An improved method for the synthesis of disulfides by periodic acid and sodium hydrogen sulfite in water

Article abstract of DOI:10.2174/157017810791514733

An improved method for the synthesis of disulfide in water by using periodic acid and sodium hydrogen sulfite was developed.

Full text of DOI:10.2174/157017810791514733

Letters in Organic Chemistry, 2010, 7, 415-419
415
An Improved Method for the Synthesis of Disulfides by Periodic acid and
Sodium Hydrogen Sulfite in Water
Khalid M. Khan*,a, Muhammad Tahaa, Fazal Rahima, Muhammad Alia, Waqas Jamila, Shahnaz
Perveenb and M. Iqbal Choudharya
aH. E. J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of
Karachi, Karachi-75270, Pakistan
bPCSIR Laboratories Complex, Karachi, Shahrah-e-Dr. Salimuzzaman Siddiqui, Karachi-75280, Pakistan
Received December 16, 2009: Revised March 21, 2010: Accepted March 21, 2010
Abstract: An improved method for the synthesis of disulfide in water by using periodic acid and sodium hydrogen sulfite
was developed.
Keywords: Disulfides, periodic acid, sodium hydrogen sulfite, water, improved method.
Disulfides chemistry plays a key role in organic synthesis
[1, 2]. Investigation on toxin conjugates using disulfide
bonds revealed that the disulfide-based bioconjugation
approach can be applied in a variety of cellular drug delivery
systems [3-5]. Industrially, they are widely employed as
vulcanizing agents for elastomers and rubbers [6]. Disulfides
have shown follitropin and lutropin activities in vivo [7],
while vancomycin disulfide derivatives are used as
antibacterial agents [8].
they converted alkynes into ketones in fair yields [28]. A
wide variety of iodohydrin derivatives were synthesized by
treating C=C bond compounds with H5IO6 and NaHSO3
[29]. It was also reported that iodohydroxylation of allylic
alcohols took place in an anti-Markovnikov’s fashion in
excellent yields [30]. The reaction involved the formation of
hypoiodous acid (HOI) which can easily be generated by
reacting H5IO6 with appropriate reducing agent, such as
NaHSO3 [31]. Our research group has developed some new
methods, involving sodium bromate/sodium hydrogen sulfite
combination [32-35].
Several methods have been developed for oxidative
couplings of thiols into disulfides including nitric acid
mediated transformation of thiols [9], trichloroisocyanuric
acid [10], bismuths (III) nitrate [11], atomic sulfur/sodium
hydroxide under phase transferring conditions [12], calcium
hypochlorite and silica gel [13], ion exchange catalysis in the
presence of potassium permanganate [14], superoxide ions
[15], electrochemical techniques [16], weak base on mineral
support [17], benzyltriethylammonium tetrathiomolybdate
[18], ammonium persulfate [19], benzyltriphenylphospho-
nium peroxymonosulfate [20], potassium permanganate/
copper sulfate [21], and 2,6-dicarboxypyridinium chlorochr-
omate (DCPCC) [22], O2, catalyzed by Co (II) phthalocy-
anines [23], 1,3-dibromo-5,5-dimethylhydantoin (DBDMH)
[24], I2/pyridine [25] and cetyltrimethylammonium
dichromate [26]. We have also recently reported a facile
synthesis of disulfides by using an equimolar mixture of
periodic acid and sodium hydrogen sulfite [27] in CCl4/H2O
in biphasic condition. The newly developed methodology
eliminates the previously reported use of CCl4 in aqueous
biphasic reaction conditions [27] at room temperature.
We have recently reported a facile synthesis of disulfides
by using an equimolar mixture of periodic acid and sodium
hydrogen sulfite [28] in a biphasic condition CCl4/H2O.
Herein, we report an improved method for the same
conversion by using a mixture of periodic acid and sodium
hydrogen sulfite in water.
Typically an equimolar mixture of periodic acid and
sodium hydrogen sulfite in water was reacted with 0.66 mol
ratio of thiol at room temperature for 20 to 120 min. The
newly developed methodology avoids the use of hazardous
CCl4 which makes this process environmental friendly
(Scheme 1, Table 1).
H5IO6 /NaHSO3
RSH
RSSR
H2O
Scheme 1.
Aliphatic 16-21 and benzylic thiols 12-15 were reacted
quickly and the reactions completed within 10 to 35 minutes
whereas aromatic thiols 1-11 react slowly (Table 1). Longer
reaction times in aromatic thiol conversion may be due to the
stable nature of thiol radical.
RESULTS AND DISCUSSION
The chemistry of periodic acid and sodium hydrogen
sulfite combination was first studied by Masuda et al. where
We have investigated the utility of the concept of
halohydrin chemistry (HOX, i.e. X = Br, Cl) and
successfully develop a new method. Our newly developed
method is not only environmentally friendly but also requires
no heating therefore; it is economical (Scheme 1). The use of
*Address correspondence to this author at the H. E. J. Research Institute of
Chemistry, International Center for Chemical and Biological Sciences,
University of Karachi, Karachi-75270, Pakistan; Tel: 0092214824910; Fax:
0092214819018; E-mail: hassaan2@super.net.pk; khalid.khan@iccs.edu
1570-1786/10 $55.00+.00
© 2010 Bentham Science Publishers Ltd.

416 Letters in Organic Chemistry, 2010, Vol. 7, No. 5
Khan et al.
Table 1. Formation of Disulfides with NaIO5 and NaHSO3 in Water
R
R
Entry
Yield (%)
Time (min)
Entry
Yield (%)
Time (min)
1
90
50
12
95
20
Br
2
3
85
83
80
90
13
14
85
86
35
11
Cl
Me
Cl
Me
Cl
4
5
70
82
50
40
15
16
90
78
15
15
Cl
H2N
HO
2
O2N
O
(Me)3C
6
7
8
75
85
90
85
50
70
17
18
19
88
94
89
10
20
20
NH
Br
HO
Cl
3
3
4
Cl
Cl
9
85
90
20
90
15
Me
Cl
10
11
80
88
84
45
21
90
15
Me
O2N
Cl
-
-
-
-
NO2
water as solvent eliminates the use of dangerous organic
solvent i.e. CCl4. A variety of thiols were converted into
disulfides and reaction works efficiently.
Initially we explored the oxidation of thiolphenol with
periodic acid and sodium hydrogen sulfite under differing
solvent conditions (Table 2), including CCl4/water, ethyl

An Improved Method for the Synthesis of Disulfides by Periodic acid
Letters in Organic Chemistry, 2010, Vol. 7, No. 5 417
acetate/water, acetonitrile/water, as well as pure acetonitrile
and water. Interestingly, our highest yield, with the shortest
reaction time was obtained in pure water.
1-Chloro-4-[(4-chlorophenyl)disulfanyl]benzene (2)
º
Solid; M.p = 70-73 C, 1H NMR (300 MHz, CDCl3): ꢀ
7.60 (d, J = 8.8 Hz, 4H), 7.10 (d, J = 8.8 Hz. 4H), EI MS m/z
= 285.94; Anal. Calcd for C12H8Cl2S2; C = 50.18, H = 2.81;
Found: C = 50.20, H = 2.83.
Table 2. Comparison of Disulfide Formation in Different
Solvent Systems
1-Methyl-4-[(4-methylphenyl) disulfanyl]benzene (3)
Entry
Solvent
Yield (%)
Time (min)
º
1
Solid; M.p = 43-46 C, H NMR (300 MHz, CDCl3): ꢀ
7.38 (d, J = 8.4 Hz, 4H), 7.10 (d, J = 8.4 Hz, 4H), 2.35 (s,
2xCH3, 6H); EI MS m/z = 246.05; Anal. Calcd for C14H14S2;
C = 68.24, H = 5.73, Found: C = 68.12, H = 5.60.
1
1
1
1
1
1
Water
CH3CN
90
55
60
75
73
60
50
80
CH3CN/water
CCl4/water
100
60
4-[(4-Aminophenyl) disulfanyl] phenylamine (4)
1
Solid; M.P = 77-78 °C, H NMR (300 MHz, CDCl3): ꢀ
Ethyl acetate/water
CH3CN/water
90
7.38 (d, , J = 8.4 Hz, 4H), 7.10 (d, J = 8.4 Hz, 4H), 3.94 (br
s, 2xNH2, 4H), EI MS m/z = 248.04; Anal. Calcd for
C12H12N2S2; C = 58.0 , H = 4.87; Found: C = 58.01, H =
4.78.
100
In conclusion, periodate and sodium hydrogen sulfite in
water is excellent reagent combination for chemoselective
formation of disulfides while tolerating other functional
groups such as amino and hydroxyl- groups in the same
molecule, e.g. compounds 4, 6, 16 and 19.
1-Nitro-4-[(4-nitrophenyl)disulfanyl]benzene (5)
Solid; M.p = 178-180 °C, 1H NMR (300 MHz, CDCl3): ꢀ
7.75 (d, J = 8.6 Hz 2H), 7.20 (d, J = 8.6 Hz, 2H), EI MS m/z
= 308.33; Anal. Calcd for C12H8N2O4S2; C = 46.74, H =
2.62; Found: C = 46.56, H = 9.34.
N-(4-{[4-(Acetylamino)phenyl]disulfanyl}phenyl)acetamide
(6)
EXPERIMENTAL
EI Mass spectra were measured with various MAT 711
(70 eV) spectrometers and data was tabulated as m/z. H-
Solid; M.P = 107-109 °C, 1H NMR (300 MHz, CDCl3): ꢀ
9.41 (br s, 2xNH, 2H), 7.45 (d, J = 7.8 Hz, 4H ), 7.1 (d, , J =
7.8 Hz, 4H ), ꢀ 1.41( s, 2xCH3, 6H) EI MS m/z = 332.07;
Anal. Calcd for C16H16N2O2S2; C = 57.81, H = 4.85; Found:
C = 57.77, H = 4.80
1
NMR spectra were recorded in CDCl3 using Bruker AC300
(300 MHz) machine. Splitting patterns were as follows; s,
singlet; d, doublet; dd, double doublets; t, triplet; m,
multiplet. Chemical shifts are reported in ꢀ (ppm) and
coupling constants (J) are given in Hz. The progress of all
reactions was monitored by TLC, which was performed on
2.0 X 5.0 cm aluminum sheets pre-coated with silica gel
1-Bromo-4-[(4-bromophenyl)disulfanyl]benzene (7)
º
1
Solid M.p = 88-90 C, H NMR (300 MHz, CDCl3): ꢀ
7.50 (d, J = 7.5 Hz, 4H), 7.22 (d, J = 7.5 Hz, 2H), EI MS m/z
= 376.13; Anal. Calcd for C12H8Br2S2; C = 38.32, H = 2.14;
Found: C = 38.25, H = 2.10.
60F254 to
a
thickness of 0.25 mm (Merck). The
chromatograms were visualized under ultraviolet light (254-
366 nm) or iodine vapors. Elemental analysis was performed
on a Carlo Erba 1106 elemental analyzer.
1,2-Dichloro-4-[(3,4-dichlorophenyl)disulfanyl]benzene (8)
º
1
Solid; M.p = 84-87 C, H NMR (300 MHz, CDCl3): ꢀ
8.4 (d, 2H, J = 2.3 Hz), 8.11 (dd, J = 8.9, 2.2 Hz, 2H), 7.84
(d, J = 8.9 Hz. 2H), EI MS m/z = 356.12; Anal. Calcd for
Cl2H6Cl4S2; C = 40.47, H = 1.70; Found: C = 40.44, H =
1.67.
General Procedure for the Reaction
Typical Procedure for the Preparation of Disulfides 1-21
To solution of premixed mixture of H3IO5 (9 mmol) and
NaHSO3 (9 mmol) in H2O (25 mL) and (6 mmol) thiol was
added slowly during a period of 10 min, and the mixture was
stirred at room temperature for appropriate time as shown in
Table 1. The reaction was monitored by TLC and after
completion extracted with ethyl acetate (20 mL x 3). The
combined organic layer was washed with aqueous Na2S2O3
and dried over Na2SO4. The solvent was evaporated in vacuo
to obtain crude product which was purified by column
chromatography eluted with pure n-hexane.
1,3-Dichloro-2-[(2,6-dichlorophenyl)disulfanyl]benzene(9)
º
1
Solid; M.p = 82-85 C, H NMR (300 MHz, CDCl3): ꢀ
7.71 (d, J = 6.9 Hz, 4H), 7.20 (t, J = 6.9 Hz, 2H), EI MS m/z
= 356.87; Anal. Calcd for Cl2H6Cl4S2; C = 40.47, H = 1.70;
Found: C = 40.45, H =1.67.
2-Chloro-4-[(3-chloro-4-nitrophenyl)disulfanyl]-1-nitro-
benzene (10)
º
Solid; M.p = 146-149 C, 1H NMR (300 MHz, CDCl3): ꢀ
1-(Phenyldisulfanyl) benzene (1)
8.71 (d, 2H, J= 2.4Hz), 8.30 (dd, J = 8.6 , 2.1 Hz, 2H), 8.05
(d, J = 8.6 Hz, 2H), EI MS m/z = 375.91; Anal. Calcd for
Cl2H6Cl2N2O4S2; C = 38.21, H = 1.60; Found: C = 38.11, H
=1.56.
º
Solid; M.p = 58-61 C, 1H-NMR (300 MHz, CDCl3): ꢀ
7.30 (dd, J = 7.3, 2.2 Hz, 4H), 7.40 (dd, J = 7.4, 2.1 Hz, 2H)
7.55 (dd, J = 7.9, 1.3 Hz, 4H); EI MS m/z = 218 Anal. Calcd
for C12H10S2; C = 66.01, H = 4.62; found: C = 66.02, H =
4.625.
1-Nitro-3-[(3-nitrophenyl)disulfanyl]benzene (11)
º
Solid; M.p = 78-81 C, 1H NMR (300 MHz, CDCl3): ꢀ
7.89 (m , 2H), 7.68 (dd, J = 1.2, 2.1 Hz, 2H), 7.30 (m, 2H),

418 Letters in Organic Chemistry, 2010, Vol. 7, No. 5
Khan et al.
6.95 (dd, J = 7.2, 6.1 Hz, 2H), EI MS m/z = 308.33; Anal.
Calcd for C12H8N2O4S2; C = 46.74, H = 2.62; Found: C =
46.70, H = 2.60.
1-(Pentyldisulfanyl)pentane (21)
1
Liquid; H NMR (300 MHz, CDCl3): ꢀ 3.12 (t, J = 6.8
Hz, 2xCH2, 4H), 2.4-2.32 (m, 6xCH2, 12H), 1.32 (t, J = 6.9
Hz 2xCH3, 6H); EI MS m/z = 206.41 ; Anal Calcd for C10 H22
S2; C = 51.16, H = 9.81; Found: C = 51.10, H = 9.78.
1-Bromo-4-{[(4-bromobenzyl)disulfanyl]methyl}benzene
(12)
º
Solid; M.p = 83-84 C, 1H NMR (300 MHz, CDCl3): ꢀ
7.60 (d, J = 7.9 Hz ,4H), 7.40 (d, J = 7.9 Hz, 4H), 2.68 (s,
2xCH2, 4H), EI MS m/z = 401.87, Anal. Calcd for
C14H12Br2S2; C = 41.60, H = 2.99; Found: C = 41.56, H =
2.90.
ACKNOWLEDGEMENTS
Authors gratefully acknowledge the financial support for
Pakistan Telecommunication Company Limited (PTCL)
through
a
research project entitled, “Synthesis of
Bis(4-methylbenzyl) disulfide (13)
Leishmanicidal Chemotherapeutic Agents.”
1
°
Solid; M.p = 47-49 C, H NMR (300 MHz, CDCl3): ꢀ
7.38 (d, J = 8.4 Hz, 4H), 7.10 (d, J = 8.4 Hz, 4H), 2.78 (s,
2xCH2, 4H), 2.35 (s, 2xCH3, 6H); EI MS m/z = 274.08; Anal.
Calcd for C16H18S2; C = 70.0, H = 6.60; Found: C = 70.02, H
= 6.61.
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º
1
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[12]
1
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An Improved Method for the Synthesis of Disulfides by Periodic acid
Letters in Organic Chemistry, 2010, Vol. 7, No. 5 419
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