Magnetically separable CuFe2O4 nanoparticles catalyzed ligand-free C-S coupling in water: Access to (E)- and (Z)-styrenyl-, heteroaryl and sterically hindered aryl sulfides

Article abstract of DOI:10.1002/adsc.201300261

An efficient coupling of styrenyl, heteroaryl and sterically hindered aryl halides with aryl- and heteroarylthiols catalyzed by the bimetallic Cu and Fe nanomaterial, CuFe2O4, in water in the presence of tetrabutylammonium bromide and potassium phosphate (K3PO4) has been achieved without using any ligand. A series of unsymmetrical functionalized (E)- and (Z)-styrenyl aryl, heteroaryl heteroaryl and sterically hindered aryl aryl sulfides has been obtained by this procedure. The compounds are obtained in high yields and excellent stereoselectivity has been observed for styrenyl sulfides. The catalyst can be easily separated by an external magnet and recycled for ten times without any appreciable loss of activity. This procedure provides an easy access to useful and challenging biologically active organosulfides which are difficult to achieve by other methods.

Full text of DOI:10.1002/adsc.201300261

FULL PAPERS
DOI: 10.1002/adsc.201300261
Magnetically Separable CuFe2O4 Nanoparticles Catalyzed Ligand-
À
Free C S Coupling in Water: Access to (E)- and (Z)-Styrenyl-,
Heteroaryl and Sterically Hindered Aryl Sulfides
Debasish Kundu,a Tanmay Chatterjee,a and Brindaban C. Ranua,*
a
Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata – 700032, India
Fax : (+91)-33-2473-2805; phone: (+91)-33-2473-4971; e-mail: ocbcr@iacs.res.in
Received: April 1, 2013; Revised: July 1, 2013; Published online: && &&, 0000
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/adsc.201300261.
Abstract: An efficient coupling of styrenyl, heteroar- has been observed for styrenyl sulfides. The catalyst
yl and sterically hindered aryl halides with aryl- and can be easily separated by an external magnet and
heteroarylthiols catalyzed by the bimetallic Cu and recycled for ten times without any appreciable loss
Fe nanomaterial, CuFe2O4, in water in the presence of activity. This procedure provides an easy access to
of tetrabutylammonium bromide and potassium useful and challenging biologically active organosul-
phosphate (K3PO4) has been achieved without using fides which are difficult to achieve by other methods.
any ligand. A series of unsymmetrical functionalized
À
(E)- and (Z)-styrenyl aryl, heteroaryl heteroaryl and Keywords: C S cross coupling; CuFe2O4 nanoparti-
sterically hindered aryl aryl sulfides has been ob- cles catalyst; reactions in water; (E)- and (Z)-styren-
tained by this procedure. The compounds are ob- yl sulfides; S-styrylation/vinylation; thiols; unsym-
tained in high yields and excellent stereoselectivity metrical heteroaryl sulfides
Introduction
cedures.[10] Thus, our objective is to find an efficient
general procedure for the coupling of both isomers of
The aryl carbon-sulfur bond-forming reaction is of styrenyl halides, heteroaryl halides, and sterically
much importance because of the useful applications challenging aryl halides with thiols using an inexpen-
of organosulfides as pharmaceutically active agents, sive and recyclable metal catalyst in an environmen-
organic materials and intermediates in organic synthe- tally acceptable reaction medium.
sis.[1] A number of aryl sulfides has been employed
Reactions in water have attracted considerable in-
for the treatment of cancer,[2] Alzheimerꢀs and Parkin- terest because of their environmental acceptability
sonꢀs diseases,[3] and HIV.[4] The styrenyl sulfides are and low cost.[11] Moreover, water often exhibits
also of much interest as these compounds have poten- unique reactivity and selectivity that cannot be ach-
tial utility against drug-resistant strains of tuberculosis ieved using other solvents.[12] Thus water is our obvi-
and anthrax.[5] In addition, the styrenyl or vinyl sul- ous choice as reaction medium.
fides, in general, are used as important intermediates
In recent times, interest in nanoparticle catalysis
in organic synthesis.[6] Thus the efficient synthesis of has increased tremendously because of its high effi-
these molecules is of considerable interest. The metal- ciency and compatibility with eco-friendly reaction
catalyzed aryl C S bond formation via a cross-cou- media.[13] The use of relatively benign and inexpensive
À
pling reaction of a halide and thiol promoted by Pd, Cu and Fe metal nanoparticles has received much at-
Ni, Co, Fe and Cu catalyst is the most common and tention in catalysis.[14] A bimetallic Cu and Fe nano-
effective.[7] Although several procedures have been material, CuFe2O4, has emerged as an efficient cata-
reported for the preparation of aryl sulfides,[8] the syn- lyst for a variety of reactions.[15] This has also been
theses of styrenyl sulfides are very limited.[9] More- used for the cross-coupling of aryl halides and thiols
over, the reactions with both isomers (cis and trans) in DMSO at 1008C[15a] and in 1,4-dioxane at reflux[15b]
of styrenyl halides by the same protocol were rarely for 24 h. Regarding the synthesis of styrenyl sulfides,
addressed.[9d] On the other hand, the reactions of het- the reactions of styrenyl halides (only trans) have
eroaryl halides and heteroaryl thiols are reported been addressed using CuI in DMSO or NMP in the
scarcely (only one example) among the existing pro- presence of a base and ligand,[9b,d,c] and CuBr in
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Table 1. Standardization of reaction conditions.
À
Scheme 1. CuFe2O4 catalyzed C S bond formation in water.
[bmim]BF4 in the presence of proline and K2CO3.[9a]
The synthesis of (Z)-vinyl sulfides has been reported
using CuI in an amino acid-based ionic liquid.[9d] Con-
sidering the importance and challenge for the synthe-
sis of these organosulfides we report here a CuFe2O4
nanoparticle-catalyzed coupling of styrenyl, heteroar-
yl, and sterically hindered aryl halides with aromatic
and heteroaromatic thiols in water in the presence of
tetrabutylammonium bromide (TBAB) without any
ligand (Scheme 1).
Results and Discussion
To standardize the reaction conditions, a series of ex-
periments was performed with variation of different
reaction parameters such as solvent, additive, temper-
ature, time and base for a representative coupling re-
action of (E)-4-methylstyrenyl bromide and 4-me-
thoxythiophenol.The results are summarized in
Table 1. Best yield was obtained using water in the
presence of TBAB and K3PO4 at 1008C (Table 1,
entry 3). The reaction did not proceed virtually at
room temperature even after
a longer period
(Table 1, entry 5). The other benign solvents such as
PEG-400, PEG-600 also furnished comparable results
(Table 1, entries 12–14). Tetrabutylammonium fluo-
ride (TBAF) and tetrabutylammonium hydroxide
(TBAH) (Table 1, entries 15 and 16) also worked
equally well. However, TBAB was chosen as being
less expensive. K3PO4 as a base provided better re-
sults than K2CO3 and KOH under similar conditions.
Thus, considering the operational simplicity and
[a]
Yields of isolated products.
A series of diversely substituted styrenyl halides
cost, H2O in combination with TBAB, K3PO4 at (bromides and iodides) underwent reactions with sev-
1008C was accepted as the general procedure. eral substituted thiophenols to produce the corre-
In a typical experimental procedure a mixture of sponding functionalized unsymmetrical styrenyl aryl
the halide (styrenyl, heteroaryl and aryl), thiol (aryl sulfides. The results are summarized in Table 2. Signif-
and heteroaryl) in water was heated at 1008C with icantly, the (E)-styrenyl halides provided the (E)-styr-
stirring in the presence of CuFe2O4 nanoparticles enyl sulfides and (Z)-halides produced (Z)-sulfides
(10 mol%), TBAB and K3PO4 for the specific period stereoselectively except in one reaction of fluoro-sub-
of time as required to complete the reaction (TLC). stituted (Z)-styrenyl bromide (Table 2, entry 9), which
Extraction of the reaction mixture with ethyl acetate furnished (Z)- and (E)- isomers in a 9:1 ratio. Both
followed by evaporation of solvent and column chro- styrenyl bromides and iodides gave uniformly high
matography provided the pure product. The catalyst yields and stereoselectivity. Interestingly, when the
was separated easily by a magnetic rod and was thiols were allowed to react with the styrenyl bro-
reused for subsequent reactions.
mides bearing the other halo groups (I/Br) they un-
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Magnetically Separable CuFe2O4 Nanoparticles Catalyzed Ligand-Free C S Coupling in Water
Table 2. Stereoselective S-styrylation/vinylation by CuFe2O4 NPs.
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Table 2. (Continued)
[a]
[b]
Reaction conditions: thiols (1.0 mmol), styryl or vinyl halides (1.0 mmol), CuFe2O4 (10 mol%), K3PO4
(1.5 mmol), TBAB (1 mmol), H2O (4 mL), 1008C, under argon atmosphere; isolated yields.
2.0 mmol of thiol was used.
derwent selective coupling with the Br at the styrenyl yl, quinolinyl, pyridinyl and thiazolyl units underwent
position (Table 2, entries 5, 6, 10 and 11). This might reactions with substituted heteroaryl thiols bearing
be due to the inherent nature of the catalytic system pyridinyl, furanyl, benzothiazolyl moeties to produce
giving high selectivity. This procedure offers an easy the corresponding unsymmetrical heteroaryl heteroar-
access to (Z)-styrenyl heteroaryl sulfides (Table 2, yl sulfides. The results are reported in Table 3. The
entry 12). The (E,E)-4-phenylbut-1,3-dienyl bromide bromo-substituted aryl and heteroaryl thiols reacted
reacted with a hindered 2,6-dimethylthiophenol with with the heteroaryl halides giving the desired sulfides
complete stereoselectivity to provide the correspond- (Table 3, entries 1 and 6) without any intermolecular
À
ing sulfide (Table 2, entry 13). The 1,3-bis[(E)-2-bro- Br SH coupling of bromothiols. It may be mentioned
movinyl]benzene underwent facile reaction with hin- that the Br group in the aromatic ring bearing the SH
dered 2,6-dimethylthiophenol leading to 1,3-bis{(E)-2- functionality is less reactive compared to the Br
[2,6-dimethylphenylthio]vinyl}benzene
(Table 2, group on the aryl halide counterpart because of the
entry 14) which might be of interest. The aliphatic high electron density in the thiol ring. This is support-
vinyl bromides (Table 2, entries 15 and 16) reacted ed by a blank reaction of 4-bromothiophenol under
with the aryl and heteroaryl thiols without any diffi- the identical reaction conditions providing the disul-
culty while retaining their stereoselectivities. A reac- fide only due to dimerization. 2-Mercaptopyridine on
tion of geminal alkenyl bromide (Table 2, entry 17) reaction with 2,5-dibromothiazole (Table 3, entry 8)
also produced an excellent result.
produced the corresponding diheteroaryl sulfide by
In general, several functionalized (Cl, Br, F, I, selective coupling with the Br at the 2-position. This
OMe) (E)- and (Z)-styrenyl halides participated in is obvious as the Br at the 2-position flanked between
this coupling reaction with different substituted thiols N and S is certainly more reactive, being more elec-
to produce a library of stereo-pure functionalized un- trophilic than the Br at the 5-position. The bromides
symmetrical styrenyl aryl or heteroaryl sulfides.
as well as iodides participated in this reaction. The di-
This procedure is also equally efficient for the cou- heteroaryl sulfides are of much importance for having
pling of heteroaryl halides and heteroaryl thiols, significant activities as herbicides,[16a] receptor antago-
which was rarely addressed earlier.[10] Several diverse- nists[16b] and antibacterial agents.[16c] This procedure
ly substituted heteroaryl halides containing thiophen- provides an easy access to these useful molecules.
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Magnetically Separable CuFe2O4 Nanoparticles Catalyzed Ligand-Free C S Coupling in Water
Table 3. Synthesis of unsymmetrical heteroaryl sulfides.
[a]
Reaction conditions: thiols (1.0 mmol), heteroaryl or aryl halides (1.0 mmol), CuFe2O4 (10 mol%), K3PO4
(1.5 mmol), TBAB (1 mmol), H2O (4 mL), 1008C, under argon atmosphere; isolated yields.
We also investigated the reactions of several steri-
The reactions of aryl dihalides with thiols and di-
cally hindered aryl halides and thiols (Table 4). Usual- thiols were also studied. The results are summarized
ly, these are very difficult to achieve by existing meth- in Table 5. Several acyclic and cyclic bis-sulfides
ods. Using this procedure we have been able to ac- (Table 5, entries 1–4) were obtained by this reaction.
complish the coupling of 2,6-dimethoxyiodobenzene The coupling of 1,2-diiodo-5-methylbenzene and 2-
and 2,6-dimethylthiophenol (Table 4, entry 1), 2,6-di- pyridinylthiol
provided
thio]pyridine (Table 5, entry 1). Similar-
ly, a number of bis-sulfides was obtained by this reac-
2-[4-methyl-2-(pyridin-2-
methoxyiodobenzene
(Table 4, entry 3).
and
4-methoxythiophenol ylthio)phenylACHUTNGTRENNUNG
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Table 4. Synthesis of sterically hindered diaryl sulfides.
[a]
Reaction conditions: thiols (1.0 mmol), aryl halides (1.0 mmol), CuFe2O4 (10 mol%), K3PO4
(1.5 mmol), TBAB (1 mmol), H2O (4 mL), 1008C, under argon atmosphere; isolated yields.
Table 5. Synthesis of bis-sulfides.
[a]
Reaction conditions: thiols (1.0 mmol), aryl halides (1.0 mmol), CuFe2O4 (10 mol%), K3PO4
(1.5 mmol), TBAB (1 mmol), H2O (4 mL), 1008C, under argon atmosphere; isolated yields.
2.0 mmol of thiol were used.
[b]
tion. One of these products (Table 5, entry 4) has
In general, all these reactions are clean and high
much potential as
a
promising drug against yielding. The products were obtained very pure after
a simple column chromatography. The majority of
thrombocytoACHTUNGTRENNUNG
penia.[16d]
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plishment of this thiolation reaction successfully in
water in the presence of tetrabutylammonium bro-
mide (TBAB) is of much significance in the context
of the earlier reports of no reaction in water.[15] In ad-
dition, our procedure has marked distinction to a re-
lated work reported earlier[15a] providing better effi-
ciency, shorter reaction period (12 h vs. 24 h) and high
selectivity in coupling with styrenyl and vinyl halides.
The reactions of sterically hindered substrates, cou-
pling of heteroaryl thiols and vinyl and styrenyl hal-
ides were not addressed there.[15a]
The TEM (Figure 2) and SEM (scanning electron
microscope) (Figure 3) images of the fresh and recov-
ered catalyst after the 4th cycle show that the mor-
phology of the catalyst remained unaltered. The XRD
pattern of the catalyst, CuFe2O4 before reaction (Fig-
ure 4a) and after the reaction in the 4th cycle (Fig-
ure 4b) and 8th cycle (Figure 4c) showed that the Cu
remains in the +2 oxidation state. Thus we suggest
that the reaction is proceeding through a usual oxida-
Figure 1. Recyclability chart of the catalyst.
these products are new and are being reported for the tive addition and reductive elimination pathway.[15a ]
first time with full characterization data. The reac-
tions of styrenyl halides are highly stereoselective fur-
nishing (E)-styrenyl sulfides from (E)-halides and Conclusions
(Z)-styrenyl sulfides from the (Z)-isomers. Several
functional groups such as F, Cl, Br, OMe are compati- The present procedure using CuFe2O4 nanoparticles
ble with this reaction. The CuFe2O4 catalyst is easily provides a very efficient and convenient methodology
separated magnetically and was recycled up to ten for the synthesis of unsymmetrical styrenyl, heteroaryl
times with only marginal loss of activity (Figure 1) and sterically hindered aryl sulfides by a simple reac-
due to inherent tendency of agglomeration of nano- tion of styrenyl/hetACTHNUGRTNEUNGeroaryl/aryl halides and aryl/heter-
particles in each exposure as indicated by TEM oaryl thiols in water in the presence of tetrabutylam-
(transmission electron microscope) images of the cat- monium bromide and K3PO4. The notable advantages
alyst after the fourth cycle (Figure 2). The accom- offered by this procedure are operational simplicity,
Figure 2. TEM image of the fresh catalyst (left). TEM image of the catalyst after 4th cycle (right).
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Figure 3. SEM image of the fresh catalyst (left). SEM image of the catalyst after 4th cycle (right).
general applicability, compatibility with different Recycling of the Catalyst
functional groups and sensitive units like furan, excel-
After completion of the reaction the magnetic bar covered
with the used catalyst was collected by a magnetic rod and
the bar was successively washed with ethanol and acetone
before being used for the next cycle of reaction.
lent stereoselectivity leading to both (E)- and (Z)-
styrenyl sulfides, and high yields of products. In addi-
tion, the use of inexpensive and benign CuFe2O4
nanoparticle as catalyst, reaction in water and recycla-
T0his procedure was followed for all the reactions in
bility of the catalyst up to ten times without apprecia- Table 2, Table 3, Table 4 and Table 5. A few of these prod-
ucts are known compounds (see the references in the tables)
and were easily identified by comparison of their spectro-
scopic data with those previously reported. The products
which are not reported earlier were characterized by their
ble loss of activity make this procedure more cost ef-
fective, sustainable and greener.
1
IR, H NMR and 13C NMR spectroscopic data and elemen-
tal analysis or HR-MS data. These are provided below in
order of their entries in respective tables.
Experimental Section
(Z)-(4-Methylstyryl)(4-methoxyphenyl)sulfane (Table 2,
entry 2): Yellow oil; IR (neat): n=3025, 1590, 1494, 1450,
1
732 cmÀ1; H NMR (500 MHz, CDCl3): d=2.40 (s, 3H), 3.83
General Procedure for Thiolation Reaction;
Representative Procedure for the Reaction of 4-
Methyl-trans-styrenyl Bromide with 4-Methoxy-
thiophenol (Table 2, entry 1)
(s, 3H), 6.38 (d, J=10.5 Hz, 1H), 6.5 (d, J=10.5 Hz, 1H),
6.92 (d, J=7 Hz, 2H), 7.23 (d, J=8 Hz, 2H), 7.44–7.47 (m,
4H); 13C NMR (125 MHz, CDCl3): d=21.4, 55.5, 114.9
(2C), 125.9, 127.2, 129.1 (2C), 129.2 (2C), 131.8, 132.9 (2C),
134.0, 136.9, 159.5; anal. calcd. for C16H16OS: C 74.96, H
6.29; found: C 74.88, H 6.20%.
A
mixture of 4-methyl-trans-styrenyl bromide (195 mg,
1.0 mmol), 4-methoxythiophenol (140 mg, 1 mmol), CuFe2O4
nanoparticles (24 mg, 0.1 mmol), K3PO4 (318 mg, 1.5 mmol)
and TBAB (321 mg, 1.0 mmol) in water (4 mL) was heated
at 1008C under stirring for 12 h (TLC). The reaction mix-
ture was allowed to cool to room temperature without being
stirred and during this period all the CuFe2O4 nanoparticles
were accumulated on the stirring bar which was separated
out. The mixture was extracted with ethyl acetate and the
extract was evaporated to give the crude product which was
purified by column chromatography to provide the product,
(E)-(4-methylstyryl)(4-methoxyphenyl)sulfane as a viscous
liquid; yield: 235.8 mg (92%), IR (neat): n=2936, 2835,
(Z)-(4-Chlorostyryl)(2,6-dimethylphenyl)sulfane (Table 2,
entry 4): Viscous colourless liquid; IR (neat) n=3054, 2974,
1
1592, 1488, 722 cmÀ1; H NMR (500 MHz, CDCl3): d=2.52
(s, 6H), 6.03 (d, J=10.5 Hz, 1H), 6.41 (d, J=10.5 Hz, 1H),
7.16–7.21 (m, 3H), 7.38 (d, J=8.5 Hz, 2H), 7.55 (d, J=
8.5 Hz, 2H); 13C NMR (125 MHz, CDCl3): d=22.2 (2C),
124.3 (2C), 126.7, 128.5 (2C), 128.6 (2C), 128.8, 129.1, 129.4,
130.1 (2C), 135.5, 142.5; HR-MS: m/z=275.0625, calcd. for
C16H15ClS [M+H]+: 275.0656.
(Z)-(4-Bromostyryl)(4-methoxyphenyl)sulfane (Table 2,
entry 5): Colourless viscous liquid; IR (neat): n=2962, 1589,
1488, 820 cmÀ1 1H NMR (500 MHz, CDCl3): d=3.82 (s,
;
1615, 832 cmÀ1 1H NMR (500 MHz, CDCl3): d=2.34 (s,
;
3H), 6.39 (d, J=10.5 Hz, 1H), 6.44 (d, J=10.5 Hz, 1H),
6.89–6.90 (m, 2H), 7.37–7.43 (m, 4H), 7.50 (d, J=8.5 Hz,
2H); 13C NMR (125 MHz, CDCl3): d=55.5, 115.1 (2C),
120.8, 124.6, 126.5, 129.6, 130.3 (2C), 131.5 (2C), 133.2 (2C),
135.7, 159.8; anal. calcd. for C15H13BrOS: C 56.08, H 4.08;
found: C 56.23, H 4.18%.
3H), 3.83 (s, 3H), 6.54 (d, J=15 Hz, 1H), 6.78 (d, J=15 Hz,
1H), 6.91 (d, J=8 Hz, 2H), 7.11 (d, J=8 Hz, 2H), 7.12 (d,
J=8 Hz, 2H), 7.41 (d, J=8 Hz, 2H); 13C NMR (125 MHz,
CDCl3): d=21.3, 55.5, 115.0 (2C), 124.4, 125.9 (2C), 129.1,
129.5, 129.7 (2C), 133.0 (2C), 133.3, 137.2 159.5; anal. calcd.
for C16H16OS: C 74.96, H 6.29; found C 74.91, H 6.25%.
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(s, 6H), 6.04 (d, J=11 Hz, 1H), 6.39 (d, J=11 Hz, 1H),
7.14–7.23 (m, 3H), 7.47 (d, J=8.5 Hz, 2H), 7.52 (d, J=
8.5 Hz, 2H); 13C NMR (125 MHz, CDCl3): d=22.2 (2C),
120.5, 124.3, 128.5 (2C), 129.1 (2C), 129.7, 130.4 (2C), 131.5
(2C), 133.6, 135.9, 142.5; HR-MS: m/z=319.0156, calcd. for
C16H15BrS [M+H]+: 319.0151.
(E)-(4-Fluorostyryl)(4-methoxyphenyl)sulfane
(Table 2,
entry 8): White solid, mp 62–648C; IR (KBr): n=3020,
1
2842, 1595, 1492 cmÀ1; H NMR (500 MHz, CDCl3): d=3.82
(s, 3H), 6.46 (d, J=15 Hz, 1H), 6.74 (d, J=15 Hz, 1H),
6.89–6.99 (m, 4H), 7.23–7.26 (m, 2H), 7.39–7.42 (m, 2H);
13C NMR (125 MHz, CDCl3): d=55.5, 115.0–115.7 (m, 2C),
124.7 (d, J=38.7 Hz, 2C), 125.6, 127.4 (d, J=7.5 Hz, 2C),
127.9 (d, J=21.25 Hz, 2C), 130.5 (d, J=7.5 Hz), 133.1, 133.7
(2C), 159.8, 162.9 (d, J=245 Hz); anal. calcd. for
C15H13FOS: C 69.21, H 5.03; found: C 69.30, H 5.12%.
(4-Fluorostyryl)(2,6-dimethylphenyl)sulfane (Z:E=90:10)
(Table 2, entry 9): Colourless liquid; IR (neat): n=3054,
2951, 2924, 1507, 1228 cmÀ1 1H NMR (500 MHz, CDCl3):
;
d=2.48 (s, 6H), 5.94 (d, J=11 Hz, 1H), 6.40 (d, J=11 Hz,
1H), 7.06–7.17 (m, 5H), 7.54–7.57 (m, 2H); 13C NMR
(125 MHz, CDCl3): d=21.8, 22.2, 114.9–115.6 (m), 124.3 (d,
J=26 Hz), 127.0 (d, J=7 Hz), 128.1–128.5 (m), 128.9, 129.0,
129.4, 130.4, 130.9, 131.3, 132.7, 142.6, 143.5, 161.9 (d, J=
237.5 Hz); anal. calcd. for C16H15FS: C 74.38, H 5.85; found:
C 74.42, H 5.96%.
(E)-(2-Iodostyryl)(2,6-dimethylphenyl)sulfane
(Table 2,
entry 10): White solid, mp 58–608C; IR (KBr): n=3055,
1
2970, 1581, 1456, 742 cmÀ1; H NMR (500 MHz, CDCl3): d=
2.57 (s, 6H), 6.13 (d, J=15 Hz, 1H), 6.61 (d, J=15 Hz, 1H),
6.83–6.86 (m, 1H), 7.22–7.37 (m, 4H), 7.36 (d, J=7.5 Hz,
1H), 7.76 (d, J=7.5 Hz, 1H); 13C NMR (125 MHz, CDCl3):
d=21.8 (2C), 99.0, 125.8, 127.8, 128.1, 128.4, 128.6 (2C),
128.8, 129.3, 129.6 (2C), 139.5, 140.2, 143.5; anal. calcd. for
C16H15IS: C 52.47, H 4.13; found: C 52.41, H 4.24%.
4-((E)-4-Bromostyrylthio)benzenamine
entry 11): Brown solid, mp 83–858C; IR (KBr): n=3446,
3365, 1618, 1589, 1498, 831 cmÀ1 1H NMR (500 MHz,
(Table 2,
;
CDCl3): d=3.75 (broad, 2H), 6.30 (d, J=15.5 Hz, 1H), 6.68
(d, J=8.5 Hz, 2H), 6.83 (d, J=15.5 Hz, 1H), 7.11 (d, J=
8.5 Hz, 2H), 7.29 (d, J=8.5 Hz, 2H), 7.38 (d, J=8.5 Hz,
2H); 13C NMR (125 MHz, CDCl3): d=115.9 (2C), 120.6,
126.0, 127.3 (2C), 128.3, 131.8 (2C), 134.6 (3C), 136.0,
147.0; HR-MS: m/z=305.9922, calcd. for C14H12BrNS [M+
H]+: 305.9947.
(Z)-(4-Methylstyryl)(2-pyridinyl)sulfane
entry 12): Brown oil; IR (neat): n=3082, 2978, 1582,
1480 cmÀ1 1H NMR (500 MHz, CDCl3): d=2.29 (s, 3H),
(Table 2,
;
6.65 (d, J=11 Hz, 1H), 6.99–7.01 (m, 1H), 7.12 (d, J=8 Hz,
2H), 7.17–7.23 (m, 4H), 7.35 (d, J=7.5 Hz, 2H), 7.48 (d, J=
7.5 Hz, 1H), 8.44 (d, J=3.5 Hz, 1H); 13C NMR (125 MHz,
CDCl3): d=21.4, 119.2, 120.6, 122.9, 125.9, 127.7, 128.9
(2C), 129.2 (2C), 136.6, 137.2, 149.9, 150.0; anal. calcd. for
C14H13NS: C 73.97, H 5.76, N 6.16; found: C 73.88, H 5.64,
N 6.23%.
Figure 4. XRD of fresh catalyst (top). XRD of the catalyst
after 4th cycle (middle). XRD of the catalyst after 8th cycle
(bottom).
(2,6-Dimethylphenyl)
sulfane (Table 2, entry 13): Light green liquid; IR (neat): n=
2961, 2902, 1586, 1247 cmÀ1 1H NMR (500 MHz, CDCl3):
ACHTUNGTRENN[UNG (1E,3E)-4-phenylbuta-1,3-dienyl]-
;
d=2.51 (s, 6H), 5.80–5.85 (dd, J1 =14.5 Hz, J2 =10.5 Hz,
1H), 6.27 (d, J=15.5 Hz, 1H), 6.31 (d, J=14.5 Hz, 1H),
6.73–6.79 (dd, J1 =15.5 Hz, J2 =10.5 Hz, 1H), 7.16–7.27 (m,
3H), 7.29–7.35 (m, 5H); 13C NMR (125 MHz, CDCl3): d=
(Z)-(4-Bromostyryl)(2,6-dimethylphenyl)sulfane (Table 2,
entry 6): White solid, mp 84–868C; IR (KBr): n=3423,
1
3049, 1652, 1483 cmÀ1; H NMR (500 MHz, CDCl3): d=2.50
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Debasish Kundu et al.
FULL PAPERS
21.8 (2C), 124.3, 126.2 (2C), 126.6, 128.0, 128.4 (2C), 128.5
(2C), 128.8 (2C), 129.1, 129.9, 132.8, 137.7, 143.4; anal.
calcd. for C18H18S: C 81.15, H 6.81; found: C 81.21, H
6.73%.
1-[5-(Pyridin-2-ylsulfanyl)-thiophen-2-yl]ethanone
(Table 3, entry 5): White solid, mp 68–708C; IR (KBr): n=
3080, 2987, 1652, 1558, 1415 cmÀ1 1H NMR (500 MHz,
CDCl3): d=2.54 (s, 3H), 7.04–7.08 (m, 2H), 7.30 (t, J=
4 Hz, 1H), 7.51–7.55 (m, 1H), 7.64–7.66 (m, 1H), 8.43 (d,
J=4.5 Hz, 1H); 13C NMR (125 MHz, CDCl3): d=26.9,
121.1, 121.6, 132.7, 136.2, 137.3, 139.0, 148.7, 149.9, 159.4,
190.2; HR-MS: m/z=236.0199, calcd. for C11H9NOS2 [M+
H]+: 236.0198.
;
1,3-Bis[(E)-2(2,6-dimethylphenylthio)vinyl]benzene
(Table 2, entry 14): White solid, mp 100–1028C; IR (KBr):
1
n=3049, 2975, 1581, 937 cmÀ1; H NMR (500 MHz, CDCl3):
d=2.49 (s, 12H), 5.90 (d, J=15.5 Hz, 2H), 6.65 (d, J=
15.5 Hz, 2H), 6.97–7.02 (m, 4H), 7.14–7.29 (m, 6H);
13C NMR (125 MHz, CDCl3): d=21.8 (4C), 122.9 (2C),
123.8 (2C), 124.9, 125.0 (4C), 128.5 (4C), 128.9 (2C), 129.4
(2C), 129.9, 137.4 (2C), 143.5 (2C); anal. calcd. for C26H26S:
C 77.56, H 6.51; found: C 77.48, H 6.58%.
1-[5-(5-Bromopyridin-2-ylsulfanyl)-thiophen-2-yl]ethan-
one (Table 3, entry 6): Pale yellow solid, mp 92–948C; IR
1
(KBr): n=3066, 1660, 1550, 1409, 1274, 802 cmÀ1; H NMR
(500 MHz, CDCl3): d=2.56 (s, 3H), 6.95 (d, J=8.5 Hz, 1H),
7.31 (d, J=3.5 Hz, 1H), 7.63–7.66 (m, 2H), 8.49 (s, 1H);
13C NMR (125 MHz, CDCl3): d=26.9, 117.8, 122.6, 132.6,
136.5, 138.0, 139.7, 149.1, 150.7, 158.1, 190.1; HR-MS: m/z=
313.9305, calcd. for C11H8BrNOS2 [M+H]+: 313.9303.
(4-Bromophenyl)(2-cyclohexylvinyl)sulfane (E:Z=60:40)
(Table 2, entry 15): Yellow liquid; IR (neat): n=2923, 2848,
1
1471, 1446, 808 cmÀ1; H NMR (300 MHz, CDCl3): d=1.16–
1.32 (m, 10H), 1.65–1.81 (m, 10H), 2.01–2.15 (m, 2H), 5.71–
5.77 (m, 1H), 6.01–6.05 (m, 3H), 7.14–7.21 (m, 4H), 7.39–
7.45 (m, 4H); 13C NMR (75 MHz, CDCl3): d=25.9 (2C),
26.1 (2C), 32.6 (2C), 32.7 (2C), 38.4 (2C), 41.6 (2C), 118.0,
119.8 (2C), 129.7 (2C), 130.1 (2C), 132.0 (2C), 132.1 (2C),
136.0, 136.3, 140.6, 144.5 (2C); HR-MS: m/z=297.0308,
calcd. for C14H18BrS [M+H]+: 297.0307.
2-(5-Bromothiazol-2-ylsulfanyl)pyridine (Table 3, entry 8):
Yellow viscous oil; IR (neat): n=3052, 2726, 1577,
1481 cmÀ1 1H NMR (500 MHz, CDCl3): d=7.16 (s, 1H),
;
7.31 (d, J=8 Hz, 1H), 7.62 (t, J=7 Hz, 1H), 7.71 (s, 1H),
8.52 (s, 1H); 13C NMR (125 MHz, CDCl3): d=111.3, 121.8,
123.1, 137.4, 143.9, 149.4, 155.1, 159.8; HR-MS: m/z=
272.9151, calcd. for C8H5N2S2 [M+H]+: 272.9150.
2-(Oct-1-enylthio)-5-bromopyridine
(Table 2, entry 16): Colourless liquid; IR (neat): n=2925,
2854, 1558, 1446, 1114 cmÀ1 1H NMR (300 MHz, CDCl3):
(E:Z=55:45)
1-[5-(2-Methylfuran-3-ylsulfanyl)thiophen-2-yl]ethanone
(Table 3, entry 10): Green oil; IR (neat): n=3146, 2999,
;
d=0.85–0.91 (m, 6H), 1.25–1.48 (m, 16H), 2.18–2.26 (m,
4H), 5.89–5.97 (m, 1H), 6.04–6.14 (m, 1H), 6.44–6.50
(m,1H), 6.65–6.69 (m, 1H), 7.04–7.12 (m, 2H), 7.59–7.64
(m, 2H), 8.48–8.50 (m, 2H); 13C NMR (75 MHz, CDCl3):
d=14.2 (2C), 22.7 (2C), 29.0 (2C), 29.9 (2C), 31.7 (2C),
33.4 (2C), 116.5, 116.6, 117.4, 118.3, 122.6, 123.3, 134.3 (2C),
138.8, 138.9, 150.6 (2C), 157.1, 158.4; HR-MS: m/z=
300.0417, calcd. for C13H19BrNS [M+H]+: 300.0416.
1653, 1410 cmÀ1 1H NMR (500 MHz, CDCl3): d=2.38 (s,
;
3H), 2.45 (s, 3H), 6.39 (d, J=1.5 Hz, 1H), 6.85 (d, J=
3.5 Hz, 1H), 7.33 (d, J=1.5 Hz, 1H), 7.47 (d, J=3.5 Hz,
1H); 13C NMR (125 MHz, CDCl3): d=108.7, 114.6, 126.2,
133.2, 141.6, 143.7, 150.5, 156.9, 189.7; HR-MS: m/z=
239.0156, calcd. for C11H10O2S2 [M+H]+: 239.0195.
(2,6-Dimethoxyphenyl)(2,6-dimethylphenyl)sulfane
(Table 4, entry 1): White solid; mp 102–1048C; IR (KBr):
3-[1-(2-Methylfuran-3-ylthio)-2-cyclohexylvinylthio]-2-
methylfuran (Table 2, entry 17): Yellow liquid; IR (neat):
n=3002, 2833, 1578, 1103 cmÀ1
;
1H NMR (500 MHz,
CDCl3): d=2.45 (s, 6H), 3.70 (s, 6H), 6.53 (d, J=8.5 Hz,
2H), 7.03–7.08 (m, 3H), 7.19 (t, J=8.5 Hz, 1H); 13C NMR
(125 MHz, CDCl3): d=21.7 (2C), 56.0 (2C), 104.5 (2C),
127.0, 127.7 (3C), 128.5, 134.4, 141.9 (2C), 160.0 (2C); anal.
calcd. for C16H18S: C 79.29, H 7.49; found: C 79.38, H
7.55%.
n=3142, 2994, 1472, 1446 cmÀ1
;
1H NMR (300 MHz,
CDCl3): d=1.05–1.33 (m, 4H), 1.58–1.72 (m, 6H), 2.13 (s,
3H), 2.23 (s, 3H), 2.35–2.38 (m, 1H), 5.62 (d, J=9.3 Hz,
1H), 6.25 (d, J=2.1 Hz, 1H), 6.28 (d, J=1.8 Hz, 1H), 7.26–
7.27 (m, 2H); 13C NMR (75 MHz, CDCl3): d=11.7, 11.9,
25.8, 32.8, 39.8, 44.1, 109.1, 109.3, 114.6, 114.9, 115.3, 128.3,
140.6, 140.8, 155.1, 155.3; HR-MS: m/z=335.1133, calcd. for
C18H23O2S2 [M+H]+: 335.1134.
2-(Thiophen-3-ylsulfanyl)phenylamine (Table 4, entry 2):
Red liquid; IR (neat): n=3361, 2920, 1608, 1477, 750 cmÀ1
;
1H NMR (500 MHz, CDCl3): d=4.21 (s, 2H), 6.63–6.80 (m,
2H), 6.80–6.84 (m, 2H), 7.10 (t, J=8.5 Hz, 1H), 7.17–7.21
(m, 1H), 7.35 (d, J=8 Hz, 1H); 13C NMR (125 MHz,
CDCl3): d=115.5, 116.5, 118.9, 121.2, 126.5, 128.2, 130.7,
132.0, 136.2, 148.1; HR-MS: m/z=208.0248, calcd. for
C10H9NS2 [M+H]+: 208.0249.
3-(Pyridin-2-ylsulfanyl)quinoline
Brown viscous liquid; IR (neat): n=3081, 2986, 1557,
1515 cmÀ1 1H NMR (500 MHz, CDCl3): d=7.00–7.02 (m,
(Table 3,
entry 3):
;
2H), 7.46 (t, J=8 Hz, 1H), 7.55 (t, J=8 Hz, 1H), 7.73 (t,
J=8 Hz, 1H), 7.78 (d, J=8 Hz, 1H), 8.10 (d, J=8.5 Hz,
1H), 8.36–8.38 (m, 2H), 8.93 (s, 1H); 13C NMR (125 MHz,
CDCl3): d=120.7, 122.0, 125.2, 127.4, 127.8, 128.3, 129.4,
130.5, 136.9, 141.8, 147.4, 149.9, 154.7, 159.3; anal. calcd. for
C14H10N2S: C 70.56, H 4.23, N 11.76; found: C 70. 52, H
4.32, N 11.65%.
2-Methoxy-1-(4-methoxyphenylsulfanyl)naphthalene
(Table 4, entry 4): White solid; mp 80–828C; IR (KBr): n=
2956, 2835, 1589, 1244 cmÀ1 1H NMR (500 MHz, CDCl3):
;
d=3.72 (s, 3H), 3.97 (s, 3H), 6.72 (d, J=9 Hz, 2H), 7.10 (d,
J=8.5 Hz, 2H), 7.34–7.40 (m, 2H), 7.52 (t, J=8.5 Hz, 1H),
7.82 (d, J=8 Hz, 1H), 7. 94 (d, J=9.5 Hz, 1H), 8.55 (d, J=
8.5 Hz, 1H); 13C NMR (125 MHz, CDCl3): d=55.4, 57.1,
113.7, 114.6 (2C), 124.2, 125.7, 127.7, 128.3 (2C), 128.9,
129.3 (2C), 129.7, 131.8, 136.3, 157.9, 159.1; anal. calcd. for
C18H16O2S: C 72.94, H 5.44; found: C 72.81, H 5.51%.
2-[4-Methyl-2-(pyridin-2-ylthio)phenylthio]pyridine
1-[5-(4-Methoxyphenylsulfanyl)thiophen-2-yl]ethanone
(Table 3, entry 4): Yellow oil; IR (neat): n=2958, 2883,
1650, 1412 cmÀ1 1H NMR (500 MHz, CDCl3): d=2.45 (s,
;
3H), 3.81 (s, 3H), 6.87–6.92 (m, 3H), 7.44–7.48 (m, 3H);
13C NMR (125 MHz, CDCl3); d=26.4, 55.5, 115.3 (2C),
124.2, 128.4, 133.0, 134.9 (2C), 144.5, 150.1, 160.6, 189.8;
anal. calcd. for C13H12O2S2: C 59.06, H 4.58; found: C 59.14,
H 4.45%.
(Table 5, entry 1): Yellow oil; IR (neat): n=3081, 2986,
1556 cmÀ1 1H NMR (500 MHz, CDCl3): d=2.34 (s, 3H),
;
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Magnetically Separable CuFe2O4 Nanoparticles Catalyzed Ligand-Free C S Coupling in Water
6.92–6.99 (m, 4H), 7.19 (d, J=8.0 Hz, 1H), 7.39–7.45 (m,
2H), 7.48 (s, 1H), 7.57 (d, J=8.0 Hz, 1H), 8.35–8.38 (m,
2H); 13C NMR (125 MHz, CDCl3): d=21.2, 120.1, 120.4,
122.1, 122.9, 130.8, 132.5, 136.3, 136.4, 136.7, 136.8 (2C),
140.4, 149.6, 149.7, 159.8, 165.4; anal. calcd. for C17H14N2S2:
C 65.77, H 4.55, N 9.02; found: C 65.68, H 4.61, N 9.10%.
2-[5-(Pyridin-2-ylthio)thiazol-2-ylthio]pyridine (Table 5,
entry 4): Brown viscous oil; IR (neat): n=2922, 1557, 1415,
1051 cmÀ1. 1H NMR (500 MHz, CDCl3): d=6.98–7.01 (m,
2H), 7.14 (t, J=6 Hz, 1H), 7.37 (d, J=8 Hz, 1H), 7.48 (t,
J=7.5 Hz, 1H), 7.60 (d, J=7.5 Hz, 1H), 7.89 (s, 1H), 8.36
(d, J=4 Hz, 1H), 8.50 (d, J=3.5 Hz, 1H); 13C NMR
(125 MHz, CDCl3): d=120.7, 122.0, 123.7, 126.0, 137.1,
137.3, 149.4, 149.5 (3C), 154.5, 159.4, 165.4; HR-MS: m/z=
304.0030, calcd. for C13H9N3S3 [M+H]+: 304.0031.
Miyaura) Springer-Verlag, Berlin, Germany, 2001, 219,
pp 131–209; b) J. F. Hartwig, Angew. Chem. 1998, 110,
2154–2177; Angew. Chem. Int. Ed. 1998, 37, 2046–2067.
[8] a) T. Kondo, T. Q. Mitsudo, Chem. Rev. 2000, 100,
3205–3220; b) M. A. Fernandez-Rodriguez, Q. Shen,
J. F. Hartwig, J. Am. Chem. Soc. 2006, 128, 2180–2181;
c) T. Itoh, T. Mase, Org. Lett. 2004, 6, 4587–4590;
d) Y. J. Chen, H. H. Chen, Org. Lett. 2006, 8, 5609–
5612; e) C. G. Bates, R. K. Gujadhur, D. Venkatarama-
na, Org. Lett. 2002, 4, 2803–2806; f) Y. C. Wong, T. T.
Jayanth, C. H. Chen, Org. Lett. 2006, 8, 5613–5616, and
references cited therein.
[9] a) Y. Zheng, X. Du, W. Bao, Tetrahedron Lett. 2006, 47,
1217–1220; b) R. S. Xu, L. Yue, Y. J. Pan, Tetrahedron
2012, 68, 5046–5052; c) Z. Wang, H. Mo, W. Bao, Syn-
lett 2007, 91–94; d) W. Bao, Y. Liu, Z. Lv, Synthesis
2008, 1911–1917; e) M. S. Kabir, M. Lorenz, M. L. Van
Linn, O. A. Namjoshi, S. Ara, J. M. Cook, J. Org.
Chem. 2010, 75, 3626–3643.
Acknowledgements
[10] S. Kovacs, Z. Novak, Org. Biomol. Chem. 2011, 9, 711–
716.
We gratefully acknowledge the financial support from CSIR,
New Delhi [Grant no. 01ACTHNUTRGNEU(GN 2365)/2010/EMR-II)] and DST,
New Delhi for the J. C. Bose Fellowship to Brindaban C.
Ranu (Grant no. SR/S2/JCB-11/2008). Debasish Kundu and
Tanmay Chatterjee thank CSIR, New Delhi for their fellow-
ships.
[11] a) C.-J. Li, T. H. Chan, Organic Reactions in Aqueous
Media, Wiley, New York, 1997; b) Organic Synthesis in
Water, (Ed.: P. A. Grieco), Blackie Academic and Pro-
fessional, London, 1998; c) C.-J. Li, Chem. Rev. 2005,
105, 3095–3166.
[12] a) N. Azizi, M. R. Saidi, Org. Lett. 2005, 7, 3649–3651;
b) G. L. Khatik, R. Kumar, A. K. Chakraborti, Org.
Lett. 2006, 8, 2433–2436; c) B. C. Ranu, S. Banerjee,
Tetrahedron Lett. 2007, 48, 141–143; d) B. C. Ranu, T.
Mandal, Synlett 2007, 925–928.
[13] a) D. Astruc, Inorg. Chem. 2007, 46, 1884–1894; b) D.
Astruc, F. Lu, J. R. Aranzaes, Angew. Chem. 2005, 117,
8062–8083; Angew. Chem. Int. Ed. 2005, 44, 7852–7872;
c) I. P. Beletskaya, A. V. Cheprakov, Chem. Rev. 2000,
100, 3009–3066.
References
[1] a) D. N. Jones, in: Comprehensive Organic Chemistry,
(Eds.: D. H. Barton, D. W. Ollis), Pergamon, New
York, 1979, Vol. 3; b) D. J. Procter, J. Chem. Soc.
Perkin Trans. 1 2001, 335–354; c) S. V. Ley, A. W.
Thomas, Angew. Chem. 2003, 115, 5558–5607; Angew.
Chem. Int. Ed. 2003, 42, 5400–5449; d) C. M. Rayner,
Contemp. Org. Synth. 1996, 3, 499–533; e) M. Tiecco,
Synthesis 1988, 749–759.
[2] G. De Martino, M. C. Elder, G. La Regina, A. Cosuc-
cia, M. C. Berbera, D. Barrow, R. I. Nicholson, G.
Chiosis, A. Brancale, E. Hamei, M. Artico, R. Silvestri,
J. Med. Chem. 2006, 49, 947–954.
[3] a) S. F. Nielsen, E. O. Neilsen, G. M. Olsen, T. Liljefors,
D. Peters, J. Med. Chem. 2000, 43, 2217–2226; b) G.
Liu, J. R. Huth, E. T. Olejniczak, R. Mendoza, P. Dev-
ries, S. Leitza, E. B. Reilly, G. F. Okasinski, S. W. Fesik,
T. W. von Geldern, J. Med. Chem. 2001, 44, 1202–1210.
[4] S. W. Kaldor, V. J. Kalish, J. F. Devies II, B. V. Shetty,
J. E. Fritz, K. Appelt, J. A. Burgess, K. M. Campanale,
N. Y. Chirgadze, D. K. Clawsor, B. A. Dressman, S. D.
Hatch, D. A. Khalil, M. B. Kosa, P. P. Lubbehusen,
M. A. Muesing, A. K. Patick, S. H. Reich, K. S. Su,
J. H. Tatlock, J. Med. Chem. 1997, 40, 3979–3985.
[5] A. Monte, M. S. Kabir, J. M. Cook, M. Rott, W. R.
Schwan, L. Deofe, U.S. Pat. Appl. Publ. 2007, 37.
[6] a) B. M. Trost, A. C. Lavoie, J. Am. Chem. Soc. 1983,
105, 5075–5094; b) V. G. Shukla, P. D. Salgaonkar, K. G.
Akamanchi, J. Org. Chem. 2003, 68, 5422–5425; c) E.
Baciocchi, M. F. Gerini, A. Lapi, J. Org. Chem. 2004,
69, 3586–3589.
[14] a) S. Bhadra, A. Saha, B. C. Ranu, Green Chem. 2008,
10, 1224–1230; b) L. Rout, T. K. Sen, T. Punniyamurthy,
Angew. Chem. 2007, 119, 5679–5682; Angew. Chem.
Int. Ed. 2007, 46, 5583–5586; c) S. Ahammed, A. Saha,
B. C. Ranu, J. Org. Chem. 2011, 76, 7235–7239; d) H. J.
Xu, Y. F. Liang, X. F. Zhou, Y. S. Feng, Org. Biomol.
Chem. 2012, 10, 2562–2568; e) A. Correa, C. Bolm,
Angew. Chem. 2007, 119, 9018–9021; Angew. Chem. Int.
Ed. 2007, 46, 8862–8865; f) S. Bhadra, S. Ahammed,
B. C. Ranu, Curr. Org. Chem. 2012, 16, 1453–1460.
[15] a) K. Swapna, S. N. Murthy, M. T. Jyothi, Y. V. D. Na-
geswar, Org. Biomol. Chem. 2011, 9, 5989–5996; b) N.
Panda, A. K. Jena, S. Mohapatra, Appl. Catal. A: Gen-
eral 2012, 433, 258–264; c) R. Zhang, J. Liu, S. Wang, I.
Niu, P. Xia, W. Sun, ChemCatChem 2011, 3, 146–149;
d) D. Kundu, N. Mukhejee, B. C. Ranu, RSC Adv. 2013,
3, 117–125.
[16] a) C. Lamberth, L. Quaranta, A. Edmunds, M. Pouliot,
S. Trah, PCT Int. Appl. WO 2012069601A1 20120531,
2002; b) N. S. Park, C. M. Churl, Y. S. Jung, J. I. Choi,
C. W. Lee, Y. J. Chung, S. W. Chung, S. W. Choi, J. Y.
Kong, W. K. Park, Eur. Pat. Appl. EP 869122A1
19981007, 1998; c) I. T. Barnish, P. E. Cross, R. P. Dick-
inson, British Patent GB 1459571A1 19761222, 1976;
d) M. Matsuo, T. Ogino, K. Tsuji; PCT Int. Appl. WO
9630370A2 19961003, 1996.
[7] a) A. R. Muci, S. L. Buchwald, in: Practical Palladium
À
À
Catalysts for C N and C O Bond Formation, (Ed.: N.
Adv. Synth. Catal. 0000, 000, 0 – 0
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FULL PAPERS
[17] a) K. Karunakaran, Oxidation Comm. 1998, 21, 519–
525; b) W. Lin, L. Chen, P. Knochel, Tetrahedron 2007,
63, 2787–2797; c) I. Nagasaki, M. Matsumoto, M. Ya-
mashita, A. Miyashita, Heterocycles 1999, 51, 1015–
1024; d) D. J. C. Prasad, G. Sekar, Org. Lett. 2011, 13,
1008–1011; e) M. T. Lan, W. Y. Wu, S. H. Huang, K. L.
Luo, F. Y. Tsai, RSc Adv. 2011, 1, 1751–1755; f) J. M.
Becht, C. Le Drian, J. Org. Chem. 2011, 76, 6327–6330;
g) B. Boduszek, H. J. Shine, T. K. Venkatachalam, J.
Org. Chem. 1989, 54, 1616–1626; h) J. Vicente, J. A.
Abad, R. M. Lopez-Nicolas, Tetrahedron 2008, 64,
6281–6288.
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Magnetically Separable CuFe2O4 Nanoparticles Catalyzed
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Ligand-Free C S Coupling in Water: Access to (E)- and
(Z)-Styrenyl-, Heteroaryl and Sterically Hindered Aryl
Sulfides
Adv. Synth. Catal. 2013, 355, 1 – 13
Debasish Kundu, Tanmay Chatterjee, Brindaban C. Ranu*
Adv. Synth. Catal. 0000, 000, 0 – 0
ꢁ 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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