Nitrolysis of dibenzylhexaazatetracyclic compounds Russ.Chem.Bull., Int.Ed., Vol. 66, No. 3, March, 2017
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M.p. 262—272 °C (from acetonitrile). Found (%): C, 55.45;
H, 5.16; N, 18.39. C28H30N8O8. Calculated (%): C, 55.44;
H, 4.98; N, 18.47. IR, ν/cm–1: 3077, 3044, 3017, 2917, 2863,
1661, 1605, 1517, 1395, 1347, 1290, 1259, 1131, 1038, 995, 853,
813, 773, 699, 629, 547. 1H NMR, δ: 1.91—2.11 (m, 12 H,
CH3CO); 4.08—4.25 (m, 4 H, CH2); 5.33—5.56 (m, 4 H, CH);
6.25—6.68 (m, 2 H, CH); 7.79 (br.s, 4 H, Ar); 8.27 (d, 4 H, Ar,
J = 10.4 Hz). 13C NMR, δ: 20.70, 21.98 (CH3CO); 54.14, 54.75
(CH2); 68.14, 68.62, 69.76, 70.72, 71.49, 72.67 (CH); 123.38,
129.36, 129.89 (CH, Ar); 146.76, 146.92 (C, Ar); 167.04, 167.99,
168.08 (CH3CO).
B. Glacial AcOH (14 mL) and Ac2O (8 mL) were placed
into a threeꢀneck flask equipped with a stirrer and a thermoꢀ
meter, followed by the addition of 99% HNO3 (4 mL) with coolꢀ
ing in an iceꢀwater bath. Compound 2 (4.6 g) was added to the
prepared nitration mixture cooled to 0 °C and this was allowed to
stand for 3 h at 0 °C. Then, the reaction mixture was poured into
a mixture of ice with water (300 g). A precipitate was filtered off,
washed with water, and dried in air. The product was treated
with Me2CO (35 mL), after 2 h filtered off, washed with Me2CO,
and dried in air to obtain a precipitate (1.5 g). An additional
amount of the precipitate (0.7 g) was isolated by the concentraꢀ
tion of Me2CO. The TLC data showed that the combined preꢀ
cipitate contained two main products; 0.7 g of the precipitate
was dissolved in MeCN and separated by preparative chromꢀ
atography, eluent MeCN : MeOH (10 : 1, v/v). Two main prodꢀ
ucts were isolated: the sample (0.28 g, 16.0%) with Rf = 0.33
(TLC), the IR and NMR spectra and the results of elemental
analysis of which were similar to those for compound 3 obtained
earlier; the sample (0.15 g, 10.0%) with Rf = 0.56 (TLC) correꢀ
sponding to compound 4.
2,6,8,12ꢀTetraacetylꢀ4ꢀnitroꢀ10(pꢀnitrobenzyl)ꢀ2,4,6,8,10,12ꢀ
hexaazatetracyclo[5.5.0.03,11.05,9]dodecane (4). M.p. 260—265 °C.
Found (%): C, 49.03; H, 4.51; N, 21.62. C21H24N8O8. Calculatꢀ
ed (%): C, 48.84; H, 4.68; N, 21.70. IR, ν/cm–1: 3020, 2920,
2845, 1665, 1600, 1550, 1520, 1395, 1345, 1290, 1255, 1160,
1125, 1038, 945, 887, 855, 773, 725, 629, 547. 1H NMR,
δ: 2.07—2.14 (m, 12 H, CH3CO); 4.08—4.28 (m, 2 H, CH2);
5.57—5.90 (m, 2 H, CH); 6.47—7.75 (m, 4 H, CH); 7.49 (d, 2 H,
Ar, J = 10.8 Hz); 8.20 (d, 2 H, Ar, J = 11.4 Hz). 13C NMR, δ:
20.56, 50.70, 21.72 (CH3CO); 54.91 (CH2); 67.15, 68.86, 69.71,
70.41, 71.6, 73.4 (CH); 123.30, 129.62 (CH, Ar); 145.78, 146.99
(C, Ar); 166.80, 168.20 (CH3CO).
2,6,8,12ꢀTetraacetylꢀ4,10ꢀdi(pꢀnitrobenzoyl)ꢀ2,4,6,8,10,12ꢀ
hexaazatetracyclo[5.5.0.03,11.05,9]dodecane (6). 2,6,8,12ꢀTetraꢀ
acetylꢀ2,4,6,8,10,12ꢀhexaazatetracyclo[5.5.0.03,11.05,9]dodecane
(6.0 g, 0.017 mol), anhydrous MeCN (70 mL), and pꢀnitroꢀ
benzoyl chloride (26 g, 0.14 mol) were placed into a flatꢀbottom
flask. The flask was placed on a magnetic stirrer and refluxed
with a refluxed condenser for 7 h. The resulting solution was
concentrated on a rotary evaporator. The residue was treated
with EtOH (150 mL). The product was filtered off, washed with
EtOH (2×30 mL), and dried in air. Compound 6 (7.0 g, 0.012 mol,
66.7%) was obtained after crystallization from a mixture of
EtOH—MeCN (280 mL, 7 : 3, v/v). M.p. 268—272 °C (from
a mixture of EtOH—MeCN). Found (%): C, 52.3; H, 4.18;
N, 17.53. C28H26N8O10. Calculated (%): C, 53.00; H, 4.13;
N, 17.66. IR, ν/cm–1: 3109, 3043, 2917, 2863, 1678, 1603, 1525,
1402, 1355, 1305, 1142, 1053, 860, 767, 721, 706, 622, 515.
1H NMR, δ: 2.02 (s, 6 H, CH3CO); 2.14 (s, 6 H, CH3CO);
6.21—7.05 (m, 6 H, CH); 7.85 (d, 4 H, Ar, J = 10.8 Hz); 8.38
(d, 4 H, Ar, J = 11.4 Hz). 13C NMR, δ: 20.85, 21.91 (CH3CO);
63.55, 68.65, 71.60 (CH); 123.72, 129.33 (CH, Ar); 139.19,
148.75 (C, Ar); 167.65, 167.89 (CH3CO); 169.44 (CO).
Synthesis of compounds 7 and 8. A 99% HNO3 (21 mL) and
NH4NO3 (10.5 g) were placed into a threeꢀneck flask equipped
with a stirrer, a thermometer, and a reflux condenser. Then,
product 6 (6.1 g) was added to the obtained solution. The reacꢀ
tion mixture was allowed to stand for 8 h at 100—110 °C, cooled,
and poured into a mixture of ice with water. A precipitate was
filtered off, washed with water (6×10 mL), and dried in air to
obtain a mixture of products (5.8 g). According to the HPLC
data, the mixture contained 2% of compound 1, 25% of comꢀ
pound 8, and 70% of compound 3. After crystallization from
MeCN, a mixture of compounds 8 and 7 (4.4 g) was obtained.
For analytical purposes, 0.7 g of the mixture was separated by
preparative column chromatography. Eluent oꢀxylene : Me2CO =
= 7 : 1 (v/v). Two products were isolated: the sample (0.45 g)
with Rf = 0.64 (TLC) corresponding to compound 7 and the
sample (0.18 g) with Rf = 0.4 (TLC) corresponding to compound 8.
4,10ꢀDi(pꢀnitrobenzoyl)ꢀ2,6,8,12ꢀtetranitroꢀ2,4,6,8,10,12ꢀ
hexaazatetracyclo[5.5.0.03,11.05,9]dodecane (7). M.p. 242—244 °C
(decomp.). Found (%): C, 37.8; H, 2.09; N, 26.15. C20H14N12O14.
Calculated (%): C, 37.16; H, 2.18; N, 26.00. IR, ν/cm–1: 3112,
3026, 2923, 2858, 1690, 1619, 1601, 1567, 1526, 1402, 1352,
1
1310, 1264, 1182, 953, 863, 756, 699, 656, 571. H NMR, δ:
6.75—7.90 (m, 6 H, CH); 7.93 (d, 4 H, Ar, J = 8 Hz); 8.46 (d, 4 H,
Ar, J = 8 Hz). 13C NMR, δ: 73.46 (CH); 124.00 (CH, Ar);
130.03 (CH, Ar); 137.61, 149.29 (C, Ar); 168.88 (C, CO).
2ꢀAcetylꢀ4,10ꢀdi(pꢀnitrobenzoyl)ꢀ6,8,12ꢀtrinitroꢀ2,4,6,8,10,12ꢀ
hexaazatetracyclo[5.5.0.03,11.05,9]dodecane (8). M.p. 226—228 °C.
Found (%): C, 40.98; H, 2.49; N, 24.0. C22H17N11O13. Calculatꢀ
ed (%): C, 41.07; H, 2.66; N, 23.95. IR, ν/cm–1: 3111, 3034, 2921,
2852, 1691, 1603, 1556, 1527, 1398, 1353, 1311, 1266, 1175, 1105,
953, 863, 758, 701, 662, 571. 1H NMR, δ: 2.16 (s, 3 H, CH3CO);
6.45—7.72 (m, 6 H, CH); 7.89 (d, 4 H, Ar, J = 8 Hz); 8.45 (d, 4 H,
Ar, J = 8 Hz). 13C NMR, δ: 20.05 (CH3CO); 69.44 (CH); 124.06,
129.90 (CH, Ar); 137.89, 149.24 (C, Ar); 161.02, 168.2 (C, CO).
2,6,8,12ꢀTetraacetylꢀ4ꢀnitroꢀ10(pꢀnitrobenzyl)ꢀ2,4,6,8,10,12ꢀ
hexaazatetracyclo[5.5.0.03,11.05,9]dodecane (4). A 99% HNO3
(53 mL) and NH4NO3 (20.0 g) were placed into a threeꢀneck
flask equipped with a stirrer and a thermometer. Product 2 (10.0 g)
was added to the obtained solution at a temperature ≤10 °C. The
reaction mixture was allowed to stand for 6 h at 20—25 °C and
poured into a cooled 25% aqueous (NH4)2SO4 (280 g) with stirꢀ
ring on a magnetic stirrer. The resulting suspension was neutralꢀ
ized to рH = 3—5 with a 25% aqueous ammonia (75 mL). Durꢀ
ing these manipulations, ice was added to the mixture in order to
maintain the temperature below 10 °C. The suspension was alꢀ
lowed to stand for 16 h, a precipitate was filtered off, washed
with water (6×20 mL), and dried in air. The filtrate was extractꢀ
ed with AcOEt (3×75 mL) and after standing for a while filtered
off through a paper filter. The obtained product and the extract
were placed in a flask and stirred with a slight reflux 2 h. Then,
the suspension was cooled to room temperature and after 2 h
filtered off. A precipitate was washed with AcOEt (2×10 mL)
and dried in air to obtain a mixture of three isomers of comꢀ
pound 4 (9.3 g, 93.5%). According to the HPLC data, the conꢀ
tent of the main product was 68.4%. The crystallization from
nitromethane allowed us to increase the melting point form
270 °C (decomp.) to 303—304 °C (decomp.), as well as to inꢀ
crease the content of the paraꢀisomer of compound 4 to 89.0%.
The IR and NMR spectra and the results of elemental analysis
correspond to those obtained earlier.