Facile ring-expansion substitution reactions of 1,3-dithiolanes and 1,3-dithianes initiated by electrophilic reagents to produce monohalo-, -cyano-, -azido- and -thiocyanato-1,4-dithiins and -1,4-dithiepins

Article abstract of DOI:10.1002/ejoc.200400502

Mild and convenient methods for the high yielding ring-expansion substitution reactions of 1,3-dithiolanes and 1,3-dithianes generated from different aryl methyl ketones using different electrophilic reagents are reported. In this study, facile preparatio

Full text of DOI:10.1002/ejoc.200400502

FULL PAPER
Facile Ring-Expansion Substitution Reactions of 1,3-Dithiolanes
and 1,3-Dithianes Initiated by Electrophilic Reagents to Produce Monohalo-,
-cyano-, -azido- and -thiocyanato-1,4-dithiins and -1,4-dithiepins
Habib Firouzabadi,*[a] Nasser Iranpoor,*[a] Atefeh Garzan,[a] Hamid Reza Shaterian,[a] and
Farzaneh Ebrahimzadeh[a]
Keywords: Ring-expansion / Electrophilic substitution / 1,3-Dithiolane / 1,3-Dithiane / 1,4-Dithiin / 1,4-Dithiepin /
N-Halosuccinimide / N-Thiocyanatosuccinimide / N-Cyanosuccinimide / N-Azidosuccinimide
Mild and convenient methods for the high yielding ring-ex- anato-1,4-dithiins and -1,4-dithiepins are described. A gene-
pansion substitution reactions of 1,3-dithiolanes and 1,3-di-
thianes generated from different aryl methyl ketones using
different electrophilic reagents are reported. In this study, fa-
cile preparations of monohalo-, -cyano-, -azido-, -thiocy-
ral mechanism is also proposed for the reactions described in
this article.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2005)
Introduction
presence of DMSO has been recently used for deprotection
and ring enlargement of cyclic thioacetals and oxathioacet-
als. Ring expansion chlorination of only one cyclic thioace-
tal has also been reported using this method.[6] In recent
years, we have been involved in exploring some new appli-
cations of molybdenum pentachloride (MoCl5),[7] tungsten
hexachloride (WCl6)[8] and silica chloride (SiO2Cl)[9] in or-
ganic reactions. We have found that molybdenum penta-
chloride (MoCl5),[7] tungsten hexachloride (WCl6)[8] and sil-
ica chloride (SiO2Cl)[9] in the presence of DMSO in dry
dichloromethane can be successfully applied for the one pot
ring-expansion chlorination reactions of 1,3-dithiolanes
and 1,3-dithianes derived from aryl methyl ketones which
bear enolizable hydrogen atoms. Br2 or NBS has also been
used for ring expansion of cyclic thioacetals.[10] 1,4-Dithiins
have also been transformed into derivatives of 5,6-dihydro-
1,4-dithiin by the reaction of BuLi with various
electrophiles.[11Ϫ13] 1,3-Dithiolanes bearing a phenyl or sub-
stituted aromatic group and a methyl (or methylene) group
attached to the C-2 atom of the dithiolane rings undergo
rapid rearrangement to 1,3-dithiolane-dihydro-1,4-dithiin in
the presence of NBS or 1,3-dibromo-5,5-dimethylhydan-
toin (DBH).[14]
It has been reported that some derivatives of 1,4-dithiins
and 1,4-dithiepins show activities as nonpeptide antagonists
of the human Galanin hGAL-1 receptor.[10]
In this article, we report an extensive study of the ring
enlarging monosubstitution reactions of 1,3-dithiolanes and
1,3-dithianes prepared from aryl methyl ketones. These re-
actions were conducted in the presence of N-chloro-, N-
bromo-, N-iodo-, N-cyano-, N-azido- and N-thiocyanatos-
uccinimides in order to prepare monosubstituted (Cl, Br, I,
CN, N3 and SCN) 1,4-dithiins and 1,4-dithiepins in good
The ring-expansion annelation reactions of 1,3-dithiol-
anes (m ϭ 0) and 1,3-dithianes (m ϭ 1), which are five-
and six-membered ring thioacetals, are very useful for the
construction of larger rings bearing sulfur atoms
(Scheme 1).
Scheme 1
A review of the literature reveals that little attention has
been paid to the ring enlargement reactions of 1,3-dithiol-
anes and 1,3-dithianes to their corresponding 1,4-dithiins
(m ϭ 0) and 1,4-dithiepins (m ϭ 1) as shown in Scheme 1.
For this purpose, PhSeCl has been employed for the ring-
expansion reactions in some steroidal compounds.[1] Molec-
ular chlorine in refluxing CH2Cl2/CCl4 has been used for
the conversion of 2,2-dimethyl-1,3-oxathiolane to 2-methyl-
1,4-oxathiin in moderate yield (54%).[2] TeCl4 has also been
applied for the ring enlargements of 1,3-dithiolanes, 1,3-di-
thianes and 1,3-oxathiolanes.[3,4] Br2 or Cl2 in anhydrous
CHCl3 or CCl4 has been used for the synthesis of 2,3-di-
hydro-1,4-dithiins from 1,3-dithilane derivatives of unsym-
metrical ketones[5] and 2,4,6-trichloro-1,3,5-triazine in the
[a]
Department of Chemistry, College of Sciences, Shiraz
University,
Shiraz 71454, Iran
E-mail: firouzabadi@chem.susc.ac.ir
iranpoor@chem.susc.ac.ir
416
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Facile Ring-Expansion Substitution Reactions of 1,3-Dithiolanes and 1,3-Dithianes
FULL PAPER
to excellent yields under neutral and mild reaction con- of three equivalents of NISac and one equivalent of DMSO
ditions (Scheme 2).
in refluxing acetonitrile resulted in the formation of the cor-
responding monoiodo-1,4-dithiin 6c and monoiodo-1,4-di-
thiepin 7c in yields of 60% and 58%, respectively, ac-
companied by the formation of acetophenone in yields of
40 and 42% after 5 h. NBSac and NISac were, therefore,
not suitable reagents for these reactions.
We observed that when 2-methyl-2-(4-nitrophenyl)-1,3-
dithiolane (9) and 2-methyl-2-(4-nitrophenyl)-1,3-dithiane
(10), the phenyl groups of which carry the strong electron-
withdrawing nitro group, were treated with NCS, the de-
sired ring-expanded monochlorinated products 10a and 11a
could be isolated in yields of 89 and 90%, respectively. In
comparison, ring expansion chlorination reactions of simi-
lar substrates by the previously reported methods using the
WCl6/DMSO,[8] MoCl5/DMSO[7] or SiO2Cl/DMSO[9] sys-
tems completely failed and the corresponding 1,4-dithiin
and 1,4-dithiepin compounds were isolated as the sole
products from the reaction mixtures. In order to show the
general applicability of the methods, we studied the reac-
tions of structurally diverse 1,3-dithiolanes and 1,3-di-
thianes with N-halosuccinimides in CH2Cl2 at room tem-
perature. We observed that the reactions proceeded
smoothly and the desired ring-expanded mono-halogeneted
compounds 2aϪ11c were produced in good to high yields.
The results of this study are summarised in Table 1.
In order to show the merit of the methods described, we
compared the experimental results for ring-expansion
chlorination reactions of 1,3-dithiolanes 3, 5, 9 and 1,3-di-
thianes 2, 6, 8, 10 using N-chlorosuccinimide (NCS) with
the previously reported methods using molybdenum penta-
chloride (MoCl5),[7] tungsten hexachloride (WCl6)[8] and sil-
ica chloride (SiO2Cl)[9] in the presence of DMSO in dry
dichloromethane at room temperature (Table 2).
Scheme 2
Results and Discussion
In continuation of our interests in the chemistry of cyclic
thioacetals, we have investigated the reactions of different
N-substituted succinimides with 1,3-dithiolanes and 1,3-di-
thianes derived from aryl methyl ketones at room tempera-
ture. First, we studied the reaction of 2-methyl-2-phenyl-
1,3-dithiolane (5), as a model compound, with N-chlorosuc-
cinimide (NCS) and N-bromosuccinimide (NBS) in dry di-
chloromethane at room temperature. The reactions pro-
ceeded smoothly with an equivalent amount of NCS or
NBS to produce the corresponding 1,4-dithiin 6d in excel-
lent yield as the only isolated product from the reaction
mixture (Scheme 3).
The successful halogenation reactions encouraged us to
study the possibility of using some other N-substituted suc-
cinimides for the ring-enlargement substitution of 1,3-dithi-
olanes and 1,3-dithianes.
However, we first studied the ring-enlargement cyanation
reactions of 1,3-dithiolanes and 1,3-dithianes 1Ϫ10. To this
Scheme 3
We then attempted a similar reaction with two equiva- end, one equivalent of 5, as a model compound, was treated
lents of NCS and NBS under similar reaction conditions. with a mixture of two equivalents of Bu4NCN and NBS in
We found that under such conditions, 6a and 6b were pro- dry CH3CN at room temperature. The reaction proceeded
duced and could be isolated in yields of 87 and 89%, respec- smoothly to completion and 16 was isolated in 88% yield
tively, after 30 min. We also applied similar reaction con- after 30 min. In order to show the role of NBS in this reac-
ditions with N-iodosuccinimide (NIS) for the preparation tion, we studied a similar reaction in the absence of NBS
of 6c from 5 . This reaction also proceeded well and pro- with Bu4NCN. We found that 5 was isolated intact after a
duced the desired product 6c in 89% yield after 30 min.
prolonged reaction time (12 h).
We also studied the ring expansion bromination and iod-
The cyanation reaction was extended to the structurally
ination reactions of 5 and 2-methyl-2-phenyl-1,3-dithiane diverse 1,3-dithiolanes and 1,3-dithianes 1Ϫ10 under simi-
(6) as model compounds using N-bromosaccharin (NBSac) lar reaction conditions. The corresponding 2-cyanato-1,4-
and N-iodosaccharin (NISac)[15] as electrophilic reagents. dithiins 12, 14, 16, 18 and 20 and the 2-cyanato-1,4-dithiep-
When two equivalents of NBSac in refluxing acetonitrile ins 13, 15, 17, 19 and 21 were isolated in high yields. How-
reacted with 5 or 6, the corresponding monobromo-1,4-di- ever, the presence of an electronegative atom such as chlor-
thiin 6b and monobromo-1,4-dithiepin 7b were isolated in ine or a strong electron-withdrawing group such as NO2
yields of 75% and 70% with the production of aceto- on the aromatic ring retarded the reactions effectively. The
phenone as a by-product in yields of 25 and 30%, respec- results of this study are shown in Table 3. All the com-
tively, within 10 to 16 h. Similar substrates in the presence pounds prepared by this protocol showed sharp and strong
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H. Firouzabadi, N. Iranpoor, A. Garzan, H. R. Shaterian, F. Ebrahimzadeh
Table 1. Ring-expansion halogenation of 1,3-dithiolanes and 1,3-dithianes by N-halosuccinimides in dry CH2Cl2 at room temperature
FULL PAPER
[a]
[b]
[c]
1
Reaction time is 30 min. Yields refer to the isolated products. All the compounds are known and gave satisfactory H NMR and
13C NMR spectroscopic data in comparison with authentic samples (see refs.[8,9]).
characteristic IR absorption bands at about 2320 cmϪ1 and purpose, we first studied the reaction of 5, as a model com-
a peak at about 112 ppm in their 13C NMR spectra indicat- pound, in the presence of a mixture of two equivalents of
ing the presence of a CN group in the molecules.
Bu4NN3 and NBS in dry CH3CN at room temperature. The
In this study, we also investigated the ring-expansion az- reaction proceeded well and the desired compound 26 was
idation of 1,3-dithiolanes and 1,3-dithianes 1Ϫ10. For this isolated in a good yield. The protocol was then applied to
418
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Facile Ring-Expansion Substitution Reactions of 1,3-Dithiolanes and 1,3-Dithianes
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Table 2. Comparison of the experimental results obtained for the ring-expansion chlorination of 1,3-dithiolanes and 1,3-dithianes using
N-chlorosuccinimide (NCS) with the previously reported methods using MoCl5,[7] WCl6 and SiO2Cl[9] in CH2Cl2 at room temperature
[8]
the other 1,3-dithiolanes and 1,3-dithianes successfully and sponding 1,3-dithianes. We also observed that the presence
the corresponding azido-substituted 1,4-dithiins 22, 24, 26, of an electronegative atom such as chlorine or an electron-
28 and 30 and 1,4-dithiepins 23, 25, 27, 29 and 31 were withdrawing group such as ϪNO2 retarded the rate of the
isolated in good to excellent yields. The results of this study reactions drastically. As an example, our efforts to prepare
are summarised in Table 4.
2-azido-3-(4-nitrophenyl)dihydro[1,4]dithiepin from its cor-
In general, we noticed that azidation reactions of 1,3- responding 1,3-dithiane 10 in the presence of excess
dithiolanes were much faster than those of their corre- amounts of Bu4NN3 and NBS (3ϫ molar ratio) under re-
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H. Firouzabadi, N. Iranpoor, A. Garzan, H. R. Shaterian, F. Ebrahimzadeh
FULL PAPER
Table 3. Ring-expansion cyanation of 1,3-dithiolanes and 1,3-dithianes by N-cyanosuccinimide in dry CH3CN at room temperature
[a]
Yields refer to isolated products.
flux conditions failed after two days. The workup of the about 9:1. When a similar reaction was carried out at 0 °C,
reaction mixture resulted in the formation of the unsubsti- 36 was obtained as the only product of the reaction. The
tuted ring-expansion product 31 in 51% yield (Table 4).
IR spectrum of the isolated product showed a distinctive
Ring-expansion thiocyanation reactions of 1,3-dithiol- absorption band at 2150 cmϪ1 (sharp) for the SCN group
anes and 1,3-dithianes 1Ϫ10 were also studied. For this in the molecule. In the 13C NMR spectrum of the product,
purpose, 5 was chosen as a model compound and treated the related peak for the SCN group could be observed at
with two equivalents of NH4SCN and NBS in dry CH3CN 113 ppm. In order to show the general application of the
at room temperature. The reaction proceeded smoothly and method, structurally different 1,3-dithiolanes and 1,3-di-
1
was complete within 30 minutes. On the basis of H NMR thianes derived from acetophenones 1Ϫ10 were treated with
spectroscopic analysis, the product was found to be a mix- the two equivalent amounts of NH4SCN and NBS in dry
ture of 36 and its isothiocyanato isomer with a ratio of CH3CN at 0 °C. The desired reactions proceeded well and
420
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Facile Ring-Expansion Substitution Reactions of 1,3-Dithiolanes and 1,3-Dithianes
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Table 4. Ring-expansion azidation of 1,3-dithiolanes and 1,3-dithianes by a Bu4NN3 and NBS mixture in dry CH3CN at room temperature
[a]
Yields refer to the isolated products.
the products were isolated in high yields. The results of this 1,4-dithiepins during the progress of the reaction. As has
study are shown in Table 5.
been established, the formation of six-membered rings (1,4-
Similar to the ring expansion cyanation and azidation re- dithiins) from the straight chain intermediates (Scheme 4,
actions of dithiolanes 1, 3, 5, 7 and 9, thiocyanation reac- III) is easier than the formation of the seven-membered
tions of these compounds with a mixture of Bu4NSCN and rings (1,4-dithiepins) from their corresponding straight
NBS were also faster than those of the corresponding di- chain intermediates. We have also studied several key-step
thianes 2, 4, 6, 8 and 10. The presence of electron-with- reactions in order to propose a general mechanism for the
drawing groups on the aromatic rings in 7, 8, 9 and 10 effec- reactions. First, we treated NBS with NH4SCN or Bu4NCN
tively retarded the reactions. This rate retardation is prob- in CH3CN at room temperature in order to isolate the cor-
ably due to the formation of intermediates with cationic responding substituted succinimides. From the reaction of
character (Scheme 4, II) and also to the generation of the NBS and NH4SCN, immediate precipitation of NH4Br was
straight chain intermediates (Scheme 4, III) which should observed. The precipitate was isolated by filtration. Evapor-
rearrange to cyclic compounds to produce 1,4-dithiins or ation of the solvent resulted in N-thiocyanatosuccinimide
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H. Firouzabadi, N. Iranpoor, A. Garzan, H. R. Shaterian, F. Ebrahimzadeh
FULL PAPER
Table 5. Ring-expansion thiocyanation of 1,3-dithiolanes and 1,3-dithianes by a NH4SCN and NBS mixture in dry CH3CN at 0 °C
[a]
Yields refer to the total yields of the isolated products.
as a white powder. Preparation of N-cyanosuccinimide was went a ring-expansion substitution reaction and produced
performed by the treatment of NBS with Bu4NCN in the desired substituted 1,4-dithiins 14 and 34 in high yields
CHCl3 which, after washing with water, drying and evapor- (Schemes 5 and 6).
ation of the solvent, was isolated as a white powder. As a
These results show that both N-cyanosuccinimide and N-
model reaction, the dithiolane 3 was treated with 2.2 equiv- thiocyanatosuccinimide carrying electrophilic SCN and CN
alents of the isolated N-cyano- or N-thiocyanato-succinim- moieties were able to bring about facile ring expansion sub-
ides, respectively. We observed that the dithiolane 3 under- stitution reactions. In order to eliminate the possibility of
422
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Facile Ring-Expansion Substitution Reactions of 1,3-Dithiolanes and 1,3-Dithianes
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Scheme 4
Scheme 5
Scheme 6
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H. Firouzabadi, N. Iranpoor, A. Garzan, H. R. Shaterian, F. Ebrahimzadeh
FULL PAPER
(2ϫ10 mL). The organic layer was separated and dried with anhy-
drous Na2SO4 and the solvent was evaporated under reduced press-
ure to afford the crude products. Further purification was per-
formed using chromatography over a short column of silica gel
(petroleum ether 60Ϫ80 °C as eluent) which, after evaporation of
the solvent, afforded the desired pure 2b in 99% yield (0.300 g).
direct formation of these products through substitution re-
Ϫ
actions of bromine in the dithiin with SCNϪ, CNϪ and N3
nucleophiles, we studied the reaction of 3-bromo-1,4-dithiin
4b as a model compound with NH4SCN in CH3CN in the
absence of NBS at room temperature. Our findings have
shown that the 3-bromo-1,4-dithiin 4b could be isolated in-
tact after 24 h (Scheme 7).
Typical Procedure for Conversion of 2 to 3c: To a solution of 2-
(4-methoxy-phenyl)-2-methyl-1,3-dithiane (1 mmol, 0.24 g) in dry
CH2Cl2 (20 mL) was added NIS (2 mmol, 0.45 g) in dry CH2Cl2
(20 mL) from a dropping funnel over a period of 5 min while the
resultant solution was stirred at room temperature. After com-
pletion of the addition, the solution was stirred for 30Ϫ45 min and
the reaction was then quenched with an aqueous solution of NaOH
(25 mL, 10%) and extracted with CH2Cl2 (3ϫ25 mL). The organic
extracts were washed successively with brine (15 mL) and water
(2ϫ10 mL). The organic layer was separated and dried with anhy-
drous Na2SO4 and the solvent was evaporated under reduced press-
ure to afford the crude product. Further purification was per-
formed using chromatography over a short column of silica gel
(petroleum ether 60Ϫ80 °C as eluent) which, after evaporation of
the solvent, afforded the desired pure 3c with 80% yield (0.291 g).
Scheme 7
With these facts in mind, we have proposed a general
mechanism which clarifies the probable steps involved in
the reaction presented in this article (Scheme 4).
In this study we have presented a simple and high yield
one pot preparation of substituted (Cl, Br, I, CN, N3, SCN)
1,4-dithiins and 1,4-dithiepines from their corresponding
1,3-dithiolanes and 1,3-dithanes. We have also presented a
mechanism which clarifies the probable steps involved in
the reactions.
Typical Procedure for Conversion of 1 to 12: A solution of NBS
(2.2 mmol, 0.391 g) and tetrabutylammonium cyanide (2.2 mmol,
0.59 g) in dry acetonitrile (10 mL) was stirred at room temperature
for 15 min. 2-(4-Methoxyphenyl)-2-methyl-1,3-dithiolane (1.0
mmol, 0.226 g) was then added to the solution and the resultant
mixture was stirred at room temperature for 5 min. Silica gel was
added to the reaction mixture and the solvent was evaporated on
a rotary evaporator. The resultant powder was applied to a silica
gel column and eluted with hexane/ethyl acetate, 9:1, to afford 12
in 98% yield (0.244 g).
Experimental Section
General: All solvents and reagents were purchased from Fluka or
Merck. The products were purified by column or thick layer chro-
matography techniques. FT-IR spectra were recorded on a Shim-
adzu DR-8001 spectrometer. NMR spectra were recorded on a
Bruker Avance DPX 250 MHz instrument. Mass spectra were re-
corded on a Shimadzu GC-MS-QP 1000PX apparatus. Melting
points are not corrected.
Typical Procedure for Conversion of 7 to 28: A solution of NBS
(2.2 mmol, 0.391 g) and tetrabutylammonium azide (2.2 mmol,
0.624 g) in dry acetonitrile (10 mL) was stirred at room temperature
for 15 min. 2-(4-Chlorophenyl)-2-methyl-1,3-dithiolane (1.0 mmol,
0.23 g) was added to the solution and the resultant mixture was
stirred at room temperature for 14 h. To the resultant mixture,
was added silica gel and the solvent was evaporated on a rotary
evaporator. The resultant powder was applied to a silica gel column
and eluted with hexane/ethyl acetate, 9:1, to afford 28 in 93%
yield (0.250 g).
Typical Procedure for Conversion of 2 to 3a: To a solution of 2-
(4-methoxy-phenyl)-2-methyl-1,3-dithiane (1 mmol, 0.24 g) in dry
CH2Cl2 (20 mL) was added NCS (2 mmol, 0.267 g) in dry CH2Cl2
(20 mL) from a dropping funnel over a period of 5 min while the
resultant solution was stirred at room temperature. After com-
pletion of the addition, the solution was stirred for 30Ϫ45 min and
the reaction was then quenched with an aqueous solution of NaOH
(10% 25 mL) and extracted with CH2Cl2 (3ϫ25 mL). The organic
extracts were washed successively with brine (15 mL) and water
(2ϫ10 mL). The organic layer was separated and dried with anhy-
drous Na2SO4 and the solvent was evaporated under reduced press-
ure to afford the crude product. Further purification was per-
formed by chromatography over a short column of silica gel (petro-
leum ether 60Ϫ80 °C as eluent) which, after evaporation of the
solvent, afforded the desired pure 3a in 79% yield (0.215 g).
Typical Procedure for Conversion of 5 to 36: A solution of NBS
(2.2 mmol, 0.391 g) and ammonium thiocyanate (2.2 mmol,
0.167 g) in dry CH3CN (10 mL) was stirred at 0 °C for 15 min. 5
(1.0 mmol, 0.196 g) was added to the solution and the resultant
mixture was stirred at room temperature for 30 min. To the result-
ant mixture was added silica gel and the solvent was evaporated on
a rotary evaporator. The resultant solid mass was applied to a silica
gel column and eluted with hexane/EtOAc, 9:1, to afford 36 in 79%
yield (0.198 g).
Preparation of Tetrabutylammonium Azide: To a solution of tetra-
butylammonium bromide (2.2 mmol, 0.709 g) in distilled water
(10 mL) was added sodium azide (2.2 mmol, 0.143 g). The mixture
was stirred for 30 min. The resultant mixture was extracted with
CH2Cl2 (4ϫ10 mL). The organic layer was separated and dried
with anhydrous CaCl2. The solvent was evaporated under reduced
pressure to afford tetrabutylammonium azide as a white powder in
90% yield (0.256 g).
Typical Procedure for Conversion of 1 to 2b: To a solution of 2-(4-
methoxy-phenyl)-2-methyl-1,3-dithiolane (1 mmol, 0.226 g) in dry
CH2Cl2 (20 mL) was added NBS (2 mmol, 0.356 g) in dry CH2Cl2
(20 mL) from a dropping funnel over a period of 5 min while the
resultant solution was stirred at room temperature. After com-
pletion of the addition, the solution was stirred for 30Ϫ45 min and
the reaction was then quenched with an aqueous solution of NaOH
(25 mL, 10%) and extracted with CH2Cl2 (3ϫ25 mL). The organic
2a: Yellow viscous liquid; 88% yield (0.227 g). 1H NMR (250 MHz,
extracts were washed successively with brine (15 mL) and water CDCl3): δ ϭ 3.19Ϫ3.33 (m, 4 H, CH2CH2), 3.68(s, 3 H, OCH3),
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FULL PAPER
6.77 (d, J ϭ 8.8 Hz, 2 H, Ar), 7.23 (d, J ϭ 8.8 Hz, 2 H, Ar) ppm. 5c: Yellow viscous liquid; 82% yield (0.336 g). 1H NMR (250 MHz,
13C NMR (63 MHz, CDCl3): δ ϭ 30.8, 32.6, 55.7, 113.2, 114.2, CDCl3): δ ϭ 2.21Ϫ2.25 (m, 2 H, CH2CH2CH2), 3.57Ϫ3.66 (m, 4
126.5, 130.4, 133.1, 163.9 ppm. [M]ϩ calcd for C11H11ClOS2: 258,
found 258. C11H11ClOS2 (258.8): calcd. C 51.1, H 4.2; found C
51.2, H 4.2.
H, CH2CH2CH2), 7.25Ϫ7.60 (m, 9 H, biphenyl) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 30.5, 31.0, 32.6, 69.6, 125.0, 126.9, 127.0,
127.4, 127.5, 127.7, 128.2, 128.8, 143.9 ppm. [M]ϩ calcd. for
C17H15IS2: 410, found 410. C17H15IS2 (410.3): calcd. C 49.8, H 3.7;
found C 49.8, H 3.9.
2b: Yellow viscous liquid; 99% yield (0.303 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.28Ϫ3.35 (m, 4 H, CH2CH2), 3.74(s, 3 H, OCH3),
6.79 (d, J ϭ 8.7 Hz, 2 H, Ar), 7.28 (d, J ϭ 8.7 Hz, 2 H, Ar) ppm.
13C NMR (63 MHz, CDCl3): δ ϭ 31.0, 33.2, 55.6, 113.9, 114.2,
126.5, 131.2, 133.9, 161.6 ppm. [M]ϩ calcd for C11H11BrOS2: 302,
found 302. C11H11BrOS2 (303.2): calcd. C 43.6, H 3.6; found C
43.8, H 3.7.
6b: Yellow viscous liquid; 89% yield (0.243 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.21 (m, 4 H, CH2CH2), 7.40 (m, 5 H, Ph) ppm. 13C
NMR (63 MHz, CDCl3): δ ϭ 30.2, 32.6, 111.9, 125.0, 128.4, 130.2,
147.7, 148.7 ppm. [M]ϩ calcd. for C10H9BrS2: 272, found 272.
C10H9BrS2 (273.2): calcd. C 44.0, H 3.3; found C 44.2, H 3.3.
2c: Yellow viscous liquid; 70% yield (0.245 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.10Ϫ3.25 (m, 4 H, CH2CH2), 3.69(s, 3 H, OCH3),
6.70 (d, J ϭ 8.1 Hz, 2 H, Ar), 7.20 (d, J ϭ 8.1 Hz, 2 H, Ar) ppm.
13C NMR (63 MHz, CDCl3): δ ϭ 27.1, 29.1, 55.7, 69.5, 113.0,
114.1, 126.5, 130.7, 163.9 ppm. [M]ϩ calcd for C11H11IOS2: 350,
found 350. C11H11IOS2 (350.2): calcd. C 37.7, H 3.1; found C 37.7,
H 3.2.
6c: Yellow viscous liquid; 89% yield (0.284 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.04Ϫ3.18 (m, 4 H, CH2CH2), 7.19Ϫ7.23 (m, 5 H,
Ph) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 27.2, 28.3, 69.5, 126.3,
128.4, 128.7, 129.4, 140.7 ppm. [M]ϩ calcd. for C10H9IS2: 320,
found 320. C10H9IS2 (320.2): calcd. C 37.5, H 2.8; found C 37.5,
H 2.9.
7b: Yellow viscous liquid; 90% yield (0.258 g). 1H NMR (250 MHz,
3b: Yellow viscous liquid; 98% yield (0.311 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.45Ϫ2.46 (m, 2 H, CH2CH2CH2), 3.78Ϫ3.79 (m, 4
H, CH2CH2CH2), 3.73 (s, 3 H, OCH3), 6.70 (d, J ϭ 8.7 Hz, 2 H,
Ar), 7.79 (d, J ϭ 8.7 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz,
CDCl3): δ ϭ 24.4, 27.9, 29.4, 53.9, 111.5, 112.3, 126.5, 129.2, 131.6,
162.2 ppm. [M]ϩ calcd for C12H13BrOS2: 316, found 316.
C12H13BrOS2 (317.3): calcd. C 45.4, H 4.1; found C 45.5, H 4.2.
CDCl3):
δ ϭ 2.29 (m, 2 H, CH2CH2CH2), 3.5 (m, 4 H,
CH2CH2CH2), 7.5Ϫ8.2 (m, 5 H, Ph) ppm. 13C NMR (63 MHz,
CDCl3): δ ϭ 29.2, 31.5, 33.3, 110.0, 124.3, 130.6, 131.1, 147.6,
148.5 ppm. [M]ϩ calcd. for C11H11BrS2: 286, found 286.
C11H11BrS2 (287.2): calcd. C 46.0, H 3.8; found C 46.2, H 3.7.
7c: Yellow viscous liquid; 79% yield (0.264 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 1.99Ϫ2.04 (m, 2 H, CH2CH2CH2), 3.00Ϫ3.06 (m, 4
H, CH2CH2CH2), 7.34Ϫ7.88 (m, 5 H, Ph) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 28.9, 31.5, 33.9, 69.5, 127.7, 130.0, 131.2,
133.5, 137.5 ppm. [M]ϩ calcd. for C11H11IS2: 334, found 334.
C11H11IS2 (334.2): calcd. C 39.5, H 3.3; found C 39.5, H 3.4.
3c: White viscous liquid; 80% yield (0.291 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.16Ϫ2.23 (m, 2 H, CH2CH2CH2), 3.52Ϫ3.61 (m, 4
H, CH2CH2CH2), 3.80 (s, 3 H, OCH3), 6.82 (d, J ϭ 8.5 Hz, 2 H,
Ar), 7.41 [(d, J ϭ 8.5 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz,
CDCl3): δ ϭ 25.9, 28.6, 32.0, 55.1, 69.5, 113.1, 123.3, 129.9, 130.2,
163.1 ppm. [M]ϩ calcd for C12H13IOS2: 364, found 364.
C12H13IOS2 (364.3): calcd. C 39.6, H 3.6; found C 39.6, H 3.7.
8a: Yellow viscous liquid; 89% yield (0.234 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.24Ϫ3.27 (m, 4 H, CH2CH2), 7.18 (d, J ϭ 8.5 Hz, 2
H, Ar), 7.39 (d, J ϭ 8.5 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz,
4b: Yellow solid; 87% yield (0.304 g); m.p. 94 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 3.24 (m, 4 H, CH2CH2), 7.23Ϫ7.54 (m, 9
H, biphenyl) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 30.2, 32.6,
112.9, 127.7, 128.4, 129.1, 129.5, 130.0, 130.6, 131.3, 131.9,
146.6 ppm. [M]ϩ calcd for C16H13BrS2: 348, found 348. C16H13BrS2
(349.3): calcd. C 55.0, H 3.7; found C 55.0, H 3.7.
CDCl3):
δ ϭ 30.4, 32.6, 113.6, 125.4, 128.7, 131.4, 134.7,
136.7 ppm. [M]ϩ calcd. for C10H8Cl2S2: 262, found 262.
C10H8Cl2S2 (263.2): calcd. C 45.7, H 3.0; found C 45.7, H 3.3.
8b: Yellow viscous liquid; 92% yield (0.282 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.25Ϫ3.36 (m, 4 H, CH2CH2), 7.18 (d, J ϭ 8.4 Hz, 2
H, Ar), 7.30 (d, J ϭ 8.4 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz,
4c: Yellow solid; 78% yield (0.309 g); m.p. 105 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 3.26Ϫ3.32 (m, 4 H, CH2CH2), 7.36Ϫ8.08
(m, 9 H, biphenyl) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 27.3,
28.3, 69.6, 126.6, 127.4, 127.6, 127.8, 128.6, 128.8, 129.4, 129.8,
143.6 ppm. [M]ϩ calcd for C16H13IS2: 396, found 396. C16H13IS2
(396.3): calcd. C 48.5, H 3.3; found C 48.5, H 3.2.
CDCl3):
δ ϭ 30.9, 33.3, 113.7, 126.4, 128.9, 131.4, 134.7,
138.6 ppm. [M]ϩ calcd. for C10H8BrClS2: 306, found 306.
C10H8BrClS2 (307.7): calcd. C 39.1, H 2.6; found C 39.3, H 2.7.
8c: Yellow viscous liquid; 71% yield (0.251 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.13Ϫ3.20 (m, 4 H, CH2CH2), 7.12 [(d, J ϭ 8.6 Hz,
2 H, Ar),7.28 (d, J ϭ 8.6 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz,
CDCl3): δ ϭ 27.2, 28.1, 69.1, 127.1, 127.5, 128.9, 133.8, 139.1 ppm.
[M]ϩ calcd. for C10H8ClIS2: 354, found 354. C10H8ClIS2 (354.7):
calcd. C 33.9, H 2.3; found C 33.7, H 2.4.
5a: Yellow viscous liquid; 72% yield (0.229 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.44 (m, 2 H, CH2CH2CH2), 3.28 (m, 4 H,
CH2CH2CH2), 7.17Ϫ7.87 (m, 9 H, biphenyl) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 27.2, 28.8, 29.7, 113.0, 127.3, 127.6, 127.9,
128.3, 128.7, 129.3, 129.5, 130.6, 143.2 ppm. [M]ϩ calcd for
C17H15ClS2: 318, found 318. C17H15ClS2 (318.9): calcd. C 64.0, H
4.7; found C 64.0, H 4.9.
9b: Yellow viscous liquid; 90% yield (0.289 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.09Ϫ2.39 (m, 2 H, CH2CH2CH2), 3.28Ϫ3.48 (m, 4
H, CH2CH2CH2), 7.29 (d, J ϭ 8.5 Hz, 2 H, Ar), 7.38 (d, J ϭ
8.5 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 29.8, 33.4,
33.6, 113.8, 126.2, 129.5, 132.1, 134.8, 138.8 ppm. [M]ϩ calcd. for
C11H10BrClS2: 320, found 320. C11H10BrClS2 (321.7): calcd. C
41.1, H 3.1; found C 41.2, H 3.2.
5b: Yellow viscous liquid; 70% yield (0.253 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.04Ϫ2.13 (m, 2 H, CH2CH2CH2), 2.79Ϫ2.81 (m, 4
H, CH2CH2CH2), 7.41Ϫ8.08 (m, 9 H, biphenyl) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 26.7, 28.3, 30.8, 113.05, 127.2, 127.5, 128.4,
128.9, 129.0, 129.4, 129.6, 131.4, 146.6 ppm. [M]ϩ calcd for 9c: White viscous liquid; 78% yield (0.287 g). H NMR (250 MHz,
C17H15BrS2: 362, found 362. C17H15BrS2 (363.3): calcd. C 56.2, H CDCl3): δ ϭ 2.16Ϫ2.26 (m, 2 H, CH2CH2CH2), 3.55Ϫ3.64 (m, 4
1
4.1; found C 56.3, H 4.2.
H, CH2CH2CH2), 7.24 (d, J ϭ 7.9 Hz, 2 H, Ar), 7.55 (d, J ϭ
Eur. J. Org. Chem. 2005, 416Ϫ428
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© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
425

H. Firouzabadi, N. Iranpoor, A. Garzan, H. R. Shaterian, F. Ebrahimzadeh
FULL PAPER
7.9 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 30.3, 30.9,
14: Yellow viscous liquid; 82% yield (0.242 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.32Ϫ3.37 (m, 4 H, CH2CH2), 7.18Ϫ7.53 (m, 9 H,
32.6, 69.1, 129.2, 129.9, 130.6, 135.8, 139.9 ppm. [M]ϩ calcd. for
C11H10ClIS2: 368, found 368. C11H10ClIS2 (368.7): calcd. C 35.9, biphenyl) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 30.8, 33.3, 111.2,
H 2.7; found C 35.8, H 2.6.
112.9, 127.3, 127.5, 127.9, 128.3, 128.9, 129.2, 130.4, 130.6,
151.1 ppm. [M]ϩ calcd. for C17H13NS2: 295, found 295. C17H13NS2
(295.4): calcd. C 69.2, H 4.4; found C 68.9, H 4.5.
10a: Yellow solid; 89% yield (0.243 g); m.p. 92 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 3.24 (m, 4 H, CH2CH2), 7.49 (d, J ϭ
8.7 Hz, 2 H, Ar), 7.89 [(d, J ϭ 8.7 Hz, 2 H, Ar) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 30.3, 33.1, 115.2, 125.5, 127.5, 130.1, 141.6,
148.5 ppm. [M]ϩ calcd. for C10H8ClNO2S2: 273, found 273.
15: Yellow viscous liquid; 85% yield (0.263 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.45Ϫ2.49 (m, 2 H, CH2CH2CH2), 3.42Ϫ3.47 (m, 4
H, CH2CH2CH2), 7.29Ϫ8.00 (m, 9 H, biphenyl) ppm. 13C NMR
C10H8ClNO2S2 (273.8): calcd. C 43.9, H 2.9; found C 44.0, H 3.0. (63 MHz, CDCl3): δ ϭ 27.2, 28.8, 31.2, 111.2, 113.0, 127.1, 127.7,
127.9, 128.2, 128.9, 129.3, 129.4, 129.7, 150.9 ppm. [M]ϩ calcd. for
C18H15NS2: 309, found 309. C18H15NS2 (309.4): calcd. C 69.9, H
4.9; found C 69.7, H 5.1.
10b: Yellow solid; 92% yield (0.293 g); m.p. 98 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 3.23 (m, 4 H, CH2CH2), 7.48 (d, J ϭ
8.8 Hz, 2 H, Ar), 7.77 (d, J ϭ 8.8 Hz, 2 H, Ar) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 30.6, 33.1, 115.9, 125.3, 127.2, 130.9, 141.6,
16: Yellow viscous liquid; 88% yield (0.193 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.19Ϫ3.29 (m, 4 H, CH2CH2), 7.27 (m, 5 H, Ph) ppm.
148.5 ppm. [M]ϩ calcd. for C10H8BrNO2S2: 317, found 317.
C10H8BrNO2S2 (318.2): calcd. C 37.7, H 2.5; found C 37.9, H 2.8. 13C NMR (63 MHz, CDCl3): δ ϭ 30.1, 33.2, 100.4, 112.3, 126.3,
128.2, 128.8, 129.9, 150.2 ppm. [M]ϩ calcd. for C11H9NS2: 219,
10c: Orange solid; 86% yield (0.314 g); m.p. 110 °C. 1H NMR
found 219. C11H9NS2 (219.3): calcd. C 60.3, H 4.1; found C 60.1,
H 4.2.
(250 MHz, CDCl3): δ ϭ 3.21 (m, 4 H, CH2CH2), 7.46 (d, J ϭ
7.6 Hz, 2 H, Ar), 8.0 (d, J ϭ 7.6 Hz, 2 H, Ar) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 25.1, 25.3, 115.8, 69.5, 123.7, 127.4, 139.5,
144.2 ppm. [M]ϩ calcd. for C10H8INO2S2: 365, found 365.
C10H8INO2S2 (365.2): calcd. C 32.9, H 2.2; found C 33.0, H 2.3.
17: Yellow viscous liquid; 88% yield (0.205 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.08Ϫ2.17 (m, 2 H, CH2CH2CH2), 3.44Ϫ3.49 (m, 4
H, CH2CH2CH2), 7.27 (m, 5 H, Ph) ppm. 13C NMR (63 MHz,
CDCl3): δ ϭ 30.1, 32.6, 34.9, 111.2, 112.2, 128.6, 129.1, 129.3,
129.9, 150.9 ppm. [M]ϩ calcd. for C12H11NS2: 233, found 233.
C12H11NS2 (233.3): calcd. C 61.8, H 4.7; found C 61.6, H 4.6.
11a: Yellow solid; 90% yield (0.258 g); m.p. 93 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 2.05Ϫ2.40 (m, 2 H, CH2CH2CH2),
3.41Ϫ3.50 (m,4 H, CH2CH2CH2), 7.22 (d, J ϭ 8.5 Hz, 2 H, Ar),
7.45 (d, J ϭ 8.5 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3): 18: White viscous liquid; 98% yield (0.248 g). H NMR (250 MHz,
1
δ ϭ 29.9, 31.7, 33.8, 120.1, 125.4, 128.2, 130.9, 141.5, 148.5 ppm.
[M]ϩ calcd. for C11H10ClNO2S2: 287, found 287. C11H10ClNO2S2
(287.8): calcd. C 45.9, H 3.5; found C 46.0, H 3.7.
CDCl3): δ ϭ 3.27Ϫ3.35 (m, 4 H, CH2CH2), 7.20 [(d, J ϭ 8.4 Hz,
2 H, Ar (AAЈXXЈ system)], 7.28 (d, J ϭ 8.4 Hz, 2 H, Ar) ppm. 13
C
NMR (63 MHz, CDCl3): δ ϭ 29.0, 31.6, 99.6, 112.3, 125.9, 127.3,
129.7, 133.1, 151.1 ppm. [M]ϩ calcd. for C11H8ClNS2: 253, found
253. C11H8ClNS2 (253.8): calcd. C 52.1, H 3.2; found C 52.1, H 3.4.
11b: Yellow solid; 97% yield (0.322 g); m.p. 88 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 1.99Ϫ2.23 (m, 2 H, CH2CH2CH2),
3.41Ϫ3.50 (m,4 H, CH2CH2CH2), 7.43 (d, J ϭ 8.2 Hz, 2 H, Ar), 19: Yellow viscous liquid; 74% yield (0.198 g). 1H NMR (250 MHz,
7.74 (d, J ϭ 8.2 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3): CDCl3): δ ϭ 1.97Ϫ2.04 (m, 2 H, CH2CH2CH2), 3.24Ϫ3.34 (m, 4
δ ϭ 29.8, 31.4, 33.6, 115.8, 125.3, 126.9, 130.8, 141.4, 148.5 ppm.
[M]ϩ calcd. for C11H10BrNO2S2: 331, found 331. C11H10BrNO2S2
(332.2): calcd. C 39.8, H 3.0; found C 40.2, H 3.1.
H, CH2CH2CH2), 7.35 (d, J ϭ 7.3 Hz, 2 H, Ar), 7.69 (d, J ϭ
7.3 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 24.0,
25.6, 28.7, 111.2, 112.2, 127.6, 128.2, 129.1, 135.2, 150.9 ppm. [M]ϩ
calcd. for C12H10ClNS2: 267, found 267. C12H10ClNS2 (267.8):
calcd. C 53.9, H 3.7; found C 53.7, H 3.9.
11c: Orange solid; 87% yield (0.330 g); m.p. 108 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 2.00 (m, 2 H, CH2CH2CH2), 2.67 (m, 4
H, CH2CH2CH2), 8.08 (d, J ϭ 7.3 Hz, 2 H, Ar), 8.30 (d, J ϭ 20: Yellow solid; 97% yield (0.256 g); m.p. 80 °C. 1H NMR
7.3 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 24.4, 25.7,
28.9, 69.5, 125.8, 127.5, 128.0, 139.5, 148.5 ppm. [M]ϩ calcd. for
C11H10INO2S2: 379, found 379. C11H10INO2S2 (379.2): calcd. C
34.8, H 2.6; found C 34.9, H 2.7.
(250 MHz, CDCl3): δ ϭ 3.23Ϫ3.39 (m, 4 H, CH2CH2), 7.45 (d,
J ϭ 7.5 Hz, 2 H, Ar), 8.16 (d, J ϭ 7.5 Hz, 2 H, Ar) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 27.6, 30.1, 111.1, 117.9, 123.9, 124.3, 126.5,
144.8, 151.1 ppm. [M]ϩ calcd. for C11H8N2O2S2: 264, found 264.
C11H8N2O2S2 (264.3): calcd. C 50.0, H 3.0; found C 49.8, H 2.9.
12: Yellow viscous liquid; 98% yield (0.244 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.25Ϫ3.38 (m, 4 H, CH2CH2), 3.73(s, 3 H, OCH3),
21: Yellow solid; 70% yield (0.195 g); m.p. 82 °C. 1H NMR
6.79 (d, J ϭ 8.7 Hz, 2 H, Ar), 7.22 (d, J ϭ 8.7 Hz, 2 H, Ar) ppm. (250 MHz, CDCl3): δ ϭ 2.15Ϫ2.20 (m, 2 H, CH2CH2CH2),
13C NMR (63 MHz, CDCl3): δ ϭ 31.1, 33.2, 55.7, 100.0, 113.2, 3.58Ϫ3.62 (m, 4 H, CH2CH2CH2), 7.42 (d, J ϭ 7.3 Hz, 2 H, Ar),
114.0, 127.5, 131.2, 159.9, 163.9 ppm. [M]ϩ calcd. for C12H11NOS2:
249, found 249. C12H11NOS2 (249.3): calcd. C 57.8, H 4.5; found
C 58.0, H 4.7.
8.08 (d, J ϭ 7.3 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3):
δ ϭ 26.6, 31.1, 33.3, 111.2, 112.2, 123.9, 127.5, 128.1, 145.1, 150.9
ppm. [M]ϩ calcd. for C12H10N2O2S2: 278, found 278.
C12H10N2O2S2 (278.3): calcd. C 51.8, H 3.6; found C 51.8, H 3.4.
13: Dark green viscous liquid; 73% yield (0.192 g). 1H NMR
(250 MHz, CDCl3): δ ϭ 1.97Ϫ2.06 (m, 2 H, CH2CH2CH2), 22: White viscous liquid; 84% yield (0.223 g). H NMR (250 MHz,
1
2.60Ϫ3.26 (m, 4 H, CH2CH2CH2), 3.80 (s, 3 H, OCH3), 6.85 (d,
CDCl3): δ ϭ 3.25Ϫ3.38 (m, 4 H, CH2CH2), 3.73(s, 3 H, OCH3),
J ϭ 8.4 Hz, 2 H, Ar),7.89 (d, J ϭ 8.4 Hz, 2 H, Ar) ppm. 13C NMR 6.76 (d, J ϭ 8.7 Hz, 2 H, Ar), 7.13 (d, J ϭ 8.7 Hz, 2 H, Ar) ppm.
(63 MHz, CDCl3): δ ϭ 25.2, 26.8, 28.5, 55.5, 113.6, 113.8, 113.8,
13C NMR (63 MHz, CDCl3): δ ϭ 31.1, 33.2, 55.7, 114.0, 114.2,
130.5, 131.3, 159.9, 162.8 ppm. [M]ϩ calcd. for C13H13NOS2: 263,
127.5, 131.2, 141.2, 159.9 ppm. [M]ϩ calcd. for C11H11N3OS2: 265,
found 263. C13H13NOS2 (263.4): calcd. C 59.3, H 4.9; found C found 265. C11H11N3OS2 (265.3): calcd. C 49.8, H 4.1; found C
59.1, H 4.8. 49.8, H 4.2.
426
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Eur. J. Org. Chem. 2005, 416Ϫ428

Facile Ring-Expansion Substitution Reactions of 1,3-Dithiolanes and 1,3-Dithianes
23: Dark green viscous liquid; 86% yield (0.240 g). 1H NMR 132.8, 147.9 ppm. [M]ϩ calcd. for C11H11NO2S2: 253, found 253.
FULL PAPER
(250 MHz, CDCl3): δ ϭ 2.02Ϫ2.04 (m, 2 H, CH2CH2CH2), C11H11NO2S2 (253.3): calcd. C 52.1, H 4.4; found C 52.1, H 4.4.
3.23Ϫ3.33 (m, 4 H, CH2CH2CH2), 3.78(s, 3 H, OCH3), 6.82 (d,
32: Yellow viscous liquid; 91% yield (0.256 g). 1H NMR (250 MHz,
J ϭ 8.0 Hz, 2 H, Ar), 7.86 (d, J ϭ 8.0 Hz, 2 H, Ar) ppm. 13C NMR
CDCl3): δ ϭ 3.11Ϫ3.24 (m, 4 H, CH2CH2), 3.72 (s, 3 H, OCH3),
(63 MHz, CDCl3): δ ϭ 25.6, 27.2, 31.0, 55.8, 114.4, 128.2, 130.9,
6.74 (d, J ϭ 8.7 Hz, 2 H, Ar), 7.36 (d, J ϭ 8.7 Hz, 2 H, Ar) ppm.
131.3, 141.3, 164.1 ppm. [M]ϩ calcd. for C12H13N3OS2: 279, found
279. C12H13N3OS2 (279.4): calcd. C 51.6, H 4.7; found C 51.5, H
13C NMR (63 MHz, CDCl3): δ ϭ 26.0, 27.5, 54.6, 110.2, 112.5,
113.1, 126.5, 127.4, 127.5, 158.7 ppm. [M]ϩ calcd. for C12H11NOS3:
4.8.
281, found 281. C12H11NOS3 (281.4): calcd. C 51.2, H 3.9; found
24: Yellow solid; 70% yield (0.218 g); m.p. 62 °C. 1H NMR
C 51.2, H 4.1.
(250 MHz, CDCl3): δ ϭ 3.18Ϫ3.42 (m, 4 H, CH2CH2), 7.37Ϫ7.55
33: Yellow viscous liquid; 88% yield (0.259 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.09Ϫ2.14 (m, 2 H, CH2CH2CH2), 2.48 (m, 4 H,
(m, 9 H, biphenyl) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 30.8,
33.3, 113.0, 126.6, 127.3, 127.5, 127.8, 127.9, 128.5, 129.1, 130.8,
CH2CH2CH2), 3.79(s, 3 H, OCH3), 6.80 (d, J ϭ 8.8 Hz, 2 H, Ar),
141.2 ppm. [M]ϩ calcd. for C16H13N3S2: 311, found 311.
7.87 (d, J ϭ 8.8 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3):
C16H13N3S2 (311.4): calcd. C 61.7, H 4.2; found C 61.6, H 4.4.
δ ϭ 28.9, 32.7, 34.3, 54.4, 112.6, 112.9, 129.3, 129.6, 130.1, 136.9,
162.4 ppm. [M]ϩ calcd. for C13H13NOS3: 295, found 295.
C13H13NOS3 (295.4): calcd. C 52.9, H 4.4; found C 52.8, H 4.6.
25: Yellow solid; 90% yield (0.292 g); m.p. 60 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 2.02Ϫ2.07 (m, 2 H, CH2CH2CH2),
3.25Ϫ3.36 (m, 4 H, CH2CH2CH2), 7.27Ϫ7.97 (m, 9 H, biphenyl)
ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 25.6, 27.1, 31.3, 118.2,
127.6, 127.7, 127.9, 128.6, 128.9, 129.3, 129.7, 130.0, 140.2 ppm.
[M]ϩ calcd. for C17H15N3S2: 325, found 325. C17H15N3S2 (325.4):
calcd. C 62.8, H 4.7; found C 62.7, H 4.5.
34: Yellow solid; 92% yield (0.301 g); m.p. 75 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 3.39Ϫ3.44 (m, 4 H, CH2CH2), 7.19Ϫ7.55
(m, 9 H, biphenyl) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 27.7,
28.8, 112.7, 125.7, 127.0, 127.4, 128.2, 128.5, 128.9, 129.2, 130.1,
130.8, 132.4 ppm. [M]ϩ calcd. for C17H13NS3: 327, found 327.
C17H13NS3 (327.5): calcd. C 62.4, H 4.0; found C 62.3, H 4.2.
26: Yellow viscous liquid; 70% yield (0.164 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.13Ϫ3.23 (m, 4 H, CH2CH2), 7.15Ϫ7.27 (m, 5 H,
Ph) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 30.8, 33.2, 112.9, 126.3,
128.9, 129.3, 129.9, 140.7 ppm. [M]ϩ calcd. for C10H9N3S2: 235,
found 235. C10H9N3S2 (235.3): calcd. C 51.1, H 3.8; found C 51.1,
H 4.0.
35: Yellow viscous liquid; 87% yield (0.297 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.09Ϫ2.19 (m, 2 H, CH2CH2CH2), 3.48Ϫ3.57 (m, 4
H, CH2CH2CH2), 7.29Ϫ7.59 (m, 9 H, biphenyl) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 30.9, 31.4, 32.9, 110.7, 118.6, 126.1, 127.3,
127.8, 128.0, 128.2, 128.6, 129.1, 129.5, 131.5 ppm. [M]ϩ calcd. for
C18H15NS3: 341, found 341. C18H15NS3 (341.5): calcd. C 63.3, H
4.4; found C 63.2, H 4.3.
27: Yellow viscous liquid; 80% yield (0.199 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.10 (m, 2 H, CH2CH2CH2), 3.28Ϫ3.46 (m, 4 H,
CH2CH2CH2), 7.19Ϫ7.43 (m, 5 H, Ph) ppm. 13C NMR (63 MHz,
CDCl3): δ ϭ 25.5, 27.0, 30.8, 120.6, 127.5, 129.7, 130.1, 131.6, 141.0
ppm. [M]ϩ calcd. for C11H11N3S2: 249, found 249. C11H11N3S2
(249.3): calcd. C 53.0, H 4.4; found C 53.1, H 4.6.
36: Yellow viscous liquid; 95% yield (0.238 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.12Ϫ3.35 (m, 4 H, CH2CH2), 7.20Ϫ7.37 (m, 5 H,
Ph) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 27.2, 28.3, 113.0, 125.8,
126.3, 128.2, 128.9, 129.9, 140.7 ppm. [M]ϩ calcd. for C11H9NS3:
251, found 251. C11H9NS3 (251.4): calcd. C 52.6, H 3.6; found C
52.7, H 3.8.
28: Yellow viscous liquid; 93% yield (0.250 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.12Ϫ3.21 (m, 4 H, CH2CH2), 7.17 (d, J ϭ 8.6 Hz, 2
H, Ar), 7.29 (d, J ϭ 8.6 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz,
CDCl3): δ ϭ 30.7, 33.2, 113.7, 127.5, 128.9, 129.0, 131.4, 139.2
ppm. [M]ϩ calcd. for C10H8ClN3S2: 269, found 269. C10H8ClN3S2
(269.8): calcd. C 44.6, H 3.0; found C 44.5, H 3.3.
1
37: White viscous liquid; 93% yield (0.246 g). H NMR (250 MHz,
CDCl3): δ ϭ 2.07Ϫ2.19 (m, 2 H, CH2CH2CH2), 3.43Ϫ3.57 (m, 4
H, CH2CH2CH2), 7.19Ϫ7.39 (m, 5 H, Ph) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 29.4, 33.1, 34.9, 104.8, 125.8, 127.7, 128.7,
129.4, 129.8, 130.1 ppm. [M]ϩ calcd. for C12H11NS3: 265, found
265. C12H11NS3 (265.4): calcd. C 54.3, H 4.2; found C 54.2, H 4.6.
29: Yellow viscous liquid; 79% yield (0.224 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.07 (m, 2 H, CH2CH2CH2), 3.23Ϫ3.33 (m, 4 H,
CH2CH2CH2), 7.35 (d, J ϭ 7.5 Hz, 2 H, Ar), 7.85 (d, J ϭ 7.5 Hz,
2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 25.4, 26.9, 30.1,
118.2, 129.3, 129.6, 130.1, 130.5, 141.0 ppm. [M]ϩ calcd. for
C11H10ClN3S2: 283, found 283. C11H10ClN3S2 (283.8): calcd. C
46.6, H 3.5; found C 46.4, H 3.7.
38: Yellow viscous liquid; 90% yield (0.256 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 3.14Ϫ3.23 (m, 4 H, CH2CH2), 7.12 (d, J ϭ 8.7 Hz, 2
H, Ar), 7.27 (d, J ϭ 8.7 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz,
CDCl3): δ ϭ 27.2, 28.1, 113.6, 127.2, 128.4, 128.9, 129.4, 133.8,
139.2 ppm. [M]ϩ calcd. for C11H8ClNS3: 285, found 285.
C11H8ClNS3 (285.8): calcd. C 46.3, H 2.8; found C 46.2, H 3.2.
30: Orange solid; 77% yield (0.216 g); m.p. 78 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 3.23 (m, 4 H, CH2CH2), 7.45 [(d, J ϭ
8.6 Hz, 2 H, Ar (AAЈXXЈ system), 7.87 (d, J ϭ 8.6 Hz, 2 H, Ar)
ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 26.1, 28.7, 116.5, 122.8,
125.1, 126.9, 141.2, 144.8 ppm. [M]ϩ calcd. for C10H8 N4O2S2: 280,
found 280. C10H8N4O2S2 (280.3): calcd. C 42.9, H 2.9; found C
43.0, H 3.1.
39: Yellow viscous liquid; 93% yield (0.278 g). 1H NMR (250 MHz,
CDCl3): δ ϭ 2.08Ϫ2.16 (m, 2 H, CH2CH2CH2), 3.48Ϫ3.57 (m, 4
H, CH2CH2CH2), 7.16 (d, J ϭ 8.7 Hz, 2 H, Ar), 7.35 (d, J ϭ
8.7 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3): δ ϭ 29.3, 29.9,
31.6, 104.0, 117.7, 125.6, 127.3, 127.5, 128.2, 132.7 ppm. [M]ϩ
calcd. for C12H10ClNS3: 299, found 299. C12H10ClNS3 (299.9):
calcd. C 48.1, H 3.3; found C 48.1, H 3.5.
31: Yellow solid; 51% yield (0.129 g); m.p. 70 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 2.15Ϫ2.22 (m, 2 H, CH2CH2CH2),
40: Yellow solid; 98% yield (0.290 g); m.p. 90Ϫ91 °C. 1H NMR
3.50Ϫ3.62 (m, 4 H, CH2CH2CH2), 6.20 (s, 1 H, CH), 7.53 (d, J ϭ (250 MHz, CDCl3): δ ϭ 3.21Ϫ3.40 (m, 4 H, CH2CH2), 7.43 (d,
8.6 Hz, 2 H, Ar), 8.08 (d, J ϭ 8.6 Hz, 2 H, Ar) ppm. 13C NMR J ϭ 7.2 Hz, 2 H, Ar), 8.13 (d, J ϭ 7.2 Hz, 2 H, Ar) ppm. 13C NMR
(63 MHz, CDCl3): δ ϭ 29.2, 31.1, 33.3, 123.3, 124.5, 128.1, 131.1, (63 MHz, CDCl3): δ ϭ 31.1, 33.3, 112.7, 123.3, 125.4, 128.1, 132.1,
Eur. J. Org. Chem. 2005, 416Ϫ428
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© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
427

H. Firouzabadi, N. Iranpoor, A. Garzan, H. R. Shaterian, F. Ebrahimzadeh
FULL PAPER
[4]
147.2, 147.9 ppm. [M]ϩ calcd. for C11H8N2O2S3: 296, found 296.
C11H8N2O2S3 (296.4): calcd. C 44.6, H 2.7; found C 44.5, H 2.9.
H. Tani, T. Inamasu, K. Masumoto, R. Tamura, H. Shimizu,
H. Suzuki, Phosphorus, Sulfur and Silicon 1992, 67, 261Ϫ266.
R. Caputo, C. Ferreri, G. Palumbo, Synthesis 1991, 223Ϫ224.
B. Karimi, H. Hazarkhani, Synthesis 2003, 2547Ϫ2551.
H. Firouzabadi, B. Karimi, Phosphorus, Sulfur Silicon 2001,
175, 199Ϫ206.
[5]
[6]
[7]
41: Orange solid; 92% yield (0.285 g); m.p. 86Ϫ88 °C. 1H NMR
(250 MHz, CDCl3): δ ϭ 2.11Ϫ2.23 (m, 2 H, CH2CH2CH2),
3.53Ϫ3.60 (m, 4 H, CH2CH2CH2), 7.55 (d, J ϭ 8.8 Hz, 2 H, Ar),
8.06 (d, J ϭ 8.8 Hz, 2 H, Ar) ppm. 13C NMR (63 MHz, CDCl3):
δ ϭ 26.1, 28.7, 32.2, 116.6, 122.2, 124.6, 126.9, 129.7, 145.1, 145.7
ppm. [M]ϩ calcd. for C12H10N2O2S3: 310, found 310.
C12H10N2O2S3 (310.4): calcd. C 46.4, H 3.2; found C 46.4, H 3.4.
[8]
[9]
H. Firouzabadi, N. Iranpoor, B. Karimi, Synlett 1999,
413Ϫ414.
H. Firouzabadi, N. Iranpoor, H. Hazarkhani, B. Karimi, J.
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M. K. Scott, T. M. Ross, D. H. S. Lee, H. Wang, R. P. Shank,
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Acknowledgments
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We are thankful to the Iran TWAS Chapter Based at ISMO
(ITCBI) and the Shiraz University Research Council for their sup-
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© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
Eur. J. Org. Chem. 2005, 416Ϫ428