-7. Similar to the previously reported organoammonium violurates [29] the bright colors of the crystals range from orange-red to blue. All new compounds were fully characterized through IR, 1 H NMR and 13 C NMR spectroscopy as well as elemental analyses.…”

Assembling Polyiodides and Iodobismuthates Using a Template Effect of a Cyclic Diammonium Cation and Formation of a Low-Gap Hybrid Iodobismuthate with High Thermal Stability

“…Each nitrogen atom of HpipeH 2 2+ has two hydrogen atoms and employs them to form hydrogen bonds with the anionic part. In the crystal structure of (HpipeH 2 ) 2 Bi 2 I 10 ·2H 2 O, one nitrogen atom is involved in two (N)H···I bonds with iodine atoms of two different Bi 2 I 10 4– anions, whereas another nitrogen atom forms one hydrogen bond of the same type and a (N)H···O hydrogen bond of 1.88 Å with solvent water, which is quite short compared to other organoammonium derivatives [ 40 ]. In this way, the HpipeH 2 2+ dication becomes surrounded by three Bi 2 I 10 4– anions and one water molecule.…”

“…The analysis of the crystal structures of hybrid iodobismuthates shows that features other than the dimensionality of the Bi/I substructure play an important role in controlling the band gap width. Namely, they are multifold weak interactions that include hydrogen bonds (mainly (N)H•••I) as well as interanionic I•••I interactions [36][37][38][39][40][41][42]. DFT calculations reveal that weak non-covalent bonds are capable of promoting charge mobility along the direction of spreading such bonds in the crystal structure [34][35][36][37][38][39].…”

Preparation of Al/Ni Reactive Multilayer Foils and its Application in Thermal Battery

“…The traditional heating materials used in the thermal battery Li/Li x system are mainly Zr/BaCrO 4 as ignition paper and Fe/KClO 4 as heating sheets, which have the characteristics of high gas production and low heat release. These defects during the discharge limit the shortening the activation time, which is difficult to meet the needs of the current weapon equipment , . Reactive Multilayer Foils (RMFs) is a kind of new energy material with high heat release and fast burning rate.…”