Synthesis and Characterization of Sodium 5-Chlorotetrazolate Dihydrate by Chlorination of 1H-Tetrazole

Article abstract of DOI:10.1002/zaac.201400486

A convenient, simple work-up procedure and low-cost chlorination method was developed to prepare sodium 5-chlorotetrazolate dihydrate by chlorination of self-prepared 1H-tetrazole with sodium hypochlorite solution. Several organic extracting solvents and factors (raw material ratio, reaction temperature, and reaction time) were investigated to optimize the operating conditions of the chlorination procedure. These products were characterized by ¹H and ¹³C NMR spectroscopy, vibrational spectroscopy (IR), mass spectroscopy (MS), and single-crystal X-ray diffraction. In addition, the thermal behaviors of the resulting sodium 5-chlorotetrazolate dihydrate and sodium tetrazolate monohydrate were investigated and compared by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG). The results indicated that the optimum chlorination conditions were a stoichiometric raw materials ratio of 1:12:12 (1H-tetralzole: sodium hypochlorite solution : acetic acid solution), a reaction temperature of 55°C, a reaction time of 6 h, affording a 92.76% yield; moreover, acetone was determined to be the best extraction solvent in terms of yield and toxicity. Crystal data: sodium tetrazolate, orthorhombic, Pmc2(1), a = 5.847(4), b = 5.605(3), c = 6.387(4) ?, V = 209.3(2) ?³, Z = 2, ρ = 1.746 Mg·m^-3; sodium 5-chlorotetrazolate, orthorhombic, Pnma, a = 6.8611(19), b = 6.9243(19), c = 12.281(4) ?, V = 583.5(3) ?³, Z = 8, ρ = 1.850 Mg·m^-3. Sodium tetrazolate has a melting point at 275.97°C and an exothermic decomposition peak at 319.45°C, whereas sodium 5-chlorotetrazolate shows only a sharp exothermic peak at 237.33°C due to violent decomposition without melting.

Full text of DOI:10.1002/zaac.201400486

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ARTICLE
DOI: 10.1002/zaac.201400486
Synthesis and Characterization of Sodium 5-Chlorotetrazolate Dihydrate by
Chlorination of 1H-Tetrazole
Xiaojun Wang,[a] Jiping Liu,*[a] Dong Wang,[a] Xiaolu Bi,[a] and Wei Zhao[a]
Keywords: Heterocycles; Tetrazole derivative; Chlorination; Halogenation
Abstract. A convenient, simple work-up procedure and low-cost chlo-
rination method was developed to prepare sodium 5-chlorotetrazolate
dihydrate by chlorination of self-prepared 1H-tetrazole with sodium
chiometric raw materials ratio of 1:12:12 (1H-tetralzole : sodium hypo-
chlorite solution : acetic acid solution), a reaction temperature of
55 °C, a reaction time of 6 h, affording a 92.76% yield; moreover,
hypochlorite solution. Several organic extracting solvents and factors acetone was determined to be the best extraction solvent in terms of
(raw material ratio, reaction temperature, and reaction time) were in- yield and toxicity. Crystal data: sodium tetrazolate, orthorhombic,
vestigated to optimize the operating conditions of the chlorination pro-
Pmc2(1), a = 5.847(4), b = 5.605(3), c = 6.387(4) Å, V = 209.3(2) Å3,
Z = 2, ρ = 1.746 Mg·m–3; sodium 5-chlorotetrazolate, orthorhombic,
Pnma, a = 6.8611(19), b = 6.9243(19), c = 12.281(4) Å, V =
583.5(3) Å3, Z = 8, ρ = 1.850 Mg·m–3. Sodium tetrazolate has a melt-
ing point at 275.97 °C and an exothermic decomposition peak at
319.45 °C, whereas sodium 5-chlorotetrazolate shows only a sharp
exothermic peak at 237.33 °C due to violent decomposition without
melting.
1
cedure. These products were characterized by H and 13C NMR spec-
troscopy, vibrational spectroscopy (IR), mass spectroscopy (MS), and
single-crystal X-ray diffraction. In addition, the thermal behaviors of
the resulting sodium 5-chlorotetrazolate dihydrate and sodium tetrazol-
ate monohydrate were investigated and compared by differential scan-
ning calorimetry (DSC) and thermogravimetric analysis (TG). The re-
sults indicated that the optimum chlorination conditions were a stoi-
tetrazole derivatives with sodium nitrite and cuprous halides[13]
(Scheme 2); (3) direct halogenation of tetrazole derivatives by
elemental halogen, NBS or NCS[8,9,14] (Scheme 3); (4) haloge-
nating reaction of nitro compounds[15,16] (Scheme 4). How-
ever, the four approaches suffer from drawbacks such as high
toxicity, high raw materials cost, a complex reaction pro-
cedure, harsh reaction conditions, and the formation of sensi-
tive intermediates and by-products that are difficult to separate.
Introduction
Tetrazoles are a special class of five-membered heterocyclic
compounds with many C–N, N–N, and N=N bonds that pos-
sess excellent thermal stability, high density and enthalpy of
formation, good chemical reactivity, which have attracted great
interest as pharmaceuticals,[1–3] photographic materials,[4]
polydentate linker,[5,6] and energy materials.[7] The halogenat-
ing reaction of tetrazoles is of utmost importance for increas-
ing the activity and halogen compounds are promising chemi-
cal intermediates for synthesizing many excellent materials
that are used in medicines, agricultural agents, and even energy
materials.[8,9]
To date, the traditional methods for introducing halogen ele-
ments have included the following: (1) the [3+2] dipolar cyclo-
addition of dichloroisocyanide compounds with sodium Scheme 2. Sandmeyer reaction of amino tetrazole derivatives.
azide[10–12] (Scheme 1); (2) Sandmeyer reaction of amino
Scheme 1. [3+2] Dipolar cycloaddition of dichloroisocyanide com-
pounds.
Scheme 3. Direct halogenation of elemental halogen, NBS or NCS.
* Prof. J. Liu
Fax: +86-010-68914530
E-Mail: liujp@bit.edu.cn
[a] School of Materials Science & Engineering
Beijing Institute of Technology
5 South Zhongguancun Street, Haidian District
Beijing 100081, P.R. China
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/zaac.201400486 or from the au-
thor.
Scheme 4. Halogenating reaction of nitro compounds.
Z. Anorg. Allg. Chem. 0000, ᭿,(᭿), 0–0
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X. Wang, J. Liu, D. Wang, X. Bi, W. Zhao
ARTICLE
Table 1. The extraction effect of eight organic solvents.
Solvent
Boiling point /°C
Polarity
Content of extract /g
Color
FT-IR spectrogram
Et2O
CH2Cl2
THF
34.6
39.8
66
78.4
77
56.05
81.1
64.5
2.9
3.4
4.2
4.3
4.3
5.4
6.2
6.6
–
–
–
–
–
–
0.03
0.36
0.01
0.05
0.05
0.62
yellow
white
white
white
yellow
white
Product
Mixture
Product
Product
Product
Mixture
EtOH
EtOAc
Acetone
Acetonitrile
MeOH
In this work, we developed a convenient, simple work-up analysis (R) confirming the degrees of influence of the various
process and low-cost chlorination protocol (Scheme 5) that can parameters were analyzed. The results showed that the reaction
address the shortcomings of the abovementioned methods for temperature and raw material ratio produced a greater effect
the formation of sodium 5-chlorotetrazolate dihydrate using on the yield than did the reaction time. Table 3 also thoroughly
1H-tetrazole as a raw material, sodium hypochlorite (NaClO) describes the effects of reaction temperatures on the yield at a
solution as a halogenating reagent and acetic acid as a solvent. raw material ratio of 1:12:12 and reaction time of 6 h and
Several organic extracting solvents and factors (raw material showed that 55 °C was the best reaction temperature because
ratio, reaction temperature, and reaction time) were investi- chlorine gas could escape rapidly at high temperature. In sum-
gated to optimize the operating conditions. At the same time, mary, the optimal reaction conditions were a raw material ratio
sodium tetrazolate and sodium 5-chlorotetrazolate were fully of 1:12:12, a reaction temperature of 55 °C, and a reaction
characterized with IR and NMR (1H, 13C) spectroscopy, mass time 6 h, affording a 92.76% yield.
spectroscopy (MS), differential scanning calorimetry (DSC),
thermogravimetric analysis (TG), and single-crystal X-ray dif-
fraction.
Table 2. Orthogonal design experiment of sodium 5-chlorotetrazolate
dihydrate.
Entry
Reaction tem-
perature /°C
Reaction time Molar ratio Yield /%
/h
1
2
3
4
5
6
7
8
9
25
25
25
35
35
35
45
45
6
8
12
6
8
12
6
8
1:3:3
1:6:6
1:12:12
1:6:6
1:12:12
1:3:3
1:12:12
1:3:3
1:6:6
35.853
63.137
77.147
38.77
14.90
59.06
91.95
82.92
57.76
31.13
81.73
61.53
47.43
Scheme 5. Chlorination of 1H-tetrazole with NaClO solution.
Results and Discussion
45
12
¯
K1
55.303
57.270
63.563
8.26
59.85
59.450
56.837
3.013
Process Optimization
¯
K2
¯
K3
Eight types of solvents (80 mL) were chosen to extract the
same amount of mixture containing sodium 5-chlorotetrazolate
dihydrate (0.80 g). The IR spectra and contents of filter and
extract were measured and analyzed. The experimental results
presented in Table 1 demonstrated the effect of extraction. It
should be noted that the weak polarity of the solvents (diethyl
ether and dichloromethane) adversely affected the extraction
procedure, whereas the strong polarity of the solvents (particu-
larly that of methyl alcohol) made it difficult to separate the
product from the inorganic salt. Ethanol also led to poor ex-
traction due to high solubility of the inorganic salt in ethanol.
The final compound could easily be isolated by extraction
using THF, ethyl acetate, acetone, and acetonitrile, among
which acetone was the best extraction solvent in terms of yield
and toxicity.
R
Table 3. The effect of reaction temperature on the yield.
Entry
Reaction temperature /°C
Yield /%
1
2
3
45
55
65
81.73
92.76
73.57
Crystal Structures
Single crystals of sodium 5-chlorotetrazolate and sodium
tetrazolate suitable for X-ray diffraction analysis were obtained
A orthogonal design experiment (Table 2) was carried out to by recrystallization from acetone and ethanol, respectively. Se-
test the effects of reaction temperature (25 °C, 35 °C, 45 °C), lected crystallographic data and parameters from X-ray collec-
reaction time (6 h, 8 h, 12 h) and raw material molar ratio (1H- tion and refinement for sodium 5-chlorotetrazolate and sodium
tetralzole: sodium hypochlorite solution: acetic acid solution = tetrazolate are summarized in Table 4. Sodium 5-chlorotet-
1:3:3, 1:6:6, 1:12:12) on the product yield. The average values razolate containing two crystal water, crystallizes in the ortho-
(K) associated with the optimal reaction conditions and range rhombic space group Pnma with a cell volume of 583.5(3) Å3,
¯
2
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Sodium 5-Chlorotetrazolate Dihydrate by Chlorination of 1H-Tetrazole
Table 4. Crystallographic data of sodium 5-chlorotetrazolate and sodium tetrazolate.
Sodium 5-chlorotetrazolate
Sodium tetrazolate
Empirical formula
C0.5H2Cl0.5N2Na0.5
81.26
O
CH3N4NaO
110.06
Formula weight /g·mol–1
Temperature /K
293(2)
153(2)
Wavelength /Å
θ range for data collection /°
Crystal system
Space group
0.71073
3.32 to 31.52
orthorhombic
Pnma
0.71073
3.48 to 31.52
orthorhombic
Pmc2(1)
a /Å
b /Å
c /Å
α /°
6.8611(19)
6.9243(19)
12.281(4)
90
5.847(4)
5.605(3)
6.387(4)
90
β /°
90
90
γ /°
90
583.5(3)
8
1.850
0.652
90
209.3(2)
2
1.746
0.230
112
Volume /Å3
Z
Calculated density /Mg·m–3
Absorption coefficient /mm–1
F(000)
328
Crystal size /mm
R(int)
0.48ϫ0.35ϫ0.28
0.0243
1.001
R1 = 0.0277, wR2 = 0.0773
R1 = 0.0283, wR2 = 0.0780
0.67ϫ0.20ϫ0.08
0.0311
1.002
R1 = 0.0302, wR2 = 0.0651
R1 = 0.0328, wR2 = 0.0666
Goodness-of-fit on F2
Final R indices [I Ͼ2σ (I)]
R indices (all data)
while sodium tetrazolate containing one crystal water, crys- Table 5. Selected bond lengths /Å and angles /° for sodium 5-chloro-
tetrazolate and sodium tetrazolate.
tallizes in the orthorhombic space group Pmc2(1) with a cell
volume of 209.3(2) Å3. The ORTEP plots of the two crystal
Sodium 5-chlorotetrazolate
Sodium tetrazolate
structures are shown in Figure 1. Selected bond lengths and
bond angles are listed in Table 5. The crystal structure of so-
dium 5-chlorotetrazolate dihydrate possesses laminar structure
with non-overlapping and each layer contains intersecting
channels viewed along c axis and b axis (Figure 2 and Fig-
ure 3).
Na1–O(1)2
Na–O(1Ј)
Na–N(4)3
N(1)–C(1)
N(1)–N(2)
N(2)–N(3)
N(3)–N(4)
C(1)–N(4)
C(1)–Cl(1)
Na–N(3Ј)
2.4211(9)
Na(1)4–O(1)
Na(1)–N(1)
Na(2)5–N(1)
N(1)–C(1)
N(1)–N(2)
N(2)–N(3)6
N(3)–N(4)
C(1)–N(4)
C(1)–H(1)
2.386(9)
2.536(6)
2.544(6)
1.3312(13)
1.3539(13)
1.3056(18)
1.3539(13)
1.3312(13)
0.9500
2.4107(10)
2.5665(14)
1.3286(16)
1.3520(17)
1.3173(15)
1.3499(17)
1.3269(17)
1.7018(14)
2.5494(14)
N(4)–Na–(O1)
N(4)–Na–O(1Ј)
Na–N(4)–N(3)
Na–N(4)–C(1)
C(1)–N(1)–N(2)
N(1)–N(2)–N(3)
N(2)–N(3)–N(4)
N(3)–N(4)–C(1)
N(4)–C(1)–N(1)
Cl(1)–C(1)–N(4)
Cl(1)–C(1)–N(1)
84.85(3)
77.13(3)
O(1)– Na(1)–N(1) 101.3(2)
Na(1)–N(1)–N(2) 122.1(4)
Na(1)–N(1)–C(1) 114.5(5)
122.64(8)
133.66(9)
103.69(10)
109.43(11)
109.66(11)
103.70(10)
113.52(12)
123.80(10)
122.67(10)
C(1)–N(1)–N(2)
N(1)–N(2)–N(3)
N(2)–N(3)–N(4)
N(3)–N(4)–C(1)
N(1)–C(1)–N(4)
H(1)–C(1)–N(1)
H(1)–C(1)–N(4)
104.13(9)
109.60(5)
109.60(5)
104.13(9)
112.52(14)
123.7
123.7
Figure 1. The ORTEP plots of the structures of crystal sodium 5-chlo-
rotetrazolate dihydrate (left) and sodium tetrazolate monohydrate
(right).
1
Symmetry transformations used to generate equivalent atoms: 1 –x,
2
3
4
0.5+y, –z + 1; –0.5+x, 1.5–y, 0.5–z; 0.5–x, 2 –y, –0.5+z; x, y, z;
5
6
2 –x, 1 –y, 0.5+z; 1 –x, y, z.
Thermal Behavior
The thermal behaviors of sodium 5-chlorotetrazolate dihy- melting at 275.97 °C and had an exothermic decomposition
drate and sodium tetrazolate monohydrate were investigated peak at 319.45 °C, whereas sodium 5-chlorotetrazolate dihy-
by TG/DSC at a heating rate of 10 °C·min–1 in the temperature drate only decomposed at 237.33 °C without melting; the two
range from 35–450 °C with an amount of 1.6088 mg and products released nitrogen in the stage of decomposition re-
3.4073 mg, respectively. The curves of TG and DSC are shown sulting in a shock for the specimen holder and an increase of
in Figure 4 and Figure 5.
weight, but sodium 5-chlorotetrazolate dihydrate produced
In the curves, it can be seen that the two products loose more gas and was more powerful than sodium tetrazolate
crystal water at 100 °C; sodium tetrazolate monohydrate was monohydrate. The result indicated that sodium 5-chlorotet-
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X. Wang, J. Liu, D. Wang, X. Bi, W. Zhao
ARTICLE
Figure 2. View along c axis in the structure of sodium 5-chlorotet-
razolate dihydrate.
Figure 5. DSC of sodium 5-chlorotetrazolate dihydrate (imaginary
line) and sodium tetrazolate monohydrate (full line) at a heating rate
of 10 °C·min–1.
Conclusions
A low-toxicity, convenient, simple work-up procedure and
low-cost method for producing sodium 5-chlorotetrazolate di-
hydrate by the chlorination of 1H-tetrazole was developed. By
optimizing the synthesis of sodium 5-chlorotetrazolate dehy-
drate, which is a stoichiometric ratio of raw materials of
1:12:12, a reaction temperature of 55 °C, a reaction time of 6
h, and acetone as the best extraction solvent in terms of yield
and toxicity, affording a 92.76% yield, the results obtained in
this study provide guidelines for the scaled-up halogenation of
tetrazole derivatives. Owing to its violent decomposition with-
out melting at 237.33 °C, sodium 5-chlorotetrazolate dihydrate
would be a moderately potential gas generating compound
with lower decomposition temperature compared with sodium
tetrazolate monohydrate and release of nitrogen.
Figure 3. View along b axis in the structure of sodium 5-chlorotet-
razolate dihydrate.
Experimental Section
General Methods: All other starting materials were of reagent quality
and were obtained from commercial sources without further purifica-
tion. Infrared spectra were recorded with a Bruker TENSOR 27 spec-
trophotometer (Germany) with KBr pellets in the 400–4000 cm–1 re-
gion. 1H NMR and 13C NMR spectra were recorded with a Bruker
Aspect ARX400 spectrometer at room temperature in [D6]DMSO solu-
tions with an internal TMS reference. Elemental analyses for carbon,
hydrogen, and nitrogen were performed with a Perkin-Elmer 2400 (II)
analyzer. Mass spectra were recorded with an API 2000 LC/MS/MS
apparatus. The thermal properties of the resulting materials were deter-
mined using a METTLER TOLEDO STARe Thermal Analysis System
apparatus. Measurements were performed at
a heating rate of
10 °C·min–1 in a nitrogen flow rate of 20 mL·min–1.
Synthesis of 1H-Tetrazole: 1H-tetrazole was synthesized as reported
in the literature.[17–19] Into a mixture of sodium azide (0.045 mol,
2.925 g), NH4Cl (0.135 mol, 7.221 g), triethylorthoformate (0.135 mol,
20 mL), AcOH (0.18 mol, 11 mL) were added. The mixture was re-
fluxed at 90 °C for 10 h. To the cooled solution, concentrated hydro-
chloric acid (2 mL) was added (the solution was acidified to pH 2–3
with concentrated hydrochloric acid). A precipitate of sodium chloride
Figure 4. TG of sodium 5-chlorotetrazolate dihydrate (imaginary line)
and sodium tetrazolate monohydrate (full line) at a heating rate of
10 °C·min–1.
razolate dihydrate could be a potential candidate for a gas gen-
erating compound.
4
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Sodium 5-Chlorotetrazolate Dihydrate by Chlorination of 1H-Tetrazole
(NaCl) was filtered off, and all solvents were removed using a rotary
evaporator. The remaining solid matter was dissolved in boiling EtOH
Copies of the data can be obtained free of charge on quoting
the depository numbers CCDC-1028253 (sodium tetrazolate monohy-
(8 mL). The clear solution obtained was left overnight in a refrigerator. drate) and CCDC-1028254 (sodium 5-chlorotetrazolate dihydrate)
The crystalline product was filtered and purified by recrystallization (Fax: +44-1223-336-033; E-Mail: deposit@ccdc.cam.ac.uk, http://
from acetone (yield: 2.838 g, 91.55%). M.p. 143.66 °C. CH2N4 www.ccdc.cam.ac.uk).
(70 g·mol): C 16.23 (calcd. 17.13); H 3.311 (2.855); N 80.034
Supporting Information (see footnote on the first page of this article):
(79.94)%. IR (KBr): ν˜ = (=C–H) 3158.51, ν(N–H) 3057.05, ν(C=N)
1658.26, ν(N=N) 1524.31, ν(C–N) 1401.98, ν(N–N) 1256.77, δ(C–H)
IR spectra of sodium tetrazolate monohydrate and sodium 5-chlorotet-
razolate dihydrate; 1H and 13C NMR. ESI-MS of sodium tetrazolate
and sodium 5-chlorotetrazolate.
1
1145.02, δ(N–H) 937.83 cm–1. H NMR (400 MHz, [D6]DMSO): δ =
9.39 (s, C-H), 7.20 (s, N-H). 13C NMR (400 MHz, [D6]DMSO): δ =
143.12 (s, C-1) ppm.
Acknowledgements
Synthesis of Sodium Tetrazolate Monohydrate: 1H-tetrazole (0.7 g,
0.01 mol) was dissolved in distilled water and sodium hydroxide solu-
tion (50%, aqueous solution, 0.01 mol) was added slowly. Meanwhile,
the pH of the solution was adjusted from 5 to 7. The reaction solvent
was removed using a rotary evaporator; A colorless solid matter was
dried by distillation of azeotrope with three 15 mL portions of EtOH
and recrystallized from EtOH. The colorless acicular crystalline solid
of sodium tetrazolate was obtained (yield: 0.856 g, 93%). M.p.
275.97 °C. IR (KBr): ν˜ = (–OH) 3296.12, ν(=C–H) 3114.54, δ(–OH)
1692.01, ν(N–N) 1286.42, δ(C–H) 1131.57 cm–1. 1H NMR (400 MHz,
[D6]DMSO): δ = 8.10 (s, H-1). 13C NMR (400 MHz, [D6]DMSO):
δ = 148.41 (s, C-1) ppm. ESI-MS: m/z = 69.2 [M]–; 41[M-N2]–.
The authors gratefully acknowledge the support of Beijing Institute of
Technology, guidance of Prof. Haixiang Gao.
References
[1] E. Makino, N. Iwasaki, N. Yagi, Chem. Pharm. Bull. 1990, 38,
201–207.
[2] G. X. Wang, B. P. Sun, C. H. Peng, Org. Process Res. Dev. 2011,
15, 986–988.
[3] Z. Wei, J. R. Li, N. Wang, Q. Zhang, D. X. Shi, K. N. Sun, Tetra-
hedron 2014, 70, 1395–1400.
[4] M. Dinca, A. Dailly, Y. Liu, C. M. Brown, D. A. Neumann, J. R.
Long, J. Am. Chem. Soc. 2006, 128, 16876–16883.
[5] D. P. Jiang, R. X. Yao, F. Ji, X. M. Zhang, Eur. J. Inorg. Chem.
2013, 4, 556–562.
[6] X. Wang, ; . S, Y. Z. Tang, X. F. Huang, Z. R. Qu, C. M. Che,
Inorg. Chem. 2005, 44, 5278–5285.
[7] R. P. Singh, R. D. Verma, D. T. Meshri, J. M. Shreeve, Angew.
Chem. Int. Ed. 2006, 45, 3584–3601.
[8] S. H. Wiedemann, M. M. Bio, L. M. Brown, Synlett 2012, 23,
2231–2236.
Synthesis of Sodium 5-Chlorotetrazolate Dihydrate: A sodium hy-
pochlorite solution (0.12 mol, 74.5 g) was added dropwise with vigor-
ous stirring into 1H-tetrazole (0.01 mol, 0.70 g) dissolved in an AcOH
solution (50%, aqueous solution, 0.12 mol) at 55 °C over a period of
6 h. All of the reaction solvents were removed using a rotary evapora-
tor; the solid matter was dried by distillation of azeotrope with three
20-mL portions of EtOH and extracted with acetone; after filtering the
NaCl, the filtrate was dried with MgSO4. Following the removal of
acetone by purging with warm air, sodium 5-chlorotetrazolate dihy-
drate was obtained as a colorless crystal with a 92.76% yield
(1.3496 g). M.p. 237.33 °C (decomposition). IR (KBr): ν˜ = (–OH)
3512.89 (m), δ(–OH) 1628.05, ν(C=N) 1376.12, ν(N=N) 1354.65,
ν(N–N) 1195.19, ν(C–Cl) 724.49 cm–1. 13C NMR (400 MHz,
[D6]DMSO): δ = 150.34 (s, C-1). ESI-MS: m/z = 102.8 [M]– (35Cl),
104.8[M]– (37Cl);75[M–N2]–; 76.8[M–N2]–; 42[M–N2–Cl+2H]–.
[9] T. M. Klapötke, S. M. Sproll, Eur. J. Org. Chem. 2009, 25, 4284–
4289.
[10] W. L. Collibee, M. Nakajima, J. P. Anselme, J. Org. Chem. 1995,
60, 468–469.
[11] J. A. C. Alves, R. A. W. Johnstone, Synth. Commun. 1997, 27,
2645–2650.
[12] S. Rayat, R. Chhabra, O. Alawode, J. Mol. Struct. 2009, 933, 38–
45.
[13] R. Stolle, Ber. Dtsch. Chem. Ges. 1929, 62, 1118–1126.
[14] J. Heppekausen, T. M. Klapötke, S. M. Sproll, J. Org. Chem.
2009, 74, 2460–2466.
[15] G. I. Koldobskiil, D. S. Soldatenko, E. S. Gerasimova, Russ. J.
Org. Chem. 1997, 33, 1771–1783.
[16] C. H. Sun, Y. C. Li, Y. Y. Li, G. Q. Li, S. P. Pang, Chin. J. Org.
Chem. 2010, 30, 424–430.
[17] T. M. Klapötke, M. Stein, J. Stierstorfer, Z. Anorg. Allg. Chem.
2008, 634, 1711–1723.
[18] R. Bronisz, Inorg. Chim. Acta 2002, 340, 215–220.
[19] F. L. Jiang CN92–108636, 1993.
[20] G. M. Sheldrick, SHELXS-97, Program for X-ray Crystal Struc-
ture Determination, Göttingen University, Germany, 1997.
[21] G. M. Sheldrick, SHELXL-97, Program for X-ray Crystal Struc-
ture Refinement, Göttingen University, Germany, 1997.
X-ray Data Collection and Structure Determination: X-ray single-
crystal diffraction data were collected with a Rigaku RAXIS RAPID
IP diffractometer equipped with a graphite at 298(2) K using Mo-Kα
radiation (λ = 0.71073 Å). The program SAINT was used to integrate
the diffraction profiles. Semi-empirical absorption corrections were
performed using the program SADABS. All of the structures were
solved by direct methods using the SHELXS 97 program of the
SHELXTL package and refined by the full-matrix least-squares
method with SHELXL 97.[20,21] All non-hydrogen atoms were refined
with anisotropic thermal parameters. The hydrogen atoms of organic
groups were placed in calculated positions in a riding model approxi-
mation with a fixed temperature factor.
Crystallographic data (excluding structure factors) for the structures in
this paper have been deposited with the Cambridge Crystallographic
Data Centre, CCDC, 12 Union Road, Cambridge CB21EZ, UK.
Received: October 23, 2014
Published Online: ᭿
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Job/Unit: Z14486
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Date: 11-12-14 18:33:36
Pages: 6
z201400486e1.xml
X. Wang, J. Liu, D. Wang, X. Bi, W. Zhao
ARTICLE
X. Wang, J. Liu,* D. Wang, X. Bi, W. Zhao ..................... 1–6
Synthesis and Characterization of Sodium 5-Chlorotetrazolate
Dihydrate by Chlorination of 1H-Tetrazole
6
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