4.4 Methods
117
4.4 Methods
Sample Preparation
NTO synthesis. 3-nitro-1,2,3-triazol-5-one (NTO) was prepared by nitration of TO
(prepared by Dr. S. Kennedy, School of Chemistry, University of Edinburgh),
according to Scheme 4.1 [30]. TO (ca. 5 g, 60 mmol) was dissolved in excess concentrated nitric acid (70%), and held at 55 °C for ca. 45 min. The nitration was quenched
in an ice bath, filtered and rinsed in ice water. Purity was verified by X-ray powder
diffraction.
Synthesis of FOX-7. Preparation of 1,1-diamino-2,2-dinitroethene (DADNE,
FOX-7) followed from Scheme 4.2 [30]. 2-methyl-4,6-pyrimidinedione (6.0 g,
0.05 mol) was dissolved in concentrated H 2 SO 4 (95%, 45 mL), at temperatures <
30 °C. Concentrated HNO 3 (99%, 20 mL) was subsequently added dropwise, maintaining temperatures < 20 °C, and the sample stirred for 3 h. The resulting material
was rinsed in concentrated H 2 SO 4 , added to deionized water (100 mL) and stirred
for 2 h. The resulting product was analysed by
1 H and
13 C NMR in DMSO, and
subsequently by X-ray powder diffraction.
TATB and β-HMX. Samples of these materials were taken from available stock. βHMX was provided by the Cavendish Laboratories, University of Cambridge. TATB
was synthesised by C. Henderson (School of Chemistry, University of Edinburgh).
Samples were used as provided, without further purification.
Condensed Matter Calculations
The PBE-D2 scheme has been previously demonstrated to work very well for molecular energetic materials [31–33]. It was therefore chosen as a starting point for the
calculations presented here. All input structures were taken from the Cambridge
HN
NH
N
NO 2
O
HN
NH
N
O
70% HNO 3
Scheme 4.1 Synthetic approach for the synthesis of NTO
Scheme 4.2 Synthetic approach for preparation of FOX-7
117
4.4 Methods
Sample Preparation
NTO synthesis. 3-nitro-1,2,3-triazol-5-one (NTO) was prepared by nitration of TO
(prepared by Dr. S. Kennedy, School of Chemistry, University of Edinburgh),
according to Scheme 4.1 [30]. TO (ca. 5 g, 60 mmol) was dissolved in excess concentrated nitric acid (70%), and held at 55 °C for ca. 45 min. The nitration was quenched
in an ice bath, filtered and rinsed in ice water. Purity was verified by X-ray powder
diffraction.
Synthesis of FOX-7. Preparation of 1,1-diamino-2,2-dinitroethene (DADNE,
FOX-7) followed from Scheme 4.2 [30]. 2-methyl-4,6-pyrimidinedione (6.0 g,
0.05 mol) was dissolved in concentrated H 2 SO 4 (95%, 45 mL), at temperatures <
30 °C. Concentrated HNO 3 (99%, 20 mL) was subsequently added dropwise, maintaining temperatures < 20 °C, and the sample stirred for 3 h. The resulting material
was rinsed in concentrated H 2 SO 4 , added to deionized water (100 mL) and stirred
for 2 h. The resulting product was analysed by
1 H and
13 C NMR in DMSO, and
subsequently by X-ray powder diffraction.
TATB and β-HMX. Samples of these materials were taken from available stock. βHMX was provided by the Cavendish Laboratories, University of Cambridge. TATB
was synthesised by C. Henderson (School of Chemistry, University of Edinburgh).
Samples were used as provided, without further purification.
Condensed Matter Calculations
The PBE-D2 scheme has been previously demonstrated to work very well for molecular energetic materials [31–33]. It was therefore chosen as a starting point for the
calculations presented here. All input structures were taken from the Cambridge
HN
NH
N
NO 2
O
HN
NH
N
O
70% HNO 3
Scheme 4.1 Synthetic approach for the synthesis of NTO
Scheme 4.2 Synthetic approach for preparation of FOX-7