Lithium/Sodium Perchlorate Catalyzed Synthesis of Symmetrical Diaryl Sulfoxides

Article abstract of DOI:10.1081/SCC-120027723

Synthesis of diaryl sulfoxides from aromatics and thionyl chloride catalyzed by LiClO₄/NaClO₄ at room temperature is described. Mild reaction conditions, simple work-up, inexpensive and easily available catalysts are important and attractive features of this method.

Full text of DOI:10.1081/SCC-120027723

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Lithium/Sodium Perchlorate Catalyzed Synthesis of
Symmetrical Diaryl Sulfoxides
a
a
B. P. Bandgar & S. S. Makone
a
Organic Chemistry Research Laboratory, School of Chemical Sciences , Swami
Ramanand Teerth Marathwada University , Nanded, 431 606, India
Published online: 16 Aug 2006.
To cite this article: B. P. Bandgar & S. S. Makone (2004) Lithium/Sodium Perchlorate Catalyzed Synthesis of Symmetrical
Diaryl Sulfoxides, Synthetic Communications: An International Journal for Rapid Communication of Synthetic Organic
Chemistry, 34:4, 743-750, DOI: 10.1081/SCC-120027723
To link to this article: http://dx.doi.org/10.1081/SCC-120027723
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w
SYNTHETIC COMMUNICATIONS
Vol. 34, No. 4, pp. 743–750, 2004
Lithium/Sodium Perchlorate Catalyzed
Synthesis of Symmetrical Diaryl Sulfoxides
*
B. P. Bandgar and S. S. Makone
Organic Chemistry Research Laboratory, School of Chemical Sciences,
Swami Ramanand Teerth Marathwada University, Nanded, India
ABSTRACT
Synthesis of diaryl sulfoxides from aromatics and thionyl chloride
catalyzed by LiClO /NaClO at room temperature is described. Mild
4
4
reaction conditions, simple work-up, inexpensive and easily available
catalysts are important and attractive features of this method.
Key Words: Aryl sulfoxides; Arenes; Thionyl chloride; Lithium
perchlorate; Sodium perchlorate.
Sulfoxides and sulfones are interesting functional groups possessing
manyfold reactivity for conversion of a variety of organic sulfur compounds in
[1]
the field of drugs and pharmaceuticals. Especially, sulfoxides deserved
*
Correspondence: B. P. Bandgar, Organic Chemistry Research Laboratory, School of
Chemical Sciences, Swami Ramanand Teerth Marathwada University, Nanded
4
31 606, India; Fax: 0091-2462-229245; E-mail: bandgar_bp@yahoo.com.
43
7
DOI: 10.1081/SCC-120027723
0039-7911 (Print); 1532-2432 (Online)
www.dekker.com
Copyright # 2004 by Marcel Dekker, Inc.

ORDER
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7
44
Bandgar and Makone
[2]
much attention as important chiral auxiliary in asymmetric synthesis and
[3]
particularly in carbon-carbon bond forming processes. In addition, aryl
sulfonium salts have also been used extensively as photoactive cationic
[
initiators and for the photogeneration of protonic acid in the lithographic
4]
[
5]
resist field. In view of the importance of sulfoxides as chiral synthons in
organic synthesis, a simple and high yielding one-pot approach for their
synthesis is highly desirable. Sulfoxides are usually prepared by indirect
methods, which involve the oxidation of sulfides, the reduction of sulfones and
the reaction of organometallic reagents with sulfinic acid esters, mixed
[
6]
anhydrides or sulfines.
The direct methods for the preparation of diaryl sulfoxides involve the
[7]
Friedel-Crafts sulfinylation of arenes using Lewis acids as well as Bronsted
[8]
acids. Other methods including the addition of aryl Grignard reagents to
thionyl chloride, the reaction of SO with arenes in the presence of Magic
2
[
acid and scandium triflate
9]
[10]
catalyzed reaction of SOCl with arenes also
2
produce aryl sulfoxides. However, many of these methods have limited
synthetic scope due to the use of corrosive, hazardous, oxidizing, expensive
and difficult to handle reagents, lack of selectivity and the formation of a
mixture of products containing sulfonium salts and chlorinated byproducts
along with desired sulfoxides. Thus there is a need to develop a simple,
convenient, rapid and high yielding method for the preparation of sulfoxides
under mild reaction conditions.
The development of method which allows the reaction under essentially
mild and neutral conditions should heighten the synthetic potential of the
reaction. In recent years lithium perchlorate has gained a lot of importance as
[11–14]
versatile reagent for effecting organic transformations.
Lithium
perchlorate offers a convenient procedure to carry out the reactions under
essentially neutral reaction and work-up conditions. These special properties
inherent to lithium perchlorate prompted us to disclose a mild and efficient
procedure for synthesis of diaryl sulfoxides (Sch. 1).
The treatment of anisole with thionyl chloride in the presence of 10%
lithium perchlorate at ambient temperature afforded dianisyl sulfoxide in 80%
yield. In a similar fashion, several arenes reacted smoothly with thionyl
chloride to give the corresponding diary sulfoxides in high yields. In all cases,
the reactions proceeded efficiently at ambient temperature with high
Scheme 1.

ORDER
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Synthesis of Diaryl Sulfoxides
745
regioselectivity. The activated arenes gave the products in excellent yields in a
short reaction time (Table 1). However unactivated arenes such as naphtha-
lene, chlorobenzene, bromobenzene, iodobenzene, toluene, xylene and
mesitylene also reacted well with thionyl chloride in the presence of 10%
LiClO to afford the corresponding aryl sufloxides in high yields. Sodium
4
Table 1. LiClO
4
/NaClO
4
catalyzed synthesis of diaryl sulfoxides.
Time Yield
a,b
Entry
a
Arene
Product
Catalyst
(h)
(%)
LiClO
NaClO4
4
3.0
2.5
80
81
LiClO
NaClO4
4
3.0
3.0
85
87
b
c
LiClO4
NaClO
3.0
3.5
88
84
4
LiClO4
NaClO
2.5
2.5
89
82
d
4
LiClO
NaClO4
4
3.0
3.5
79
84
e
f
LiClO
NaClO
4
1.5
2.0
82
86
4
LiClO
NaClO
4
2.0
2.5
83
82
g
4
LiClO4
NaClO
2.0
2.0
88
86
h
4
(continued)

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7
46
Bandgar and Makone
Table 1. Continued.
a,b
Time Yield
(%)
Entry
i
Arene
Product
Catalyst
LiClO4
(h)
4.0
4.5
80
75
NaClO
4
LiClO4
NaClO
3.5
4.0
70
78
j
4
LiClO
NaClO
4
3.0
3.0
82
84
k
4
4
LiClO
NaClO
4
3.5
3.5
89
87
l
LiClO4
NaClO
2.0
2.5
75
79
m
4
LiClO4
NaClO
4.5
4.5
76
75
n
o
4
LiClO4
NaClO
3.5
3.0
82
77
4
p
q
1-Nitronaphthalene
Nitrobenzene
No reaction
No reaction
No reaction
No reaction
LiClO
NaClO4
4
24
24
24
24
24
24
24
24
–
–
–
–
–
–
–
–
LiClO
NaClO
LiClO4
NaClO
4
4
4
-Nitroanisole
4
s
4-Nitrotoluene
LiClO
4
NaClO4
a
Isolated and unoptimized yields.
1
b
Products were characterized by H NMR, IR spectroscopy, elemental analysis and by
comparison with authentic samples.

ORDER
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Synthesis of Diaryl Sulfoxides
747
perchlorate also worked well as a catalyst (10%) for the synthesis of diaryl
sulfoxides. Similar yields and selectivity were obtained with NaClO under
4
the present reaction conditions.
The scope and limitations of the catalysts, LiClO and NaClO were
4
4
examined by considering activated and unactivated arenes and the results are
summarized in the Table 1. The deactivated arenes having electron with-
drawing substituents such as nitro group did not undergo sulfinylation even
after stirring the reaction mixture for longer time and using increasing mol %
of catalyst (20%, 30% and 40%) under the present reaction conditions. It is
important to note that heterocyclic arenes such as thiophene also underwent
smooth sulfinylation which is otherwise problematic with highly acidic
catalysts. The present method is simple, convenient and regioselective,
affording high yields of products. In addition, this method does not require
anhydrous conditions and no precautions need to be taken to exclude moisture
from the reaction media. Lithium perchlorate and sodium perchlorate are
found to be the best catalysts for the synthesis of aryl sulfoxides from activated
arenes and surprisingly, these are only inexpensive and easily available
catalysts effective for sulfinylation of unactivated aromatics, of course
requiring longer reaction time. Cleaner reactions, high yields of products,
greater selectivity and simple work-up are important features of this method.
In conclusion, LiClO and NaClO are inexpensive and easily available
4
4
catalysts useful for the synthesis of diaryl sulfoxides from arenes and thionyl
chloride under mild reaction conditions. In addition to its efficiency and
simplicity, this method furnished excellent yields of the products with high
regioselectivity.
EXPERIMENTAL
General Procedure
A mixture of aromatic compound (10 mmol), thionyl chloride (5 mmol)
and lithium perchlorate (10 mol%) in THF (10 ml) was stirred at room
temperature for 3 h. After completion of the reaction (TLC), the solvent was
removed under reduced pressure. The product was extracted with dichloro-
methane (2 Â 15 mL) and organic layer was washed with water (10 mL) and
then dried with anhydrous sodium sulfate. Removal of the solvent under
reduced pressure furnished crude product which was further purified by
column chromatography (pet. ether : ethyl acetate ¼ 8.2).
Di-(4-methoxyphenyl) sulfoxide (2a). m.p. ¼ 958C; IR (neat): 780,
2
1
1
; H NMR
8
40, 1040, 1210, 1250, 1360, 1480, 1585, 2850, 2920 cm
(
300 MHz, CDCl ): G3.95 (s, 6H, 2 Â OMe), 7.1 (d, 4H, J ¼ 8.0 Hz, Ar-H),
3

ORDER
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7
48
Bandgar and Makone
7
.4 (d, 4H, J ¼ 8.0 Hz, Ar-H). Anal. calcd. for C H SO (262.33): C,
1
4
14
3
6
4.10%; H, 5.37%; S, 12.22%. Found: C, 63.99%; H, 5.29%; S, 12.31%.
Di-(3,4-dimethoxyphenyl) sulfoxide (2b). Oil; IR (KBr): 780, 840,
2
035, 1215, 1250, 1355, 1475, 1585, 2855, 2925 cm ; H NMR (300 MHz,
1 1
1
CDCl ): G3.98 (s, 12H, 4 Â OMe), 6.95 (d, 2H, J ¼ 8.0 Hz, Ar-H), 7.40
3
(
calcd. for C H O S (322.38): C, 69.61%; H, 5.63%; S, 9.95%. Found: C,
d, 2H, J ¼ 2.3 Hz, Ar-H), 7.60 (dd, 2H, J ¼ 2.3 and 8.0 Hz, Ar-H) Anal.
16 18 5
6
9.71%; H, 5.70%; S, 9.89%.
Di-(2,4-dimethoxyphenyl sulfoxide (2c). m.p. ¼ 1278C; IR (KBr):
21 1
035, 1380, 1430, 1590, 2985, 3050 cm . H NMR (300 MHz, CDCl ):
1
3
G3.85 (s, 12H, 4 Â OMe), 6.9 (d, 2H, J ¼ 1.7 Hz, Ar-H), 7.2 (dd, 2H,
J ¼ 1.7 and 8.4 Hz, Ar-H), 7.45 (d, 2H, J ¼ 8.4 Hz, Ar-H). Anal. calcd. for
C H O S (322.38); C, 69.61%; 45.63%; S, 9.95. Found: C, 69.54; H, 5.58;
1
6 18 5
S, 10.05.
Di-(2,5-dimethoxylphenyl) sulfoxide (2d). m.p. ¼ 115–1178C; IR
21 1
KBr): 775, 845, 1030, 1210, 1250, 1360, 1470, 1585, 2855, 2920 cm ; H
(
NMR (300 MHz, CDCl ): G3.90 (s, 12H, 4 Â OMe), 6.90 (d, 2H, J ¼ 8.5 Hz,
3
Ar-H), 7.30 (dd, 2H, J ¼ 1.7 and 8.5 Hz, Ar-H), 7.40 (d, 2H, J ¼ 1.7 Hz, Ar-
H) Anal. calcd. for C H O , S (322.38): C, 69.61%; H, 5.63%; S, 9.95%.
1
6 18 5
Found: C, 69.57%; H, 5.69%; S, 10.05%.
Di-(3,4-methylenedioxyphenyl) sulfoxide (2e). m.p. ¼ 144–1458C; IR
21 1
neat): 1030, 1440, 1590, 2990, 3020 cm . H NMR (300 MHz, CDCl ): G5.8
(
3
(
calcd. for C H SO (226.3): C, 74.36; H, 4.45; S, 14.17. Found: C, 74.18; H,
s, 4H, 2 Â OCH ), 6.9 (d, 2H, J ¼ 8.1 Hz, Ar-H), 7.1 (m, 4H, Ar-H). Anal.
2
1
4 10
4
.54; S, 14.21.
Di-(4-methylphenyl) sulfoxide (2f). m.p. ¼ 958C; IR (neat): 600, 770,
2
030, 1320, 1450, 1587, 2855, 2925 cm ; H NMR (300 MHz, CDCl ):
1
1
1
3
G2.35 (s, 6H, 2 Â Me), 7.2 (d, 4 H, J ¼ 8.0 Hz, Ar-H), 7.35 (d, 4H, J ¼ 8.0 Hz,
Ar-H). Anal. calcd. for C H SO (230.33): C, 73.01%; H, 6.13%; S, 13.92%.
1
4 14
Found: C, 72.97%; H, 6.22%; S, 14.01%.
Di-(3,4-dimethylphenyl) sulfoxide (2g). b.p. ¼ 134–1358C/760 mm of
21 1
Hg; IR (neat): 600, 775, 1024, 1325, 1452, 1585, 2850, 2920 cm ; H NMR
(
300 MHz, CDCl ): G2.40 (s, 12H, 4 Â Me), 7.25 (d, 2H, J ¼ 1.2 Hz, Ar-H),
3
7
.30 (d, 2H, J ¼ 8.0 Hz, Ar-H), 7.75 (dd, 2H, J ¼ 1.2 8.0 Hz, Ar-H) Anal.
calcd. for C H SO (258.39): C, 74.37%; H, 7.02%; S, 12.41%. Found: C,
16 18
7
4.49%; H, 6.95%; S, 12.36%.
Di-(2,5-dimethylphenyl) sulfoxide (2h). m.p. ¼ 167–1698C; IR (KBr):
2
1
1
; H NMR
605, 770, 1045, 1210, 1325, 1445, 1585, 2850, 2915 cm
(
300 MHz, CDCl ): G2.40 (s, 12H, 4 Â Me), 7.1 (d, 2H, J ¼ 8.2 Hz, Ar-H),
3
7
.4 (dd, 2H, J ¼ 1.2 and 8.2 Hz, Ar-H), 7.65 (d, 2H, J ¼ 1.2 Hz, Ar-H) Anal.
calcd. for C H SO (258.39): C, 74.37%; H, 7.02%; S, 12.41%. Found: C,
16 18
74.43%; H, 7.12%; S, 12.47%.

ORDER
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Synthesis of Diaryl Sulfoxides
749
Di-(2,4,6-trimethylphenyl) sulfoxide (2i). m.p. ¼ 162–1638C; IR
21 1
KBr): 1030, 1440, 1590, 2985, 3040 cm ; H NMR (300 MHz, CDCl ):
3
(
G2.23 (s, 12H, 4 Â Me), 6.79 (s, 4H, Ar-H) Anal. calcd. for C H SO
1
8 22
(
286.44): C, 75.48%; H, 7.74%; S, 11.19%. Found: C, 75.61%, H, 7.81%; S,
1
1.08%.
Di-(4-fluorophenyl) sulfoxide (2j). Oil; IR (neat): 780, 1040, 1330,
2
450, 1580, 2840, 2910 cm ; H NMR (300 MHz, CDCl ): G7.15 (d, 4H,
1 1
1
3
J ¼ 8.3 Hz, Ar-H), 7.40 (d, 4H, J ¼ 8.3 Hz, Ar-H), Anal. calcd. for
C H SOF , (238.26): C, 60.49%; H, 3.39%; S, 13.46%; F, 15.95. Found:
2
1
2
8
C, 60.55%; H, 3.45%; S, 13.39%, F, 16.02%.
Di-(4-chlorophenyl) sulfoxide (2k). m.p. ¼ 1438C; IR (neat): 705,
2
1
1
; H NMR (300 MHz,
1030, 1110, 1340, 1455, 1587, 2850, 2930 cm
CDCl ): G6.97 (d, 4H, J ¼ 8.15 Hz, Ar-H), 7.3 (d, 4H, J ¼ 8.15 Hz, Ar-H),
3
Anal. calcd. for C H SOCl , (271.16): C, 53.15%; H, 2.97%; S, 11.83%; Cl,
1
2
8
2
2
6.15. Found: C, 53.25%; H, 3.05%; S, 11.99%, Cl, 26.02%.
Di-(4-bromophenyl) sulfoxide (2l). m.p. ¼ 1538C; IR (neat): 600, 710,
2
1
1
; H NMR (300 MHz,
1055, 1120, 1340, 1450, 1580, 2840, 2910 cm
CDCl ): G7.1 (d, 4H, J ¼ 8.4 Hz, Ar-H), 7.4 (d, 4H, J ¼ 8.4 Hz, Ar-H), Anal.
3
calcd. for C H SOBr , (360.07): C, 40.03%; H, 2.24%; S, 8.91%; Br, 44.38.
1
2
8
2
Found: C, 4.11%; H, 2.32%; S, 8.82%, Br, 44.46%.
Di-(4-iodophenyl) sulfoxide (2m). m.p. ¼ 138–1408C; IR (neat): 500,
21 1
30, 1030, 1130, 1340, 1460, 1590, 2840, 2925 cm ; H NMR (300 MHz,
7
CDCl ): G7.05 (d, 4H, J ¼ 8.0 Hz, Ar-H), 7.42 (d, 4H, J ¼ 8.0 Hz, Ar-H),
3
Anal. calcd. for C H SOI , (454.07): C, 31.74%; H, 1.78%; S, 7.06%; I,
1
2
8
2
5
5.89. Found: C, 31.82%; H, 1.85%; S, 7.12%, I, 55.78%.
Di-(2-naphthyl) sulfoxide (2n). m.p. ¼ 162–1648C; IR (KBr): 1050,
21 1
120, 1590, 3010 cm ; H NMR (300 MHz, CDCl ): G6.90 (m, 8H, Ar-H),
1
3
7.2 (m, 1H, Ar-H), 7.4 (m, 4H, Ar-H) Anal. calcd. for C H SO, (302.39):
C, 79.44%; H, 4.67%; S, 10%. Found: C, 79.35;H, 4.72; S, 1053%.
2
0 14
Di-(2-thiophene) sulfoxide (2o). b.p. ¼ 128–1308C/760 mm of Hg; IR
21 1
neat): 1030, 1510, 1600, 3010 cm ; H NMR (300 MHz, CDCl ): G7.2–7.5
(
(
3
m, 6H, Ar-H), Anal. calcd. for C H S O, (214.34): C, 44.83%; H, 2.82%;
8
6 3
S, 44.88%. Found: C, 44.77%; H, 2.91%; S, 44.79%.
REFERENCES
1
. (a) Lubineau, A.; Auge, J. Top Curr. Chem. 1999, 206, 1; (b) Sinou, D.
Top Current Chem. 1999, 206, 41; (c) Li, C.J.; Chan, T.H. Tetrahedron
Lett. 1999, 51 (1), 149; (d) Fringuelli, F.; Piermatti, O.; Pizro, F.
Heterocycles 1999, 50, 611; (e) Lubineau, A.; Auge, J. Queneau Synthesis
1994, 741; (f) Li, C.J. Chem. Rev. 1993, 93, 2023.

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7
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Bandgar and Makone
2
3
4
. (a) Holland, H.L. Chem. Rev. 1988, 88, 473; (b) Block, E. Angew. Chem.
Int. Ed. Engl. 1992, 31, 1135.
. (a) Solladie, G. Synthesis 1981, 185; (b) Carreno, M.C. Chem. Rev. 1995,
95, 1717; (c) Davis, S.G.; Loveridge, T.; Clough, J.M. Synlett 1997, 66.
. (a) Magnus, P.D. Tetrahedron 1977, 33, 2019; (b) Madesclaire, M.
Tetrahedron 1988, 44, 6337.
5. Crivello, J.V.; Lam, J.H.W. Macromolecules 1977, 10, 1307.
6. Miller, R.D.; Renaldo, A.F.; Ito, J. J. Org. Chem. 1988, 53, 5571.
7. Drabowicz, J.; Kielbasinski, P.; Mikolajczyk, M. The Chemistry of
Sulfones and Sulfoxides; Patai, S., Rappoport, Z., Stirling, C.J.M., Eds.;
Wiley: New York, 1988; Chap. 8.
8
. (a) Olah, G.A.; Nishimura, J. J. Org. Chem. 1974, 39, 1203; (b)
Chaser, O.W.; Pratt, T.M. Phosphorus Sulfur Relat. Elem. 1978, 5, 35.
. (a) Yamamoto, K.; Miyatake, K.; Nishimura, Y.; Tsuchida, E. J. Chem.
Soc. Chem. Commun. 1996, 2099; (b) Olah, G.A.; Marinez, E.R.; Surya
Prakash, G.A. Synlett 1999, 1397.
9
1
1
1
1
1
0. Yadav, J.S.; Subba Reddy, B.V.; Shrinivasa Rao, R.; Praveen Kumar, S.;
Nagaiah, K. Synlett 2002, 5, 784.
1. Babu, B.S.; Balsubramanian, K.K. Tetrahedron Lett. 1998, 39, 9287 and
references cited therein.
2. Sankaraman, S.; Nesakumar, J.E. Eur. J. Org. Chem. 2000, 2003 and
references cited therein.
3. (a) Grieco, P.A. Aldrichima Acta 1991, 24, 59; (b) Balsubramanian, K.K.
Across Organics Acta 1999, 6, 12.
4. (a) Yadav, J.S.; Subba Reddy, B.V.; Murthy, C.V.S.R.; Maheshkumar, G.;
Madan, C. Synlett 2001, 5, 783; (b) Yadav, J.S.; Subba Reddy, B.V.;
Venkateshwara, C.; Shrinivasa, R. Synlett 2002, 6, 993; (c) Bandgar, B.P.;
Sadavarte, V.S.; Uppalla, L.S. Synlett 2001, 8, 1338; (d) Yadav, J.S.;
Subba Reddy, B.V.; Srinivasa, R.; Venugopal, C.; Ramalingam, T.
Synthesis 2001, 9, 1341; (e) Yadav, J.S.; Reddy, B.V.S.; Reddy, P.S.R.;
Shesha Rao, M. Tetrahedron Lett. 2002, 43, 6245.
Received in India August 28, 2003

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