Reaction between triphenylphosphine and acetylenic esters or acetylenic ketones in the presence of mercaptoesters

Article abstract of DOI:10.1080/00397910902778027

The reactive diionic intermediate generated by the addition of triphenylphosphine to electron-deficient acetylenic esters or ketones was trapped by mercaptoesters such as mercaptothioglycolate or methyl 3-mercaptopropanoate to produce substituted furans,

Full text of DOI:10.1080/00397910902778027

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Reaction Between
Triphenylphosphine and
Acetylenic Esters or Acetylenic
Ketones in the Presence of
Mercaptoesters
Mohammad H. Mosslemin a , Mohammad Anary-
Abbassinejad a , Alireza Hassanabadi a , Marzieh
Mohebat a & Mohammad R. Nateghi a
a Department of Chemistry , Islamic Azad University,
Yazd Branch , Yazd, Iran
Published online: 04 Sep 2009.
To cite this article: Mohammad H. Mosslemin , Mohammad Anary-Abbassinejad ,
Alireza Hassanabadi , Marzieh Mohebat & Mohammad R. Nateghi (2009) Reaction
Between Triphenylphosphine and Acetylenic Esters or Acetylenic Ketones in the
Presence of Mercaptoesters, Synthetic Communications: An International Journal
for Rapid Communication of Synthetic Organic Chemistry, 39:19, 3482-3492, DOI:
10.1080/00397910902778027
To link to this article: http://dx.doi.org/10.1080/00397910902778027
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Synthetic Communications1, 39: 3482–3492, 2009
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397910902778027
Reaction Between Triphenylphosphine
and Acetylenic Esters or Acetylenic Ketones
in the Presence of Mercaptoesters
Mohammad H. Mosslemin, Mohammad Anary-Abbassinejad,
Alireza Hassanabadi, Marzieh Mohebat, and Mohammad R. Nateghi
Department of Chemistry, Islamic Azad University, Yazd Branch,
Yazd, Iran
Abstract: The reactive diionic intermediate generated by the addition of
triphenylphosphine to electron-deficient acetylenic esters or ketones was trapped
by mercaptoesters such as mercaptothioglycolate or methyl 3-mercaptopropano-
ate to produce substituted furans, vinyl sulfides, or dithioesters.
Keywords: Acetylenic esters, acetylenic ketones, mercaptoesters, substituted
furans, triphenylphosphine
The nucleophilic addition of triphenylphosphine to electron-deficient
triple bonds leads to a highly reactive zwitterionic intermediate, which
may be trapped by various electrophiles. The reaction of triphenylpho-
sphine with dimethyl acetylenedicarboxylate (DMAD) in the presence
of different organic acidic compounds, to trap the diionic intermediate,
has been extensively investigated.[1–3] In the most of these reactions, the
phosphorus ylides were reported as intermediate or final product. How-
ever, there are also many reports on the reaction between triphenylpho-
sphine and acetylenic esters in the presence of an electrophile in which
triphenylphosphine acted as catalyst.[4–7] In fact, in these reactions,
nucleophilic triphenylphosphine connected together the two electrophilic
Received October 17, 2008.
Address correspondence to Mohammad H. Mosslemin, Department of
Chemistry, Islamic Azad University, P. O. Box 8916871967-155, Yazd Branch,
Yazd, Iran. E-mail: mosleminemh@yahoo.com
3482

Sulfur-Substituted Furans
3483
substrates. In continuation of our previous work on the reaction between
trivalent phosphorus nucleophiles with acetylenic esters in the presence of
organic acidic compounds,[8–11] here we report the results of our studies
on the reaction between triphenylphosphine and electron-deficient acety-
lenic ketones or esters in the presence of S-H acidic compounds such as
mercaptothioglycolate or methyl 3-mercaptopropanoate.
Treatment of triphenylphosphine (1), dibenzoylacetylene (2), and
ethyl thioglycolate (3) in dichloromethane (DCM) at room temperature
for 24 h and separation of the reaction mixture by column chromato-
graphy afforded three products: ethyl (2,5-diphenyl-furan-3-ylsulfanyl)
acetate 4a (50% yield), ethyl (1-benzoyl-3-oxo-3-phenyl-propenylsulfanyl)
acetate 4b (10% yield), and ethyl (1-benzoyl-3-oxo-3-phenyl-propyl-
sulfanyl)acetate 4c (10% yield) (Scheme 1).
The structure of products was elucidated from their elemental analy-
1
sis, H NMR, 13C NMR, infrared (IR) spectroscopic, and mass spectral
data. The 1H NMR spectrum of compound 4a exhibited two singlets at d
3.51 and 6.95 ppm for methylene protons and the proton of furan ring,
respectively. A triplet (d ¼ 1.24 ppm) and a quartet (d ¼ 4.21 ppm) were
observed for ethyl protons. Aromatic protons appeared as multiplets
at d ¼ 7.34–8.22 ppm. 13C NMR spectrum of compound 4a exhibited 16
Scheme 1. Reaction of dibenzoylacetylene, triphenylphosphine, and ethyl
thioglycolate.

3484
M. H. Mosslemin et al.
distinct signals, in agreement with the proposed structure. No signal was
observed at more than 169 ppm, indicating the absence of a ketone group.
The IR spectrum of compound 4a showed the carbonyl group absorption
bond at 1735 cmꢀ1. The mass spectrum of compound 4a showed a mole-
cular ion peak at 338.
For compound 4b, the chemical shift for the olefinic proton can be
used to determine the geometry of double bond.[12] The chemical shift
of 7.23 ppm of the olefinic proton is consistent with the Z-geometry of
the carbon–carbon double bond in compound 4b.
1H NMR spectrum of compound 4c showed three doublets of
doublets at d 3.52, 4.04, and 5.01 ppm for methylene and methine pro-
tons, forming an AMX spinning system. The diastereotopic protons of
methylene group attached to sulfur atom resonated at d ¼ 3.30 ppm as
an AB quartet.
On the basis of the well-established chemistry of trivalent phos-
phorus compounds,[3,7–9] it is reasonable to assume that compound 4a
was obtained from the initial addition of triphenylphosphine to dibenzoy-
lacetylene and subsequent protonation of the reactive diionic adduct by
ethyl thioglycolate, followed by the attack of thiolate anion to phospho-
nium cation to furnish ylide 5. Rearrangement of ylide 5 followed by
elimination of triphenylphosphinoxide resulted in compound 4a
(Scheme 2). Phosphorane 5 may be hydrolized to sulfide 4c or converted
to vinylsulfide 4b by elimination of triphenylphosphine (Scheme 3).
From the reaction of triphenylphosphine, dibenzoylacetylene, and
methyl 3-mercaptopropanoate, sulfur-substituted furan 7a and isomeric
mixtures of vinyl sulfide 7b were obtained in 65% and 23% yields, respec-
tively (Scheme 4). The chemical shift for the olefinic proton of compound
7b was used to determine the geometry of the double bond.[12] The
Scheme 2. Suggested mechanism for formation of compound 4a.

Sulfur-Substituted Furans
3485
Scheme 3. Suggested mechanism for formation of compounds 4b and 4d.
1H NMR, 13C NMR, and IR spectra of compounds 7a and 7b exhibited
the characteristic signals and absorption bonds similar to compounds 4a
and 4b, respectively (see the Experimental Section).
In similar conditions, the reaction of dialkyl acetylenedicarboxylates
and triphenylphosphine in the presence of ethyl thioglycolate was stu-
died. Treatment of triphenylphosphine (1), dimethyl acetylenedicarboxy-
late (DMAD, 8a), and ethyl thioglycolate (3) in DCM at room
temperature for 24 h and separation of the reaction mixture by column
chromatography led to two products: dimethyl 2-(ethoxycarbonyl-methyl
sulfanyl)-2-butenoate (9a) and dimethyl 2,2-bis-(ethoxycarbonyl-methyl
sulfanyl)succinate (10a) in 65 and 15% yield, respectively (Scheme 5).
Two ethoxycarbonyl-methyl sulfanyl groups are enantiotopic, and four
signals for their carbons were obsereved in the 13C NMR spectrum of
Scheme 4. Reaction of dibenzoylacetylene, triphenylphosphine, and methyl
3-mercaptopropanoate.

3486
M. H. Mosslemin et al.
Scheme 5. Reaction of dialkyl acetylenedicarboxylate, triphenylphosphine, and
ethyl thioglycolate.
compound 10a, so 10 signals were observed in 13C NMR spectrum of
compound 10a, in agreement with the proposed structure. However, the pro-
tons of methylene groups connected to sulfur atoms are diastereotopic, and a
multiplet was observed for them in the 1H NMR spectrum of compound 10a.
The protons of the methylene group connected to quaternary carbon atom
are enantiotopic, and a single signal was observed for them at d ¼ 3.81 ppm.
A reasonable mechanism for formation of compound 9a is similar to
that explained for compound 4a (Scheme 2). Compound 10 was probably
formed from the Michael addition of another molecule of ethyl thiogly-
colate to vinylsulfide 9. When the reaction was carried out with 2 equiva-
lents of ethyl thioglycolate, compound 10a was obtained in 95% yield as
the only product. As shown in Scheme 5, the reaction was applicable for
other acetylene diesters, such as diethyl or ditertiobutyl acetylenedicar-
boxylate, and products 9b and c and 10b and c were obtained.
Under similar conditions, the reaction of thiophenol was examined
with acetylenic esters or ketones in the presence of triphenylphosphine,
but no product was obtained.
In conclusion, the reaction of dibenzoylacetylene, triphenylpho-
sphine, and ethylthioglycolate or methyl 3-mercaptopropanoate furn-
ished a simple one-pot route to sulfur-substituted furans as main
product. A similar reaction with dialkyl acetylendicarboxylates, instead
of dibenzoylacetylene, resulted in vinylsulfides in moderate yields and

Sulfur-Substituted Furans
3487
dithioacetals as minor product. In this method, not only was the reaction
performed under neutral conditions but also the starting materials and
reagents can be mixed without any activation or modification.
EXPERIMENTAL
Elemental analyses were performed using a Heraeus CHN-O-Rapid
analyzer. Mass spectra were recorded on a Finnigan-Mat 8430 mass
spectrometer operating at an ionization potential of 70 eV. IR spectra
1
were recorded on a Shimadzu IR-470 spectrometer. H and 13C NMR
spectra were measured with a Bruker DRX-500 Avance spectrometer at
1
500 and 125.8 MHz, respectively. H and 13C spectra were obtained on
solution in CDCl3 using tetramethylsilane (TMS) as internal standard.
Dibenzoylacetylene was prepared by addition of acetylenedimagnesium-
dibromide[10] to benzaldehyde and oxidation of the obtained diol.[11]
Other chemicals used in this work were purchased from Fluka (Buchs,
Switzerland).
General Procedure
A mixture of acetylenic compound (2 mmol) in 5 ml DCM was added to a
magnetically stirred solution of mercaptoester (2 mmol) and triphenyl-
phosphine (2 mmol) in 10 ml DCM at room temperature over 10 min.
The reaction mixture was then allowed to stir for 24 h. The solvent was
removed under reduced pressure, and the residue was purified by
silica-gel (Merck silica gel 60, 230–400 mesh) column chromatography
using hexane–ethyl acetate as eluent.
Data
Ethyl (2,5-Diphenyl-furan-3-yl-sulfanyl) Acetate (4a)
Yellow oil; yield 0.34 g (50%). IR (KBr) (nmax=cmꢀ1): 1735 (C¼O). MS,
m=z (%): 338 (Mþ, 75), 223 (74), 105 (COPh, 83), 77 (Ph, 100). Anal.
calcd. for C20H18O3S (338.4): C, 70.98; H, 5.36. Found: C, 70.9; H,
1
3
5.5%. H NMR (500 MHz, CDCl3): d ¼ 1.24 (3 H, t JHH 7 Hz, CH3),
3.51 (2 H, s, SCH2), 4.21 (2 H, q 3JHH 7 Hz, OCH2), 6.95 (1 H, s, olefinic
CH), 7.34–8.22 (10 H, m, 2 C6H5). 13C NMR (125.8 MHz, CDCl3):
d ¼ 13.8 (CH3), 37.4 (SCH2), 61.3 (OCH2), 111.4, 113.0, 151.8, and

3488
M. H. Mosslemin et al.
152.3 (furan moiety), 123.7, 125.7, 127.7, 127.7, 128.3, 128.7, 129.8, and
130.1 (2 C6H5), 169.3 (CO).
Ethyl (1-Benzoyl-3-oxo-3-phenyl-propenylsulfanyl) Acetate (4b)
Yellow oil; yield 0.07 g (10%). IR (KBr) (nmax=cmꢀ1): 1744 (C¼O, ester),
1668, and 1641 (2 C¼O, ketone). MS, m=z (%): 354 (Mþ, 89), 267 (74),
235 (81), 105 (COPh, 100), 77 (Ph, 99). Anal. calcd. for C20H18O4S
(354.4): C, 67.78; H, 5.12. Found: C, 67.6; H, 5.1%. 1H NMR
3
(500 MHz, CDCl3): d ¼ 1.31 (3 H, t JHH 7 Hz, CH3), 3.64 (2 H, s,
3
SCH2), 4.23 (2 H, q JHH 7 Hz, OCH2), 7.23 (1 H, s, CH), 7.32–8.20
(10 H, m, 2 C6H5). 13C NMR (125.8 MHz, CDCl3): d ¼ 13.8 (CH3),
33.9 (SCH2), 62.2 (OCH2), 117.7 and 156.7 (olefinic carbons), 128.4,
128.6, 129.6, 129.7, 132.9, 133.6, 134.5, and 136.8 (2 C6H5), 167.6 (CO
ester), 185.1 and 193.0 (2 CO ketone).
Ethyl (1-Benzoyl-3-oxo-3-phenyl-propylsulfanyl) Acetate (4c)
Yellow oil; yield 0.07 g (10%). IR (KBr) (nmax=cmꢀ1): 1730 (C¼O, ester),
1676 (C¼O, ketone). MS, m=z (%): 356 (Mþ, 2), 223 (24), 105 (COPh,
100), 77 (Ph, 99). Anal. calcd. for C20H20O4S (356.4): C, 67.39; H,
1
5.66. Found: C, 67.3; H, 5.7%. H NMR (500 MHz, CDCl3): d ¼ 1.31
3
(3 H, t JHH 7 Hz, CH3), 3.30 (2 H, AB-quartet, SCH2), 3.52 (1 H, dd
3
2
3
2JHH 18 Hz, JHH 4 Hz, HCH), 4.04 (1 H, dd JHH 18 Hz, JHH 10 Hz,
3
3
3
HCH), 4.22 (2 H, q JHH 7 Hz, OCH2), 5.01 (1 H, dd JHH 4 Hz, JHH
10 Hz, CH), 7.41–7.75 (6 H, m, 6CH), 7.91 (2 H, d 3JHH 8 Hz, 2 CHortho),
8.13 (2 H, d JHH 8 Hz, 2 CHortho). 13C NMR (125.8 MHz, CDCl3):
3
d ¼ 14.0 (CH3), 31.8 (SCH2), 41.3 and 41.4 (CH and CH2), 61.7
(OCH2), 128.1, 128.6, 128.7, 128.8, 133.3, 133.5, 135.6 and 136.0 (2
C6H5), 163.9, 188.9, and 191.3 (3 CO).
Methyl 3-(2,5-Diphenyl Furan-3-ylsulfanyl) Propanoate (7a)
Yellow oil; yield 0.44 g (65%). IR (KBr) (nmax=cmꢀ1): 1735 (C¼O). MS,
m=z (%): 338 (Mþ, 77), 223 (63), 105 (COPh, 55), 77 (Ph, 100). Anal.
calcd. for C20H18O3S (338.4): C, 70.98; H, 5.36. Found: C, 70.9; H,
1
3
5.2%. H NMR (500 MHz, CDCl3): d ¼ 2.62 and 3.13 (4 H, 2 t JHH
7 Hz, 2 CH2), 3.72 (3 H, s, CH3), 6.80 (1 H, s, CH), 7.29–8.18 (10 H,
m, 2 C6H5). 13C NMR (125.8 MHz, CDCl3): d ¼ 30.4 and 33.1 (2 CH2),
51.7 (CH3), 111.5, 113.5, 151.9 and 152.5 (furan moiety), 123.8, 125.8,
127.8, 127.9, 128.4, 128.9, 130.4, 130.5 (2 C6H5), 169.3 (CO).

Sulfur-Substituted Furans
3489
Methyl 3-(1-Benzoyl-3-oxo-3-phenylpropenylsulfanyl) Propanoate (7b)
Yellow oil; yield 0.16 g (23%). IR (KBr) (nmax=cmꢀ1): 1731 (C¼O, ester),
1665, and 1633 (2 C¼O, ketone). MS, m=z (%): 354 (Mþ, 81), 267 (84),
235 (90), 105 (COPh, 100), 77 (Ph, 99). Anal. calcd. for C20H18O4S
(354.4): C, 67.78; H, 5.12. Found: C, 67.6; H, 5.1%. NMR data for Z
1
isomer (65%): H NMR (500 MHz, CDCl3): d ¼ 2.49 and 2.81 (4 H, 2 t
3JHH 8 Hz, 2 CH2), 3.57 (3 H, s, CH3), 7.11 (1 H, s, olefinic proton),
7.31–8.16 (10 H, m, 2 C6H5). 13C NMR (125.8 MHz, CDCl3): d ¼ 27.0
and 33.9 (2 CH2), 51.9 (CH3), 117.0 and 158.7 (olefinic carbons), 128.1,
128.7, 129.1, 130.1, 132.8, 134.2, 133.7, and 137.7 (2 C6H5), 171.3, 188.2,
1
and 191.8 (3 CO); NMR data for E isomer (25%): H NMR (500 MHz,
3
CDCl3): d ¼ 2.69 and 3.15 (4 H, 2 t JHH 8 Hz, 2 CH2), 3.73 (3 H, s,
CH3), 6.89 (1 H, s, olefinic proton), 7.27–8.26 (10 H, m, 2 C6H5). 13C
NMR (125.8 MHz, CDCl3): d ¼ 26.7 and 33.4 (2 CH2), 52.1 (CH3), 117.5
and 158.1 (olefinic carbons), 128.1, 1285, 128.7, 128.8, 133.2, and 134.8,
133.5, and 137.0 (2 C6H5), 171.4, 185.3, and 193.3 (3 CO).
Dimethyl 2-Ethoxycarbonylmethylsulfanyl-2-butenoate (9a)
Yellow oil; yield 0.16 g (65%). IR (KBr) (nmax=cmꢀ1): 1720 (broad, 3C¼O
ester), 1583 (C¼C). MS, m=z (%): 263 (Mþ þ 1, 81), 231 (Mþ ꢀ OCH3,
100), 216 (231-CH3, 30), 189 (Mþ ꢀ CO2Et, 50). Anal. calcd. for
C10H14O6S (262.3): C, 45.79; H, 5.38. Found: C, 45.6; H, 5.3%. NMR data
1
3
for Z isomer (60%): H NMR (500 MHz, CDCl3): d ¼ 1.29 (3 H, t JHH
7 Hz, CH3), 3.70 (2 H, s, CH2), 3.65 and 3.79 (6 H, 2 s, 2 OCH3), 4.32
(2 H, q JHH 7 Hz, OCH2), 6.97 (1 H, s, CH); 13C NMR (125.8 MHz,
3
CDCl3): d ¼ 12.1 (CH3), 34.2 (CH2), 52.1 and 52.2 (2 OCH3), 62.4
(OCH2), 122.3 (CH), 147.2 (C), 168.2, 169.3, and 171.8 (3 CO); NMR data
1
3
for E isomer (40%): H NMR (500 MHz, CDCl3): d ¼ 1.39 (3 H, t JHH
7 Hz, CH3), 3.64 (2 H, s, CH2), 3.67 and 4.15 (6 H, 2 s, 2 OCH3), 4.21
(2 H, q JHH 7 Hz, OCH2), 6.21 (1 H, s, CH); 13C NMR (125.8 MHz,
3
CDCl3): d ¼ 12.3 (CH3), 34.0 (CH2), 51.7 and 52.4 (2 OCH3), 62.1
(OCH2), 122.7 (CH), 146.2 (C), 168.0, 169.0, and 172.3 (3 CO).
Diethyl 2-Ethoxycarbonylmethylsulfanyl-2-butenoate (9b)
Yellow oil; yield 0.42 g (73%). IR (KBr) (nmax=cmꢀ1): 1733 (broad, 3
C¼O ester), 1583 (C¼C). MS, m=z (%): 291 (Mþ þ 1, 20), 245 (Mþ ꢀ OEt,
100), 216 (245-Et, 25). Anal. calcd. for C12H18O6S (290.3): C, 49.64; H,
6.25. Found: C, 49.6; H, 6.3%. NMR data for Z isomer (65%): 1H
NMR (500 MHz, CDCl3): d ¼ 1.21–1.78 (9 H, m, 3 CH3), 3.88 (2 H, s,

3490
M. H. Mosslemin et al.
SCH2), 4.15–4.71 (6 H, m, 3 OCH2), 6.89 (1 H, s, CH); 13C NMR
(125.8 MHz, CDCl3): d ¼ 13.5, 13.5, and 14.0 (3 CH3), 35.0 (SCH2),
60.9, 61.4, and 62.5 (3 OCH2), 122.3 (CH), 147.8 (C), 165.3, 166.2, and
170.9 (3 CO); NMR data for E isomer (25%): 1H NMR (500 MHz,
CDCl3): d ¼ 1.21–1.78 (9 H, m, 3 CH3), 3.71 (2 H, s, SCH2), 4.15–4.71
(6 H, m, 3 OCH2), 6.01 (1 H, s, CH); 13C NMR (125.8 MHz, CDCl3):
d ¼ 13.6, 13.7, and 13.8 (3 CH3), 33.2 (SCH2), 60.1, 61.8, and 62.4 (3
OCH2), 114.3 (CH), 148.8 (C), 163.3, 165.3, and 168.3 (3 CO).
Di-tert-butyl 2-Ethoxycarbonylmethylsulfanyl-2-butenoate (9c)
Yellow oil; yield 0.16 g (68%). IR (KBr) (nmax=cmꢀ1): 1737 (broad, 3C¼O
ester), 1530 (C¼C). MS, m=z (%): 346 (Mþ þ 1, 3), 290 (Mþ ꢀ C4H8, 5),
234 (20), 57 (C4H9, 100). Anal. calcd. for C16H26O6S (346.4): C, 55.47; H,
1
7.56. Found: C, 55.5; H, 7.4%. NMR data for Z isomer (55): H NMR
(500 MHz, CDCl3): d ¼ 1.07–1.80 (21 H, m, 7 CH3), 3.84 (2 H, s,
3
SCH2), 4.11 (2 H, q, JHH 7 Hz, OCH2), 6.75 (1 H, s, CH); 13C NMR
(125.8 MHz, CDCl3): d ¼ 13.2 (CH3), 28.0 and 28.1 (6 CH3), 33.8
(SCH2), 62.1 (OCH2), 82.3 and 84.1 (2 OC), 123.1 (CH), 148.2 (C),
163.1, 165.2, and 170.8 (3 CO); NMR data for E isomer (45): 1H
NMR (500 MHz, CDCl3): d ¼ 1.07–1.80 (21 H, m, 7 CH3), 3.63 (2 H,
3
s, SCH2), 4.35 (2 H, q, JHH 7 Hz, OCH2), 5.78 (1 H, s, CH); 13C
NMR (125.8 MHz, CDCl3): d ¼ 13.3 (CH3), 28.2 (3 CH3), 28.3 (3
CH3), 34.1 (SCH2), 62.4 (OCH2), 81.7 and 83.1 (2 OC), 119.8 (CH),
147.70 (C), 162.8, 164.5, and 170.1 (3 CO).
Dimethyl 2,3-Bis-ethoxycarbonylmethylsulfanylsuccinate (10a)
Yellow oil; yield 15%. IR (KBr) (nmax=cmꢀ1): 1723 (C¼O). Anal. calcd.
for C14H23O8S2(382.45): C, 43.97; H, 5.80. Found: C, 43.8; H, 5.7%.
1
MS (m=z, %): 383 (M þ 1, 66), 266 (100), 231 (99), 145 (79). H NMR
3
(500 MHZ, CDCl3): d ¼ 1.32 (6 H, t JHH ¼ 7 HZ, 2 CH3), 3.36–3.53
(4 H, m, 2 SCH2), 3.71 and 3.79 (6 H, 2 s, 2 OCH3), 3.81 (2 H, s,
3
CH2), 4.25 (4 H, q JHH ¼ 7 HZ, 2 OCH2).13C NMR (125.8 MHz,
CDCl3): d ¼ 14.1 (2 CH3), 33.3 (2 SCH2), 47.0 (CH2), 47.3 (C), 52.7
and 52.8 (2 OCH3), 61.7 (2 OCH2), 169.3, 169.4, and 169.8 (4 C¼O).
Diethyl 2,3-Bis-ethoxycarbonylmethylsulfanylsuccinate (10b)
Yellow oil; yield 0.10 g (12%). IR (KBr) (nmax=cmꢀ1): 1726 (C¼O), MS,
m=z (%): 411 (Mþ þ 1, 15), 337 (Mþ ꢀ CO2Et, 11), 291 (Mþ-SCH2CO2Et,

Sulfur-Substituted Furans
3491
77), 245 (291-OEt, 100). Anal. calcd. for C16H26O8S2 (410.50): C, 46.81;
H, 6.38. Found: C, 46.8; H, 6.3%. 1H NMR (500 MHz, CDCl3): d ¼ 1.21–
1.84 (12 H, 4 CH3), 3.54 (4 H, AB-quartet, 2 SCH2), 3.79 (2 H, s, CH2),
4.10–4.67 (8 H, m, 4 OCH2). 13C NMR (125.8 MHz, CDCl3): d ¼ 13.6
and 14.0, 14.1 (4 CH3), 32.2 (2 SCH2), 47.1 (CH2), 47.5 (C), 61.4, 61.6,
and 61.7 (4 OCH2), 169.30, 170.3, and 170.5 (4 CO).
Di-tert-butyl 2,3-Bis-ethoxycarbonylmethylsulfanylsuccinate (10c)
Yellow oil; yield 0.09 g (10%). IR (KBr) (nmax=cmꢀ1): 1730 (C¼O), MS,
m=z (%): 466 (Mþ, 4), 411 (Mþ ꢀ C4H7, 20), 57 (C4H9, 100). Anal. calcd.
1
for C20H34O8S2 (466.6): C, 51.48; H, 7.34. Found: C, 51.7; H, 7.3%. H
NMR (500 MHz, CDCl3): d ¼ 1.18–1.80 (24 H, 8 CH3), 3.4 (2 H, s,
3
CH2), 3.75 (4 H, AB-quartet, 2 SCH2), 4.33 (2 H, q, JHH 7 Hz,
OCH2). 13C NMR (125.8 MHz, CDCl3): d ¼ 13.1 (CH3), 29.0 and 29.0
(6 CH3), 33.0 (SCH2), 47.9 (C), 48.2 (CH2), 62.1 (OCH2), 83.2 and 82.4
(2 OC), 169.7, 170.2, and 170.6 (4 CO).
REFERENCES
1. Corbridge, D. E. C. Phosphorus: An Outline of the Chemistry, Biochemistry,
and Uses, 5th ed.; Elsevier: Amsterdam, 1995.
2. Yavari, I.; Adib, M.; Hojabri, L. Vinyltriphenylphosphonium salt-mediated
serendipitous synthesis of aryliminophosphoranes. Tetrahedron 2002, 58,
7213.
3. Engel, R. Synthesis of Carbon-Phosphorus Bonds; CRC Press: Boca Raton,
FL, 1988.
4. Trost, B. M.; Dake, G. R. Nucleophilic a-addition to alkynoates: A synthesis
of dehydroamino acids. J. Am. Chem. Soc. 1997, 119, 7595.
5. Nair, V.; Nair, J. S.; Vinod, A. U.; Rath, N. P. Triphenylphosphine-
promoted addition of dimethyl acetylenedicarboxylate to 1,2-benzoquinones:
Facile synthesis of novel c-spirolactones. J. Chem. Soc., Perkin Trans. 1 1997,
3129.
6. Yavari, I.; Hekmat-Shoar, R.; Zonouzi, A. A new and efficient route to 4-
carboxymethylcoumarins mediated by vinyltriphenylphosphonium salt.
Tetrahedron Lett. 1998, 39, 2391.
7. Yavari, I.; Adib, M.; Hojabri, L. Vinyltriphenylphosphonium salt-mediated
synthesis of functionalized coumarins. Tetrahedron 2001, 57, 7537.
8. Anary-Abbasinejad, M.; Rostami, N.; Parhami, A.; Hassanabadi, A. Synth-
esis of functionalised phosphonates by three-component reaction between
phosphites, dialkyl acetylenedicarboxylates, and pyrrole, indole, or benzo-
triazole. J. Chem. Res. 2007, 291.

3492
M. H. Mosslemin et al.
9. Anary-Abbasinejad, M.; Hassanabadi, A.; Anaraki-Ardakani, H. One-pot
synthesis of stable phosphite ylides by three-component reaction between
acetylenic esters, aldehyde semicarbazones, and tributyl- or triethyl
phosphite. J. Chem. Res. 2007, 455.
10. Anaraki-Ardakani, H.; Sadeghian, S.; Rastegari, F.; Hassanabadi, A.;
Anary-Abbasinejad, M. Three-component reaction of triphenylphosphine,
acetylenic esters, and arylsulfonyl hydrazides or arylhydrazines: An efficient
one-pot synthesis of stable b-nitrogen-substituted phosphorus ylides. Synth.
Commun. 2008, 38 (12), 1990.
11. Anary-Abbasinejad, M.; Anaraki-Ardakani, H.; Hosseini-Mehdiabad, H.
One-pot synthesis of stable phosphorus ylides by three-component reaction
between dimethyl acetylenedicarboxylate, semicarbazones, and triphenylpho-
sphine. Phosphorus, Sulfur Silicon Relat.Elem. 2008, 183 (6), 1440.
12. Eliel, E. L.; Wilen, S. H.; Mander, L. N. In Stereochemistry of Organic
Compounds; Wiley: New York, 1994; p. 569.