New Insights into the Stability of Anhydrous 2H-Imidazolium Fluoride and its High Dissolution Capability toward a Strongly Hydrogen-Bonded Compound

Abstract

Fluorides have been widely applied in pharmaceutical, medicinal, and materials science as well as in fine chemical manufacturing. The performance of fluorides, however, can be markedly affected by the water content. One previous study et al. Phys. Chem. Chem. Phys. 2008, 10, 5050) suggested that anhydrous 1,3-dimethylimidazolium fluoride ([DMIm]F) was unstable since the fluoride undergoes a self-decomposition reaction. Herein we first show quantum-chemical calculation evidence that although gas-phase [DMIm]F is unstable, the bulk phase of anhydrous [DMIm]F is quite stable. We then demonstrate the successful synthesis of the anhydrous [DMIm]F compound via the reaction between 1,3-dimethylimidazolium iodide and silver fluoride. Importantly, we find that anhydrous [DMIm]F possesses a high dissolution capability toward 1,3,5-triamino-2,4,6trinitrobenzene (TATB), although it is known that TATB is hardly dissolved in many common organic solvents. Our Born− Oppenheimer molecular dynamics (BOMD) simulations further show that the high dissolving ability of anhydrous [DMIm]F toward TATB can be attributed to the chemical reaction between the F − anion and the TATB molecules, which disrupts the strong hydrogen-bonding interaction among the TATB molecules. Alternatively, water molecules in hydrous [DMIm]F tend to form a hydration layer around the F − anion, thereby preventing F − from reacting with the TATB molecule. This result explains why TATB is barely dissolved in hydrous [DMIm]F.

Full-nitro-nitroamino cooperative action: Climbing the energy peak of benzenes with enhanced chemical stability

“…This is mainly because the extremely strong intramolecular hydrogen bonds ( Fig. 3, A and E ) passivate the amino groups of TATB, resulting in low reactivities ( 31 , 32 ). This may also explain why TATB has not been successfully nitrated to date since it was first prepared in 1888 ( 33 ).…”

Anhydrous N,N-Dimethyl-N,N-Dineopentylammonium Fluoride Electrolyte for Fluoride Ion Batteries

“…Tetraalkylammonium fluorides, including Np 1 F and Np 2 F, are typically prepared by first reacting a tetraalkylammonium iodide starting material with silver oxide to give the tetraalkylammonium hydroxide intermediates, followed by neutralization with aqueous hydrofluoric acid. ,, Ammonium fluorides are extremely hygroscopic, however, so obtaining anhydrous products under this reaction scheme is difficult. ,− To remove the residual water content, a harsh drying processlong periods under high vacuum at high temperature combined with azeotropic distillationis required. ,,− The use of strongly corrosive reagents such as hydrofluoric acid also poses inherent safety risks, particularly if the process is to be carried out at an industrial scale. − Therefore, milder and safer synthetic methods are highly desirable.…”

Metal–Organic Framework-Derived Fe-Doped CoF2/NF Composite as Bifunctional Electrocatalyst for Oxygen Evolution and Hydrazine Oxidation

“…Among them, transition-metal fluorides are rarely wielded in the field of water splitting. The ionic bond formed between metal and fluorine is easily dissociated during the reaction process because fluorine has the largest electronegative characteristic among nonmetallic elements, which is conducive to the progress of water splitting. − At the same time, the coexistence of metal–oxygen and metal–fluorine bonds promotes surface reconstruction and enhances the conductivity of the catalysts. More importantly, hydrogen fluoride gas can etch the surface of materials, thereby increasing the number of active sites.…”