Syntheses and Thermal Behaviors of Rb(FOX-7)·H₂O and Cs(FOX-7)·H₂O

Abstract

Two new energetic organic alkali metal salts, 1,1-diamino-2,2-dinitroethylene rubidium salt [Rb(FOX-7)·H2O] and 1,1-diamino-2,2-dinitroethylene cesium salt [Cs(FOX-7)·H2O], were synthesized by reacting of 1,1-diamino-2,2-dinitroethylene (FOX-7) and rubidium chloride or cesium chloride in alkali methanol aqueous solution, respectively. The thermal behaviors of Rb(FOX-7)·H2O and Cs(FOX-7)·H2O were studied with DSC and TG methods. The critical temperatures of thermal explosion of the two compounds are 216.22 and 223.73 o C, respectively. Specific heat capacities of the two compounds were determined with a micro-DSC method, and the molar heat capacities are 217.46 and 199.47 J mol -1 K -1 at 298.15 K, respectively. The adiabatic times-to-explosion were also calculated to be a certain value of 5.81 -6.36 s for Rb(FOX-7)·H2O, and 9.92 -10.54 s for Cs(FOX-7)·H2O. After FOX-7 becoming alkali metal salts, thermal decomposition temperatures of the compounds heighten with the rise of element period, but thermal decomposition processes become intense.

Theoretical insights into the synthesis mechanism of two amino-substituted derivatives of FOX-7

“…In addition, due to the existence of lone pair electrons on both amino groups of FOX-7, such a structure itself can also react as a nucleophile, and the cyclic compound 4,5-dihydroxy-2-(dinitromethylene)-imidazolidine (DDNI) [13] can be generated from the reaction of FOX-7 with glyoxal based on this. In addition, other types of reactions can occur with FOX-7 [14][15][16][17].…”

Thermolysis, Nonisothermal Decomposition Kinetics, Specific Heat Capacity and Adiabatic Time-to-Explosion of [Cu(NH3)4](DNANT)2 (DNANT= Dinitroacetonitrile)

“…So much attention is focused on designing new energetic molecules. 1,1-Diamino-2,2-dinitroethylene (FOX-7) is a novel high-energy material with high thermal stability and low sensitivity to impact and friction. − FOX-7 is a representative “push-pull” nitro-enamine and presents certain acidic properties. ,− FOX-7 can react with some nucleophiles to synthesize many new energetic derivatives. − Some energetic salts and metal complexes of FOX-7 also were reported recently. ,− …”

Theoretical insights into the synthesis mechanism of two amino‐substituted derivatives of FOX‐7

“…In addition, due to the existence of lone pair electrons on both amino groups of FOX-7, such a structure itself can also react as a nucleophile, and the cyclic compound 4,5-dihydroxy-2-(dinitromethylene)imidazolidine (DDNI) [16] can be generated from the reaction of FOX-7 with glyoxal based on this. In addition, other types of reactions can occur with FOX-7 [17][18][19][20].…”