Screening for energetic compounds based on 1,3-dinitrohexahydropyrimidine skeleton and 5-various explosopheres: molecular design and computational study

Abstract

In this paper, twelve 1,3-dinitrohexahydropyrimidine-based energetic compounds were designed by introducing various explosopheres into hexahydropyrimidine skeleton. Their geometric and electronic structures, heats of formation (HOFs), energetic performance, thermal stability and impact sensitivity were discussed. It is found that the incorporation of electron-withdrawing groups (–NO2, –NHNO2, –N3, –CH(NO2)2, –CF(NO2)2, –C(NO2)3) improves HOFs of the derivatives and all the substituents contribute to enhancing the densities and detonation properties (D, P) of the title compounds. Therein, the substitution of –C(NO2)3 features the best energetic performance with detonation velocity of 9.40 km s−1 and detonation pressure of 40.20 GPa. An analysis of the bond dissociation energies suggests that N–NO2 bond may be the initial site in the thermal decompositions for most of the derivatives. Besides, –ONO2 and –NF2 derivatives stand out with lower impact sensitivity. Characters with striking detonation properties (D = 8.62 km s−1, P = 35.08 GPa; D = 8.81 km s−1, P = 34.88 GPa), good thermal stability, and acceptable impact sensitivity (characteristic height H50 over 34 cm) lead novel compounds 5,5-difluoramine-1,3-dinitrohexahydropyrimidine (K) and 5-fluoro-1,3,5-trinitrohexahydropyrimidine (L) to be very promising energetic materials. This work provides the theoretical molecular design and a reasonable synthetic route of L for further experimental synthesis and testing.

Exploring Organic Cathode Materials for Lithium-Ion Batteries through Fragment Bonding and Discharge Simulation

“…The numbers along the left and top axes are the fragment indices. White blocks indicate calculation errors and the synthetic accessibility score greater than 4.5 …”

Facile fabrication of functionalized pyrimidine derivatives: constructing a new family of high performance and less sensitive energetic compounds

“…In principle, the energetic materials with BDE > 80 kJ mol −1 meet the stability requirements of energetic materials. 39 It can be estimated that all the compounds are stable and that the aromatic backbone and electron-donating –NH 2 and –NHNH 2 groups help in achieving the stability. The energy gap (Δ E LUMO–HOMO ) between the highest occupied molecular orbitals (HOMOs) and the lowest unoccupied molecular orbitals is also essential for evaluating the chemical stability of molecules with similar skeletons.…”

“…To evaluate the potential of the compounds as a possible future component of solid rocket propellants, we calculated the performances of reported compounds using the recently described Klapötke and Suceska method 39 of specific impulse with various composite mixtures containing 10% glycidyl azide polymer (GAP), 15% nitroglycerin (NG), 18% aluminum, a variable percentage (57%) of the oxidizer ammonium perchlorate (AP) and an energetic filler to attain the oxygen balance −33% with respect to CO 2 , which corresponds to modern propellant formulation (70% AP, 16% Al, 12% HTPB and 2% epoxy) with practical applications. Using this method, the calculated specific impulses (with the EXPLO-5 (v 6.02.02) software) of compounds 2 , 3 , 4 , 9 , and 10 are 268.3, 271.7, 270.3, 268, and 272 s, respectively (detailed calculation (ESI, Table S10†), which offers better impulse values than a modern propellant formulation (70% AP, 16% Al, 12% HTPB and 2% epoxy) with a calculated specific impulse of 264 s. 40…”

Modeling Photolytic Decomposition of Energetically Functionalized Dodecanes

“…For all of the functionalized dodecane QY results, the most probable decomposition pathway is the cleavage of the trigger linkage, or the weakest bond in an explosive molecule that is often thought to be responsible for explosive decomposition in the commonly used drop-weight impact test. − As a reminder, QY results between 4 and 8 eV are not comparable, but the results within each energy regime are. For materials containing azides, the trigger linkage is considered to be N–N 2 . , For the nitro class explosives, the trigger linkage is thought to be the X–NO 2 bond where X = N, C, or O.…”