Alkylation of 5-(3,3-R,R′-2-oxido-1-triazeneoxymethyl)tetrazoles

Article abstract of DOI:10.1007/s11172-020-3014-1

Alkylation of 5-(3,3-R,R′-2-oxido-1-triazeneoxymethyl)tetrazole salts with iodomethane, dimethyl sulfate, chloroacetonitrile, and 1-chloromethoxy-3,3-dimethyl-1-triazene 2-oxide affords two isomers at positions 1 and 2 of the tetrazole ring as the major p

Full text of DOI:10.1007/s11172-020-3014-1

Russian Chemical Bulletin, International Edition, Vol. 69, No. 11, pp. 2153—2158, November, 2020
2153
Alkylation of 5-(3,3-R,R´-2-oxido-1-triazeneoxymethyl)tetrazoles
G. A. Smirnov and P. B. Gordeev
N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences,
47 Leninsky prosp., 119991 Moscow, Russian Federation.
E-mail: smir@ioc.ac.ru
Alkylation of 5-(3,3-R,R´-2-oxido-1-triazeneoxymethyl)tetrazole salts with iodomethane,
dimethyl sulfate, chloroacetonitrile, and 1-chloromethoxy-3,3-dimethyl-1-triazene 2-oxide
affords two isomers at positions 1 and 2 of the tetrazole ring as the major products. Tetrazoles
containing oxymethyltriazene oxide groups at positions 5 and 1 (or 5 and 2) were synthesized
for the first time.
Key words: tetrazoles, 1-oxy-1-triazene oxides, isomers, iodomethane, chloroacetonitrile,
dimethyl sulfate, 1-chloromethoxy-3,3-dimethyl-1-triazene 2-oxide, alkylation.
In the past five decades, research on developing new
energetic compounds as potential powerful explosives and
efficient components of rocket propellants and powerful
gunpowder has focused mainly on organic C-nitro com-
pounds, C-(polynitro) compounds, N-nitroamines, and
organic nitrates. The potential of these types of organic
compounds has been employed to a great extent, but is far
from being exhausted. Hence, the search for new energetic
compounds in other classes of organic and inorganic
compounds holds promise. It would also be of interest to
design new energetic materials by the synthesis of novel
compounds with previously unknown combinations of
available explosophoric groups.
In this respect, a relatively new class of organic com-
pounds, 1-oxy-1-triazene 2-oxides, has attracted atten-
tion. These compounds, which were first described in
the 1980s, are considered as promising nitric oxide
(NO) donors in living organisms and were extensively
studied in the past decades in attempting to design new
drugs based on these compounds for the treatment of
cardiovascular, kidney, and lung diseases, cancer, and
diabetes.1—5
Besides, due to a relatively high enthalpy of formation
of the triazene oxide moiety and the presence of reactive
oxygen, 1-oxy-1-triazene 2-oxide derivatives can be con-
sidered as energetic compounds, which may be of interest
as components of energetic composites. By performing
research along this line, we developed methods for the
synthesis of 1-oxy-1-triazene 2-oxide derivatives contain-
ing nitrate6—8 or azide9 groups, which may be considered
as potential energy-rich compounds. In the previous
study,10 we elaborated a method for the synthesis of the
previously unknown group of energy-rich compounds,
oxytriazene oxide derivatives of tetrazoles. Here, we in-
vestigated the reaction of tetrazole salts 1—4 with alkyl-
ating agents, such as iodomethane, dimethyl sulfate,
chloroacetonitrile, and 1-chloromethoxy-3,3-dimethyl-
1-triazene 2-oxide11 (Scheme 1).
The reactions were performed mainly in acetonitrile.
In order to investigate the effect of the solvent on the
Scheme 1
X = I, MeSO4
Compound
R
R´ Cat+
Compound
3
4a
4b
R + R´
(CH2)4
O(CH2CH2)2
O(CH2CH2)2
Cat+
K+
Compound
5a, 9a
6a, 10a
R
R´
Me Me
Et Et
Compound
7a, 11a
8a, 12a
R + R´
(CH2)4
O(CH2CH2)2
1a
1b
2
Me Me K+
Me Me Ag+
Et
K+
Et
K+
Et3NH+
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2153—2158, November, 2020.
1066-5285/20/6911-2153 © 2020 Springer Science+Business Media LLC

Smirnov and Gordeev
Me2NN2O2CH2Cl
2154
Russ. Chem. Bull., Int. Ed., Vol. 69, No. 11, November, 2020
Table 1. Yields (Y) and ratios of isomeric alkylation products of tetrazoles 1—4
Tetrazole
Cation
Isomer of
tetrazole
Alkylating agent
MeI
Me2SO4
Product Y (%)
ClCH2CN
Product Y (%)
Product Y (%)
Product
Y (%)
1a
1b
2
K+
K+
Ag+
Ag+
K+
K+
K+
K+
K+
1,5
2,5
1,5
2,5
1,5
2,5
1,5
2,5
1,5
5а
9a
5а
9a
6а
10а
7а
11а
8а
Traces
31
5а
9а
Traces
37
5b
9b
16
15
—
5c
9c
32
31
—
35
—
—
—
—
18
—
—
—
—
—
—
15
6а
7.5
6b
17
34
45
20
23
6c
19
19
22
22
25
26
10а
7а
11а
8а
40
10b
7b
11b
8b
10c
7c
11c
8c
3
50
Traces
42
34
4a
31
24
(31)*
35
12a
K+
2,5
32
12а
12b
34
12c
19
(24)*
—
—
4b
Et3NH+
Et3NH+
1,5
2,5
8а
12а
36
36
—
—
8b
12b
24
28
8c
12c
22
19
* The reaction was performed in DMSO.
course of the reaction, we used DMSO in several experi-
ments. Potassium, silver, and triethylammonium salts of
these tetrazoles were subjected to alkylation. Tetrazole
anions are known to be ambidentate.12 Generally, the
alkylation of tetrazole salts affords a mixture of alkylation
products at the N(1) and N(2) atoms of the tetrazole ring.
The reactions under consideration also usually produced
two isomers. Depending on the nature of tetrazole and the
alkylating agent, the total yield varied from 30 to 80%.
Meanwhile, some reactions gave N(2) isomers as the
major products, while N(1) isomers were detected in trace
amounts. The results of the investigation are summarized
in Table 1.
In the general case, the methylation of potassium salts
1a, 2, 3, and 4a produces isomers at the N(2) atom in high
yield. The exception is the alkylation of potassium salt 3
with iodomethane. In this case, the yield of N(1) isomer
7a is almost 1.5 times higher than the yield of N(2) isomer
11a. The methylation of silver salt 1b with iodomethane,
as opposed to the potassium salt, was found to give N(1)
isomer 5a. The yield of this compound was twice as high
as the yield of N(2) isomer 9a. Besides, the methylation
of salts 1a and 4a with iodomethane afforded 1-methyl-
1H-tetrazole 13 (see Ref. 13) in ca. 7% yield. Presumably,
the formation of this product is attributed to low stability
of compounds 5a and 8a under the reaction conditions.
The reaction of potassium salts 1a—4a with chloro-
acetonitrile furnishes both isomers 5b—8b and 9b—12b in
a total yield of 31—65% (Scheme 2).
The methylation of potassium salt 1a with iodometh-
ane affords compound 9a as the major product. The
methylation with dimethyl sulfate also gives isomer 9a
in a significantly higher yield compared to isomer 5a
(see Table 1).
The isomer ratio strongly depends on the nature of the
starting salt. Thus, in the case of 1a, the total yield of
Scheme 2
Compound
1a
2
R
R´
Me Me
Et Et
Cat+
K+
Compound
3
4a
4b
R + R´
(CH2)4
O(CH2CH2)2
O(CH2CH2)2
Cat+
K+
Compound
5b, 9b
6b, 10b
R
R´
Me Me
Et Et
Compound
7b, 11b
8b, 12b
R + R´
(CH2)4
O(CH2CH2)2
K+
K+
Et3NH+

5-(2-Oxido-1-triazeneoxymethyl)tetrazoles
Russ. Chem. Bull., Int. Ed., Vol. 69, No. 11, November, 2020
2155
Scheme 3
Compound
1a
2
R
Me
Et
R´
Me
Et
Cat+
K+
Compound
3
4a
4b
R + R´
(CH2)4
O(CH2CH2)2
O(CH2CH2)2
Cat+
K+
Compound
5c, 9c
6c, 10c
R
R´
Me Me
Et Et
Compound
7c, 11c
8c, 12c
R + R´
(CH2)4
K+
K+
O(CH2CH2)2
Et3NH+
the N(1) atom.14—16 Tetrazoles containing oxymethyl-
triazene oxide groups at positions 5 and 1 (or 5 and 2)
were synthesized for the first time. Most of these com-
pounds are low-melting crystalline solids, which are stored
without decomposition under ambient conditions. These
compounds are of interest as potential energetic com-
pounds and as possible NO donors in living organisms.
isomers was 31%, and the isomer ratio 5b : 9b was 1 : 1.
In the reaction of salt 2, the total yield of isomer increased
to 51%, with the isomer ratio 6b : 10b being 1 : 2. For 4a,
the yield of the alkylated products was 57%, and the isomer
ratio 8b : 12b was 1 : 1.48. The treatment of 3a with chloro-
acetonitrile resulted in the highest total yield (65%), but
the isomer ratio was unexpectedly reverse (7b : 11b was
2.25 : 1).
The reaction of salts 1a—4a with 1-chloromethoxy-
3,3-dimethyl-1-triazene 2-oxide (Scheme 3) occurred
most unequivocally. The total yields of isomers 5c—8c
and 9c—12c were 38—63%. Only in the reaction of 4a,
isomer 8c prevailed over 12c (1 : 1.38); in the other cases,
isomers were produced in equal amounts.
In relation to tetrazoles 4, it was shown that the re-
placement of the potassium cation by triethylammonium
had little effect on the yields of the corresponding isomers
and their ratio in the reactions of 4 with iodomethane,
chloroacetonitrile, and 1-chloromethoxy-3,3-dimethyl-
1-triazene 2-oxide (see Table 1).
Experimental
The course of the reactions was monitored by TLC on Silufol
UV-254 plates. The reaction products were isolated by prepara-
tive TLC on UV-254 silica gel. The IR spectra were measured
on a Bruker ALPHA-T spectrometer. The NMR spectra were
recorded on a Bruker AM-300 spectrometer in CDCl3. High-
resolution electrospray ionization mass spectra were obtained on
a Bruker micrOTOF II mass spectrometer. The melting points
were measured on a Boetius hot-stage apparatus. Tetrazoles
1—410 and 1-chloromethoxy-3,3-dimethyl-1-triazene 2-oxide11
were synthesized according to procedures described previously.
Reaction of tetrazole salts 1 with iodomethane. A solution of
AgNO3 (0.18 g, 1.1 mmol) was added to a solution of 1 (0.2 g,
1.07 mmol) in distilled water (3 mL). The precipitate that formed
was filtered off, successively washed with water (5 mL), acetone
(5 mL), and diethyl ester (5 mL), dried, and placed in a reaction
flask. Then acetonitrile (5 mL) and MeI (0.18 g, 1.26 mmol)
were added to the reaction mixture, and the mixture was stirred
in the dark for 72 h at ~20 °C. The precipitate was filtered off
and washed with acetonitrile. The filtrate was concentrated.
Compounds 5a and 9a were isolated from the residue by TLC
using CHCl3—methanol (20 : 1) as the eluent.
To summarize, it was shown that the alkylation of
5-(3,3-substituted-2-oxido-1-triazeneoxymethyl)tetra-
zoles with iodomethane, dimethyl sulfate, chloroaceto-
nitrile, and 1-chloromethoxy-3,3-dimethyl-1-triazene
2-oxide affords mainly two corresponding isomers at
positions 1 and 2 of the tetrazole ring with low selectiv-
ity. The cation and solvent were found to have an in-
significant effect on the selectivity of the reaction. The
structures of compounds 5—12 were established by
NMR and IR spectroscopy and mass spectrometry. The
conclusion about the positions of substituents at the
nitrogen atoms of tetrazole was drawn based on the
3,3-Dimethyl-1-[(1-methyl-1H-tetrazol-5-yl)methoxy]-1-
triazene 2-oxide (5a). The yield was 0.075 g (35%), m.p. 49—51 °C
(hexane—Et2O), Rf = 0.26. 1H NMR (CDCl3), δ: 3.00 (s, 6 H,
CH3N); 4.14 (s, 3 H, CH3N); 5.49 (s, 2 H, OCH2C). 13C NMR
(CDCl3), δ: 34.37, 42.15, 62.72, 150.65. IR, ν/cm–1: 3019, 2969,
2905, 2872, 1498, 1469, 1269, 1227, 1135, 1102, 1061, 1038,
1014, 945, 807, 665. ESI-MS, found m/z: 202.1051 [M + H]+,
1
previously established fact that the H NMR spectra
show signals of methyl and methylene groups at the
nitrogen atom N(2) at lower field compared to those at

Smirnov and Gordeev
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Russ. Chem. Bull., Int. Ed., Vol. 69, No. 11, November, 2020
219.1312 [M + NH4]+, 224.0871 [M + Na]+, 240.0607 [M + K]+;
calculated for C5H11N7O2 202.1047 [M + H]+, 219.1312
[M + NH4]+, 224.0866 [M + Na]+, 240.0606 [M + K]+.
3,3-Dimethyl-1-[(2-methyl-2H-tetrazol-5-yl)methoxy]-1-
triazene 2-oxide (9a). The yield was 0.038 g (18%), m.p. 33—36 °C
(hexane—Et2O), Rf = 0.42. 1H NMR (CDCl3), δ: 2.99 (s, 6 H,
CH3N); 4.34 (s, 3 H, CH3N); 5.41 (s, 2 H, OCH2C). 13C NMR
(CDCl3), δ: 39.63, 42.62, 65.14, 161.84. IR, ν/cm–1: 2917, 1499,
1454, 1262, 1140, 1038, 1011, 947. ESI-MS, found m/z: 202.1047
[M + H]+, 219.1310 [M + NH4]+, 224.0861 [M + Na]+, 240.0599
[M + K]+; calculated for C5H11N7O2 202.1047 [M + H]+,
219.1312 [M + NH4]+, 224.0866 [M + Na]+, 240.0606 [M + K]+.
Alkylation of tetrazoles 1—4 (general procedure). Potassium
hydroxide (0.06 g, 1,1 mmol) was added to a solution of tetrazole
1—4 (1.1 mmol) in CH3OH (2 mL). The resulting solution was
stirred for 5 min, and the solvent was removed by evaporation.
Then CH3CN (40 mL) and the alkylating agent (1.1 mmol) were
added. The mixture was stirred for 4 h at 60—70 °C, the solution
was concentrated, and the products were isolated from the resi-
due by preparative TLC.
1-[(1-Cyanomethyl-1H-tetrazol-5-yl)methoxy]-3,3-dimeth-
yl-1-triazene 2-oxide (5b). Et2O as the eluent, Rf = 0.23, the yield
was 0.04 g (16%), m.p. 48—50 °C (hexane—Et2O). 1H NMR
(CDCl3), δ: 3.07 (s, 6 H, NCH3); 5.61 (s, 2 H, CH2N); 5.65
(s, 2 H, OCH2C). 13C NMR (CDCl3), δ: 35.76, 41.30, 63.40,
111.65, 150.87. IR, ν/cm–1: 2991, 2953, 1496, 1455, 1357, 1267,
1137, 1085, 1017, 946. ESI-MS, found m/z: 227.1008 [M + H]+,
249.0826 [M + Na]+, 265.0565 [M + K]+; calculated for
C6H10N8O2 227.0999 [M + H]+, 249.0819 [M + Na]+, 265.0558
[M + K]+.
lated for C8H14N8O2 255.1312 [M + H]+, 272.1578 [M + NH4]+,
277.1132 [M + Na]+, 293.0871 [M + K]+.
5-(3,3-Diethyl-2-oxido-1-triazeneoxymethyl)-1-(3,3-dime-
thyl-2-oxido-1-triazeneoxymethyl)-1H-tetrazole (6c). Et2O as
the eluent, Rf = 0.21, the yield was 0.069 g (19%), oil. 1H NMR
(CDCl3), δ: 1.06 (t, 6 H, CH3, J = 7.0 Hz); 3.07 (s, 6 H, CH3);
3.23 (q, 4 H, CH2, J = 7.0 Hz); 5.67 (s, 2 H, OCH2C); 6.44
(s, 2 H, OCH2N). IR, ν/cm–1: 2962, 2927, 2856, 1503, 1460,
1384, 1344, 1239, 1179, 1142, 1072, 1018. ESI-MS, found m/z:
333.1736 [M + H]+, 350.1999 [M + NH4]+, 355.1555 [M + Na]+,
371.1292 [M + K]+; calculated for C9H20N10O4 333.1742
[M + H]+; 350.2007 [M + NH4]+, 355.1561 [M + Na]+, 371.1301
[M + K]+.
1-(1-Methyl-1H-tetrazol-5-yl)methoxy-2-(pyrrolidino)di-
azene 2-oxide (7a). Et2O as the eluent, Rf = 0.22; MeI as the
alkylating agent, the yield was 0.125 g (50%), m.p. 79—81 °C
(Et2O—hexane). 1H NMR (CDCl3), δ: 1.86 (t, 4 H, CH2,
J = 6.5 Hz); 3.43 (t, 4 H, NCH2, J = 6.5 Hz); 4.08 (s, 3 H, CH3);
5.38 (s, 2 H, OCH2C). 13C NMR (CDCl3), δ: 22.96, 34.38,
50.58, 62.44, 150.86. IR, ν/cm–1: 2982, 2875, 1476, 1283, 1010.
ESI-MS, found m/z: 228.1207 [M + H]+, 245.1468 [M + NH4]+,
250.1023 [M + Na]+, 266.0765 [M + K]+; calculated for
C7H13N7O2 228.1203 [M + H]+, 245.1469 [M + NH4]+, 250.1023
[M + Na]+, 266.0762 [M + K]+.
1-(1-Cyanomethyl-1H-tetrazol-5-yl)-2-(pyrrolidino)meth-
oxydiazene 2-oxide (7b). Et2O as the eluent, Rf = 0.4, the yield
was 0.125 g (45%), m.p. 114—117 °C (Et2O). 1H NMR (CDCl3),
δ: 1.94 (t, 4 H, CH2, J = 6.5 Hz); 3.53 (t, 4 H, NCH2, J = 6.5 Hz);
5.60 (s, 2 H, CH2N); 5.64 (s, 2 H, OCH2C). 13C NMR (CDCl3),
δ: 23.10, 35.80, 50.53, 63.19, 111.97, 151.27. IR, ν/cm–1: 2995,
2960, 2880, 1460, 1292, 1091, 1015. ESI-MS, found m/z:
253.1151 [M + H]+, 270.1416 [M + NH4]+, 275.0969 [M + Na]+,
291.0711 [M + K]+; calculated for C8H12N8O2 253.1156 [M + H]+;
270.1421 [M + NH4]+; 275.0975 [M + Na]+, 291.0715 [M + K]+.
1-(3,3-Dimethyl-2-oxido-1-triazeneoxymethyl)-5-(2-pyr-
rolidino-2-oxido-1-diazeneoxymethyl)-1H-tetrazole (7c).
CHCl3—hexane—acetone (5 : 4 : 1) as the eluent, Rf = 0.21, the
yield was 0.078 g (22%), m.p. 98—101 °C (Et2O). 1H NMR
(CDCl3), δ: 1.93 (t, 4 H, CH2, J = 6.5 Hz); 3.04 (s, 6 H, CH3);
3.51 (t, 4 H, NCH2, J = 6.5 Hz); 5.57 (s, 2 H, OCH2C); 6.43
(s, 2 H, OCH2N). 13C NMR (CDCl3), δ: 22.99, 41.92, 50.50,
62.63, 75.97, 151.42. IR, ν/cm–1: 3426, 2970, 1482, 1276, 1037,
1008, 945. ESI-MS, found m/z: 331.1583 [M + H]+; 348.1853
[M + NH4]+; 353.1405 [M + Na]+, 369.1142 [M + K]+; calcu-
lated for C9H18N10O4 331.1585 [M + H]+, 348.1851 [M + NH4]+,
353.1405 [M + Na]+, 369.1144 [M + K]+.
1-(1-Methyl-1H-tetrazol-5-yl)methoxy-2-morpholinodiazene
2-oxide (8a). CHCl3—methanol (20 : 1) as the eluent, Rf = 0.22;
MeI as the alkylating agent, the yield was 0.082 g (31%); Me2SO4
as the alkylating agent, the yield was 0.056 g (24%), m.p.
86—88 °C (CHCl3—hexane). 1H NMR (CDCl3), δ: 3.40 (t, 4 H,
CH2N, J = 4.5 Hz); 3.79 (t, 4 H, OCH2, J = 4.5 Hz); 4.15 (s, 3 H,
NCH3); 5.51 (s, 2 H, OCH2C). 13C NMR (CDCl3), δ: 35.85,
51.15, 59.84, 62.85, 150.51. IR, ν/cm–1: 3011, 2965, 2875, 1497,
1468, 1273, 1224, 1109, 1045, 1017, 952, 876, 814, 707, 659.
ESI-MS, found m/z: 244.1147 [M + H]+, 261.1406 [M + NH4]+,
266.0963 [M + Na]+, 282.0699 [M + K]+; calculated for
C7H13N7O3 244.1153 [M + H]+, 261.1418 [M + NH4]+, 266.0972
[M + Na]+, 282.0711 [M + K]+.
1,5-Bis(3,3-dimethyl-2-oxido-1-triazeneoxymethyl)-1H-tetr-
azole (5c). CHCl3—hexane—acetone (5 : 4 : 1) as the eluent,
Rf = 0.23, the yield was 0.107 g (32%), m.p. 72—75 °C (hexane—
1
Et2O). H NMR (CDCl3), δ: 2.98 (s, 6 H, CH3); 2.99 (s, 6 H,
CH3); 5.57 (s, 2 H, OCH2C); 6.37 (s, 2 H, OCH2N). 13C NMR
(CDCl3), δ: 41.78, 41.94, 62.65, 75.87, 151.15. IR, ν/cm–1: 3034,
2981, 2912, 1497, 1268, 1039, 946. ESI-MS, found m/z 305.1428
[M + H]+, 322.1685 [M + NH4]+, 327.1247 [M + Na]+, 343.0976
[M + K]+; calculated for C7H16N10O4 305.1429 [M + H]+;
322.1694 [M + NH4]+, 327.1248 [M + Na]+, 343.0988 [M + K]+.
3,3-Diethyl-1-[(1-methyl-1H-tetrazol-5-yl)methoxy]-1-tri-
azene 2-oxide (6a). Et2O as the eluent, Rf = 0.23; MeI as the
alkylating agent, the yield was 0.04 g (16%); Me2SO4 as the
alkylating agent, the yield was 0.019 g (7.5%), oil. 1H NMR
(CDCl3), δ: 1.03 (t, 6 H, CH3, J = 7.0 Hz); 3.20 (q, 4 H, CH2,
J =7.0 Hz); 4.16 (s, 3 H, CH3N); 5.55 (s, 2 H, OCH2C).
13C NMR (CDCl3), δ: 10.74, 33.83, 47.09, 62.31, 150.67. IR,
ν/cm–1: 2980, 2940, 2877, 1513, 1498, 1384, 1245, 1063, 1009.
ESI-MS, found m/z: 230.1358 [M + H]+, 247.1623 [M + NH4]+,
252.1174 [M + Na]+, 268.0914 [M + K]+; calculated for
C7H15N7O2 230.1360 [M + H]+; 247.1625 [M + NH4]+, 252.1179
[M + Na]+, 268.0919 [M + K]+.
1-[(1-Cyanomethyl-1H-tetrazol-5-yl)methoxy]-3,3-diethyl-
1-triazene 2-oxide (6b). Et2O as the eluent, Rf = 0.2, the yield
was 0.047 g (17%), m.p. 39—42 °C (hexane—Et2O). 1H NMR
(CDCl3), δ: 1.10 (t, 6 H, CH3, J = 7.0 Hz); 3.33 (q, 4 H, CH2,
J = 7.0 Hz); 5.61 (s, 2 H, CH2N); 5.68 (s, 2 H, OCH2C).
13C NMR (CDCl3), δ: 11.46, 39.59, 48.47, 65.42, 111.72, 161.75.
IR, ν/cm–1: 2964, 2930, 2875, 1490, 1458, 1380, 1246, 1080,
1013. ESI-MS, found m/z: 255.1310 [M + H]+, 272.1571
[M + NH4]+, 277.1124 [M + Na]+, 293.0867 [M + K]+; calcu-
1-(1-Cyanomethyl-1H-tetrazol-5-yl)-2-morpholinometh-
oxydiazene 2-oxide (8b). CHCl3—methanol (20 : 1) as the eluent,

5-(2-Oxido-1-triazeneoxymethyl)tetrazoles
Russ. Chem. Bull., Int. Ed., Vol. 69, No. 11, November, 2020
2157
Rf = 0.23, the yield was 0.067 g (23%). m.p. 101—102 °C
(CHCl3—hexane). 1H NMR (CDCl3), δ: 3.43 (t, 4 H, CH2N,
J = 4.9 Hz); 3.80 (t, 4 H, OCH2, J = 4.9 Hz); 5.58 (s, 2 H,
OCH2C); 5.66 (s, 2 H, NCH2CN). 13C NMR (CDCl3), δ: 35.83,
51.02, 63.43, 65.41, 111.75, 150.84. IR, ν/cm–1: 2991,
2956, 2932, 2867, 1502, 1459, 1366, 1270, 1231, 1113, 1090,
1024, 954, 952, 929, 873, 710, 562, 528. ESI-MS, found m/z:
269.1111 [M + H]+, 286.1371 [M + NH4]+, 291.0925 [M + Na]+,
307.0664 [M + K]+; calculated for C8H12N7O3 269.1105
[M + H]+, 286.1371 [M + NH4]+, 291.0925 [M + Na]+, 307.0664
[M + K]+.
1-(3,3-Dimethyl-2-oxido-1-triazeneoxymethyl)-5-(2-mor-
pholino-2-oxido-1-diazeneoxymethyl)-1H-tetrazole (8c).
CHCl3—methanol (20 : 1) as the eluent, Rf = 0.19, the yield was
0.094 g (25%), m.p. 93—95 °C (CHCl3—hexane). 1H NMR
(CDCl3), δ: 3.02 (s, 6 H, CH3); 3.39 (t, 4 H, CH2N, J = 4.7 Hz);
3.77 (t, 4 H, OCH2, J = 4.7 Hz); 5.61 (s, 2 H, OCH2C); 6.37
(s, 2 H, NCH2O). 13C NMR (CDCl3), δ: 41.89, 51.09, 62.95,
65.48, 76.00, 151.08. IR, ν/cm–1: 2968, 2928, 2865, 1504, 1452,
1366, 1272, 229, 1102, 1060, 1026, 976, 945, 868, 803, 739, 686,
547. ESI-MS, found m/z: 347.1533 [M + H]+; 364.1798
[M + NH4]+; 369.1349 [M + Na]+, 385.1090 [M + K]+; calcu-
lated for C9H18N10O5 347.1534 [M + H]+, 364.1800 [M + NH4]+,
369.1354 [M + Na]+, 385.1093 [M + K]+.
1-[(2-Cyanomethyl-2H-tetrazol-5-yl)methoxy]-3,3-diethyl-
1-triazene 2-oxide (10b). Et2O as the eluent, Rf = 0.46, the yield
was 0.095 g (34%), oil. 1H NMR (CDCl3), δ: 1.10 (t, 6 H, CH3,
J = 7.0 Hz); 3.18 (q, 4 H, CH2, J = 7.0 Hz); 5.60 (s, 2 H,
OCH2C); 5.67 (s, 2 H, CH2N). 13C NMR (CDCl3), δ: 11.44,
40.14, 48.35, 65.02, 111.27, 163.22. IR, ν/cm–1: 2982, 2941,
2877, 1514, 1451, 1369, 1242, 1062, 1008. ESI-MS, found m/z:
255.1311 [M + H]+, 272.1574 [M + NH4]+, 277.1127 [M + Na]+,
293.0862 [M + K]+; calculated for C8H14N8O2 255.1312 [M + H]+,
272.1578 [M + NH4]+, 277.1132 [M + Na]+, 293.0871 [M + K]+.
5-(3,3-Diethyl-2-oxido-1-triazeneoxymethyl)-2-(3,3-di-
methyl-2-oxido-1-triazeneoxymethyl)-2H-tetrazole (10c). Et2O
as the eluent, Rf = 0.4, the yield was 0.069 g (19%), oil. 1H NMR
(CDCl3), δ: 1.08 (t, 6 H, CH3, J = 7.0 Hz); 3.08 (s, 6 H, CH3);
3.15 (q, 4 H, CH2, J = 7.0 Hz); 5.56 (s, 2 H, OCH2C); 6.42
(s, 2 H, OCH2N). IR, ν/cm–1: 2964, 2927, 2858, 1504, 1460,
1386, 1344, 1239, 1182, 1141, 1077, 1013. ESI-MS, found m/z:
333.1736 [M + H]+, 350.2003 [M + NH4]+, 355.1556 [M + Na]+,
371.1294 [M + K]+; calculated for C9H20N10O4 333.1742
[M + H]+, 350.2007 [M + NH4]+, 355.1561 [M + Na]+, 371.1301
[M + K]+.
1-(2-Methyl-2H-tetrazol-5-yl)methoxy-2-(pyrrolidino)di-
azene 2-oxide (11a). Et2O as the eluent, Rf = 0.41; MeI as the
alkylating agent, the yield was 0.085 g (34%); Me2SO4 as the
alkylating agent, the yield was 0.105 g (42%), m.p. 58—61 °C.
1H NMR (CDCl3), δ: 1.89 (t, 4 H, CH2, J = 6.5 Hz); 3.50 (t, 4 H,
NCH2, J = 6.5 Hz); 4.32 (s, 3 H, CH3); 5.36 (s, 2 H, OCH2C).
13C NMR (CDCl3), δ: 22.87, 39.56, 50.81, 64.87, 162.00. IR,
ν/cm–1: 2960, 2881, 1484, 1276, 1010. ESI-MS, found m/z:
228.1202 [M + H]+, 245.1468 [M + NH4]+, 250.1023 [M + Na]+,
266.0762 [M + K]+; calculated for C7H13N7O2 228.1203
[M + H]+, 245.1469 [M + NH4]+, 250.1023 [M + Na]+, 266.0762
[M + K]+.
1-(2-Cyanomethyl-2H-tetrazol-5-yl)-2-(pyrrolidino)meth-
oxydiazene 2-oxide (11b). Et2O as the eluent, Rf = 0.4, the yield
was 0.055 g (20%), m.p. 39—42 °C (hexane—Et2O). 1H NMR
(CDCl3), δ: 1.93 (t, 4 H, CH2, J = 6.5 Hz); 3.53 (t, 4 H, NCH2,
J = 6.5 Hz); 5.43 (s, 2 H, CH2N); 5.66 (s, 2 H, OCH2C).
13C NMR (CDCl3), δ: 22.94, 40.32, 50.82, 64.62, 111.33, 163.27.
IR, ν/cm–1: 2984, 2956, 2882, 1484, 1280, 1087, 1009. ESI-MS,
found m/z: 253.1157 [M + H]+, 270.1419 [M + NH4]+, 275.0971
[M + Na]+, 291.0710 [M + K]+; calculated for C8H12N8O2
253.1156 [M + H]+, 270.1421 [M + NH4]+, 275.0975 [M + Na]+,
291.0715 [M + K]+.
2-(3,3-Dimethyl-2-oxido-1-triazeneoxymethyl)-5-(2-pyr-
rolidino-2-oxido-1-diazeneoxymethyl)-2H-tetrazole (11c).
CHCl3—hexane—acetone (5 : 4 : 1) as the eluent, Rf = 0.42, the
yield was 0.078 g (22%), m.p. 57—59 °C (Et2O). 1H NMR
(CDCl3), δ: 1.91 (t, 4 H, CH2, J = 6.5 Hz); 3.05 (s, 6 H, CH3);
3.51 (t, 4 H, NCH2, J = 6.5 Hz); 5.42 (s, 2 H, OCH2C); 6.41
(s, 2 H, OCH2N). 13C NMR (CDCl3), δ: 22.85, 41.98, 50.76,
64.73, 79.86, 162.73. IR, ν/cm–1: 3500, 2981, 2880, 1496, 1271,
1082, 1018, 945. ESI-MS, found m/z: 331.1583 [M + H]+,
348.1853 [M + NH4]+, 353.1403 [M + Na]+, 369,1140 [M + K]+;
calculated for C9H18N10O4 331.1585 [M + H]+, 348.1851
[M + NH4]+, 353.1405 [M + Na]+, 369.1144 [M + K]+.
1-(2-Methyl-2H-tetrazol-5-yl)methoxy-2-morpholinodiazene
2-oxide (12a), CHCl3—methanol (20 : 1) as the eluent, Rf = 0.4;
MeI as the alkylating agent, the yield was 0.085 g (32%); Me2SO4
as the alkylating agent, the yield was 0.082 g (35%), m.p.
75—77 °C (CHCl3—hexane). 1H NMR (CDCl3), δ: 3.40 (t, 4 H,
3,3-Dimethyl-1-[(2-methyl-2H-tetrazol-5-yl)methoxy]-1-
triazene 2-oxide (9a). CHCl3—hexane—acetone (5 : 4 : 1) as the
eluent, Rf = 0.42; MeI as the alkylating agent, the yield was
0.069 g (31%); Me2SO4 as the alkylating agent, the yield was
0.082 g (37%), identical to that reported above.
1-[(2-Cyanomethyl-2H-tetrazol-5-yl)methoxy]-3,3-dimeth-
yl-1-triazene 2-oxide (9b). Et2O as the eluent, Rf = 0.5, the yield
was 0.037 g (15%), m.p. 48—49 °C (hexane—Et2O). 1H NMR
(CDCl3), δ: 3.03 (s, 6 H, NCH3); 5.48 (s, 2 H, CH2N); 5.67
(s, 2 H, OCH2C). 13C NMR (CDCl3), δ: 40.26, 42.46, 64.76,
111.20, 162.02. IR, ν/cm–1: 2990, 2950, 1498, 1454, 1368, 1263,
1141, 1032, 1011, 949. ESI-MS, found m/z: 227.1008 [M + H]+;
244.1273 [M + NH4]+; 249.0825 [M + Na]+, 265.0564 [M + K]+;
calculated for C6H10N8O2 227.0999 [M + H]+, 244.1265
[M + NH4]+, 249.0819 [M + Na]+, 265.0558 [M + K]+.
2,5-Bis(3,3-dimethyl-2-oxido-1-triazeneoxymethyl)-2H-tetr-
azole (9c). CHCl3—hexane—acetone (5 : 4 : 1) as the eluent,
Rf = 0.41, the yield was 0.104 g (31%), m.p. 41—44 °C (hexane—
1
Et2O). H NMR (CDCl3), δ: 2.95 (s, 6 H, CH3); 3.00 (s, 6 H,
CH3); 5.41 (s, 2 H, OCH2C); 6.38 (s, 2 H, OCH2N). 13C NMR
(CDCl3), δ: 41.84, 42.34, 64.84, 79.82, 162.39. IR, ν/cm–1: 2983,
2918, 1500, 1265, 1072, 1016, 945. ESI-MS, found m/z: 305.1430
[M + H]+, 322.1689 [M + NH4]+, 327.1247 [M + Na]+, 343.0973
[M + K]+; calculated for C7H16N10O4 305.1429 [M + H]+,
322.1694 [M + NH4]+, 327.1248 [M + Na]+, 343.0988 [M + K]+.
3,3-Diethyl-1-[(2-methyl-2H-tetrazol-5-yl)methoxy]-1-tri-
azene 2-oxide (10a). Et2O as the eluent, Rf = 0.4; MeI as the
alkylating agent, the yield was 0.065 g (26%); Me2SO4 as the
alkylating agent, the yield was 0.10 g (40%), m.p. 14—16 °C
(Et2O—hexane). 1H NMR (CDCl3), δ: 1.06 (t, 6 H, CH3,
J = 7.0 Hz); 3.12 (q, 4 H, CH2, J = 7.0 Hz); 4.34 (s, 3 H, CH3N);
5.49 (s, 2 H, OCH2C). 13C NMR (CDCl3), δ: 11.26, 39.38,
48.26, 65.23, 161.56. IR, ν/cm–1: 2980, 2940, 2877, 1514, 1433,
1385, 1241, 1062, 1008. ESI-MS, found m/z: 230.1362 [M + H]+,
247.1627 [M + NH4]+, 252.1180 [M + Na]+, 268.0919 [M + K]+;
calculated for C7H15N7O2 230.1360 [M + H]+, 247.1625
[M + NH4]+, 252.1179 [M + Na]+, 268.0919 [M + K]+.

Smirnov and Gordeev
2158
Russ. Chem. Bull., Int. Ed., Vol. 69, No. 11, November, 2020
CH2N, J = 4.6 Hz); 3.79 (t, 4 H, OCH2, J = 4.6 Hz); 4.34 (s, 3 H,
NCH3); 5.45 (s, 2 H, OCH2C). 13C NMR (CDCl3), δ: 39.07
(CH3N); 50.95 (CH2N); 64.75 (CCH2O); 65.10 (CH2O); 161.18
(C). IR, ν/cm–1: 3042, 2976, 2864, 1497, 1457, 1365, 1274, 1115,
1037, 1012, 981, 958, 874, 814. Found (%): C, 34.45; H, 5.41;
N, 39.83. C7H13N7O3. Calculated (%): C, 34.57; H, 5.39;
N, 40.31.
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oxydiazene 2-oxide (12b). CHCl3—methanol (20 : 1) as the elu-
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(hexane—Et2O). 1H NMR (CDCl3), δ: 3.41 (t, 4 H, CH2N,
J = 4.9 Hz); 3.80 (t, 4 H, OCH2, J = 4.9 Hz); 5.47 (s, 2 H,
OCH2C); 5.66 (s, 2 H, NCH2CN). 13C NMR (CDCl3), δ: 40.31
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111.25 (CN); 162.86 (C). IR, ν/cm–1: 2959, 2932, 2864, 1500,
1458, 1366, 1270, 1229, 1112, 1087, 1027, 1009, 954, 929, 872,
818, 708, 562. ESI-MS, found m/z: 269.1105 [M + H]+, 286.1367
[M + NH4]+, 291.0921 [M + Na]+, 307.0659 [M + K]+; calcu-
lated for C8H12N7O3 269.1105 [M + H]+; 286.1371 [M + NH4]+,
291.0925 [M + Na]+, 307.0664 [M + K]+.
2-(3,3-Dimethyl-2-oxido-1-triazeneoxymethyl)-5-(2-mor-
pholino-2-oxido-1-diazeneoxymethyl)-2H-tetrazole (12c).
CHCl3—methanol (20 : 1) as the eluent, Rf = 0.38, the yield was
0.071 g (19%), m.p. 101—102 °C (CHCl3—hexane). 1H NMR
(CDCl3), δ: 3.07 (s, 6 H, CH3); 3.40 (t, 4 H, CH2N, J = 4.7 Hz);
3.80 (t, 4 H, OCH2, J = 4.7 Hz); 5.47 (s, 2 H, OCH2C); 6.41
(s, 2 H, NCH2O). 13C NMR (CDCl3), δ: 42.00, 51.43, 65.12,
65.60, 79.91, 162.44. IR, ν/cm–1: 2980, 2924, 2864, 1502, 1461,
1344, 1269, 1229, 1183,1110, 1082, 1013, 976, 949, 871, 815, 762,
685, 595, 523. ESI-MS, found m/z: 347.1533 [M + H]+, 364.1797
[M + NH4]+, 369.1344 [M + Na]+, 385.1091 [M + K]+; calcu-
lated for C9H18N10O5 347.1534 [M + H]+, 364.1800 [M + NH4]+,
369.1354 [M + Na]+, 385.1093 [M + K]+.
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1-Methyl-1H-tetrazole13 (13). The yield was 0.006 g (7%),
m.p. 36—37 °C (Et2O). 1H NMR (CDCl3), δ: 4.11 (s, 3 H,
NCH3); 8.65 (s, 1 H, CH). 13C NMR (CDCl3), δ: 33.86; 142.63.
Alkylation of tetrazole 4 in the presence of triethylamine.
Triethylamine (0.14 mL, 1.0 mmol) was added to a suspension
of tetrazole 4 (0.23 g, 1.0 mmol) in acetonitrile (10 mL). The
mixture was stirred for 10 min at ~20 °C. Then iodomethane,
chloroacetonitrile, or 1-chloromethoxy-3,3-dimethyl-1-triazene
2-oxide (1.0 mmol) was added. The reaction mixture was warmed
to 50 °C and stirred for 6 h at this temperature. The solvent was
removed, CHCl3 (10 mL) was added to the residue, and the
precipitate was filtered off. The following products, which
are identical to those described above, were isolated from the
filtrate by TLC: 8a, 36%; 8b, 24%; 8c, 22%; 12a, 36%; 12b, 28%;
12c, 21%.
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Received January 21, 2020;
in revised form February 7, 2020;
accepted March 16, 2020