Girish M. Gore

Synthesis and characterization of 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine (BTATz): Novel high-nitrogen content insensitive high energy material

This paper reports the synthesis, characterization and thermolysis studies of 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine (BTATz) and 3-(1H-1,2,3,4-tetrazol-5-ylamino)-6-(3,5-dimethyl-pyrazol-1-yl)-s-tetrazine monohydrate (TADPTz). The synthesized BTATz and TADPTz have been characterized by spectroscopic techniques and the data obtained confirm their structure. TGA and DSC results suggested that BTATz decomposes in the range 265-350 degrees C and TADPTz in the range 245-275 degrees C respectively. The calculated energy of activation of BTATz and TADPTz is 212.69 and 257.29kJ/mol respectively. The experimentally determined DeltaH(f) value matches with theoretically computed heat of explosion. The computed volume of gases indicates that they can find application in gas generating compositions.

Studies on thermal decomposition mechanism of CL-20 by pyrolysis gas chromatography–mass spectrometry (Py-GC/MS)

The thermal decomposition study of CL-20 (hexanitrohexaazaisowurtzitane) using pyrolysis GC/MS was carried out mainly by electron impact (EI) mode. Chemical ionization (CI) mode was used for further confirmation of identified species. Mass spectrum of CL-20 decomposition products predominantly revealed fragments with m/z 81 and 96 corresponding to C(4)H(5)N(2)(+) and C(4)H(4)N(2)O(+) ions, respectively. The total ion chromatogram (TIC) of CL-20 pyrolysis shows peak within first 2 min due to the presence of low molecular weight gases. Peaks corresponding to several other products were also observed including the atmospheric gases. Cyanogen formation (C(2)N(2), m/z 52) observed to be enriched at the scan number 300-500. The low molecular mass range decomposition products formed by cleavage of C-N ring structure were found in majority. Additional structural information was sought by employing chemical ionization mode. The data generated during this study was instrumented in determining decomposition pathways of CL-20.

A DFT study of aminonitroimidazoles

Density functional theory (DFT) calculations at the B3LYP/aug-cc-pVDZ level were performed to explore the geometric and electronic structures, band gaps, thermodynamic properties, densities and performances of aminonitroimidazoles. The calculated performance properties, stabilities and sensitivities of the model compounds appear to be promising compared with those of the known explosives 2,4-dinitro-1H-imidazole (2,4-DNI), 1-methyl-2,4,5-trinitroimidazole (MTNI), hexahydro-1,3,5-trinitro-1,3,5-triazinane (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetraazocane (HMX). The position of the NH2 or the number of NO2 groups on the diazole presumably determines the structure, heat of formation, stability, sensitivity, density and performance of the compound.

DFT study on the structure and explosive properties of nitropyrazoles

Ab initio molecular orbital calculations at the B3LYP/aug-cc-pVDZ level have been carried out to explore the structure, stability, sensitivity and band gap of nitropyrazoles. Kamlet and Jacob equations were used to calculate the detonation velocity and detonation pressure of designed compounds. The explosive properties of polynitropyrazole-N-oxides appear to be higher compared with those of octanitrocubane and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexa azaisowurtzitane. The sensitivity, heat of explosion, density, detonation velocity and detonation pressure are presumably related to the number and the relative positions of NO2 groups on the pyrazole ring.

Silica–Sulfuric Acid Catalyzed Nitrodeiodination of Iodopyrazoles

Abstract We report here the synthesis of nitropyrazoles in good to excellent yields from iodopyrazoles over silica–sulfuric acid catalyst for the first time. The present procedure require less acid, offers a simplified workup procedure, and may be applied for the nitration of a wide variety of iodoazoles in drug and pharmaceutical industries. GRAPHICAL ABSTRACT

Microwave mediated fast synthesis of diaminoglyoxime and 3,4-diaminofurazan: key synthons for the synthesis of high energy density materials

This paper reports the first microwave-assisted synthesis of diaminoglyoxime (DAG) and diaminofurazan (DAF). The synthesis involved the vicarious nucleophilic substitution of H of glyoxime using hydroxylamine hydrochloride under microwave irradiation for 2 to 3 min to obtain DAG, which on further irradiation in alkali solution for 20 min yielded DAF. Conversion of glyoxime into DAF was also achieved in a one pot sequence in good overall yield using microwave irradiation.