Selective and efficient oxidation of diaryl carbazide to diaryl carbazone with NaNO2-acetic anhydride under mild conditions

Article abstract of DOI:10.1081/SCC-120014033

In this paper, ten diaryl carbazide undergo selective and rapid oxidation to the corresponding diaryl carbazone using NaNO₂-acetic anhydride as a novel oxidant under mild conditions for the first time.

Full text of DOI:10.1081/SCC-120014033

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SELECTIVE AND EFFICIENT OXIDATION OF DIARYL
CARBAZIDE TO DIARYL CARBAZONE WITH NaNO2–ACETIC
ANHYDRIDE UNDER MILD CONDITIONS
Xiao-Chuan Li a , Yu-Lu Wang b & Jin-Ye Wang c
a College of Chemical and Environmental Science , Henan Normal University , Xinxiang,
Henan, 453002, P.R. China
b The Key Laboratory of Environmental Science and Technology of High Education of Heana
Province , P.R. China
c Shanghai Institute of Organic Chemistry , Chinese Academy of Science , Shanghai, 200032,
P.R. China
Published online: 16 Aug 2006.
To cite this article: Xiao-Chuan Li , Yu-Lu Wang & Jin-Ye Wang (2002) SELECTIVE AND EFFICIENT OXIDATION OF DIARYL
CARBAZIDE TO DIARYL CARBAZONE WITH NaNO2–ACETIC ANHYDRIDE UNDER MILD CONDITIONS, Synthetic Communications:
An International Journal for Rapid Communication of Synthetic Organic Chemistry, 32:21, 3285-3288, DOI: 10.1081/
SCC-120014033
To link to this article: http://dx.doi.org/10.1081/SCC-120014033
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SYNTHETIC COMMUNICATIONS
Vol. 32, No. 21, pp. 3285–3288, 2002
SELECTIVE AND EFFICIENT OXIDATION
OF DIARYL CARBAZIDE TO DIARYL
CARBAZONE WITH NaNO2–ACETIC
ANHYDRIDE UNDER MILD CONDITIONS
Xiao-Chuan Li,1 Yu-Lu Wang,2, and Jin-Ye Wang3
*
1College of Chemical and Environmental Science,
Henan Normal University, Xinxiang,
Henan, 453002, P.R. China
2The Key Laboratory of Environmental Science
and Technology of High Education of
Heana Province, P.R. China
3Shanghai Institute of Organic Chemistry,
Chinese Academy of Science,
Shanghai, 200032, P.R. China
ABSTRACT
In this paper, ten diaryl carbazide undergo selective and rapid
oxidation to the corresponding diaryl carbazone using
NaNO2–acetic anhydride as a novel oxidant under mild
conditions for the first time.
*Corresponding author. E-mail: xiaochuanli@263.net
3285
DOI: 10.1081/SCC-120014033
Copyright & 2002 by Marcel Dekker, Inc.
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3286
LI, WANG, AND WANG
Azo compounds have been widely used as dyes and analytical
regents,[1] photoregulation of polypeptide fucniton[2] and materials for
non-linear optics and for storage information in laser disks.[3] Many azo
compounds are in great need because of the above functions.
The oxidation of diaryl carbazide into diaryl carbazone is an important
transformation in organic synthesis. We have been paying particular and
continuous attention to this field. In the previous work, our laboratory has
used NBS/pyridine,[4] FeCl3/H2SO4[5] in liquid phase, K3Fe(CN)6/KOH[6] in
solid state as effective oxidants and led to relatively better results. But these
methods suffer from the drawbacks of tedious operation;[4] the using of a large
amount of solvent;[4] accurately control of molar ratio of oxidants;[5] strong
acid or basic media.[5,6] These limit their application in organic synthesis.
NaNO2–Ac2O is known method for the oxidation of a variety of
alcohols into their corresponding carbonyl compounds.[7] After our experi-
ments, it was demonstrated that this is an effective reagent for the oxidation of
diaryl carbazide under mild conditions. All reactions were performed
smoothly at room temperature and completed within 50min. For the
first time this oxidation system was used to synthesize diaryl carbazone
(Sch. 1). Furthermore, this method only requires simple instrument, cheap
oxidant and easy work-up procedure. Ten diarly carbazone compounds were
synthesized in excellent yields (Table 1). In addition, diaryl carbodiazone is
not produced under this reaction condition even if the excess oxidant is used.
An oxidation study of 1,5-diphenylcarbazide with different ratio of
Ac2O : NaNO2 is shown in Table 2. If NaNO2 was used for the oxidation
alone, the reaction did not occur after stirring 24 h. The optimum molar
ratio of Ac2O : NaNO2 (2 : 6) is required for the complete oxidation. And no
additional products were identified from this reaction.
Overall, we recommend this simple, efficient and economical
procedure for the oxidation of diaryl carbazide with excellent yields under
mild conditions. In all cases, clean transformation could be detected by
TLC. We believe that the present methodology is an important addition
to existing methodology.
Scheme 1.

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OXIDATION OF DIARYL CARBAZIDE TO DIARYL CARBAZONE
3287
Table 1. The
NaNO2–Ac2O
Oxidation
of
Diaryl
Carbazide
with
Yield
(%)
M.P.
(ꢀC)
Lit. M.P.
(ꢀC)[4–6]
Product
X
Color
2a
2b
2c
2d
2e
2f
2g
2h
2i
H
2-Me
3-Me
4-Me
2,3-Me2
2,5-Me2
2,6-Me2
3,4-Me2
4-EtO
Orange
Yellow
Brown
Orange
Orange
Yellow
Yellow
Orange
Orange
Brown
94
93
155–157
125–127
166–168
132–133 133–134
116–118
158–160–
194–195
93–95
158–161
242–244
155–156.5
127–128
90165–167
89
90115–117
91
93
89
95
88
195–196
–
160–161
243–245
2j
4-NO2
Table 2. Oxidation of 1,5-Diphenylcarbazide with
Different Ratio of NaNO2 : Ac2O
Substrate : Ac2O :
NaNO2
Reaction
Time
Yield
(%)
Entry
1
2
3
4
5
6
7
8
1 : 0: 6
1 : 1 : 1
1 : 1 : 2
1 : 1 : 4
1 : 1 : 6
1 : 2 : 2
1 : 2 : 4
1 : 2 : 6
1 : 2 : 8
24 h
2 h
2 h
2 h
a little
58
67
73
78
79
89
94
94
2 h
50min
50min
50min
50min
3 h
9
101 : 2 : 6
93
EXPERIMENTAL
Melting points were determined on kolfler micro melting point
apparatus without correction. Elemental analyses were performed on a
Perkin-Elmer 240C analytical instrument. Infrared spectra were recorded
on a SP3-300 spectra photometer using KBr pellets. 1H NMR spectra
were measured in CDCl3 using TMS as internal standard with a
JEOL-Fx-90Q NMR spectrometer. Mass spectra were recorded on
VG-ZAB-HS spectrometer.

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3288
LI, WANG, AND WANG
General Procedure for the Preparation of Diaryl Carbazones
A mixture of diaryl carbazide (1 mmol), acetic anhydride (0.204 g,
2 mmol), NaNO2 (0.414 g, 6 mmol) in dichloromethane (20 mL) was vigor-
ously stirred with magnetic stirrer at room temperature. After completion of
the reaction (TLC), the reaction mixture was filtered. Dichloromethane was
removed by simple distillation. The resulting solid was recrystallized from
EtOH–H2O (3 : 1) mixture and dried under vacuum.
1
All the products were identified by IR, H NMR, MS, and elemental
analysis. The spectral and analytical data of compounds 2f and 2h, not
known in the literature, are listed below:
Compound 2f: IR (KBr) ꢀ: 3475, 3321, 3043, 2913, 2874, 1690, 1605,
1
1574, 1478, 1411 (cmꢁ1); H NMR (CDCl3) ꢁ (ppm): 2.30(s, 6H, 2CH ),
3
2.36 (s, 6H, 2CH3), 6.64–7.17 (m, 6H, ArH), 7.35–7.86 (d, 2H, NHNH); MS
(70eV) m/z: 296 (Mþ) Anal. calcd. for C17H20N4O: C, 68.90; H, 6.80;
N, 18.90. Found: C, 68.73; H, 6.53; N, 18.57.
Compound 2h: IR (KBr) ꢀ: 3411, 3318, 3045, 2916, 2862, 1691, 1592,
1
1493, 1474, 1450(cm ꢁ1); H NMR (CDCl3) ꢁ (ppm): 2.32 (s, 6H, 2CH3),
2.38 (s, 6H, 2CH3), 6.51–7.23 (m, 6H, ArH), 7.40–7.85 (d, 2H, NHNH); MS
(70eV) m/z: 296 (Mþ) Anal. calcd. for C17H20N4O: C, 68.90; H, 6.80;
N, 18.90. Found: C, 68.32; H, 6.67; N, 18.39.
REFERENCES
1. Russ, H.W.; Tappe, H. Eur. Pat. Appl. EP. 1994, 629, 627.
2. Sefkow, M.; Kaatz, H. Tetrahedron Letters 1999, 40(36), 6561.
3. Nakazumi, H. J. Soc. Dyers and Colourists 1998, 104, 121.
4. Wang, Y.L.; Duan, Z.F.; Shi, L.; Wang, X.Y.; Li, J.P. Synth. Commun.
1999, 29, 423.
5. Wang, Y.-L.; Shi, L.; Jia, X.-S.; Pan, F.; Ma, D.-L.; Wang, X.-Y. Synth.
Commun. 1999, 29, 53.
6. Xiao, J.-P.; Wang, Y.-L.; Zhou, Q.-X. Synth. Commun. 2001, 31, 661.
7. Babasaheb P. Bandagr; Vaibhav S. Sadavarte; Lavkumar S. Uppalla.
J. Chem. Soc. Perkin Trans. 1 2000, 21, 3559.
Received in the Netherlands October 20, 2001