Sm(OTf)3as a highly efficient catalyst for the synthesis of 2,3-unsaturated O- and S-pyranosides from glycals and the temperature-dependent formation of 4-O-acetyl-6-deoxy-2,3-unsaturated S-pyranosides and 4-O-acetyl-6-deoxy-3-alkylthio glycals

Article abstract of DOI:10.1016/j.tet.2014.09.060

By using Sm(OTf)₃as the catalyst, synthesis of 2,3-unsaturated-glycosides has been performed. A series of 2,3-unsaturated glycosides were obtained from 3,4,6-tri-O-acetyl-d-glucal or 3,4-di-O-acetyl-l-rhamnal under mild reaction conditions in g

Full text of DOI:10.1016/j.tet.2014.09.060

Tetrahedron 70 (2014) 8505e8510
Contents lists available at ScienceDirect
Tetrahedron
journal homepage: www.elsevier.com/locate/tet
Sm(OTf)3 as a highly efficient catalyst for the synthesis
of 2,3-unsaturated O- and S-pyranosides from glycals and the
temperature-dependent formation of 4-O-acetyl-6-deoxy-2,3-
unsaturated S-pyranosides and 4-O-acetyl-6-deoxy-3-alkylthio
glycals
,
b
,
a
Peiran Chen a , Dalin Zhang
*
a Key Lab of Eco-Textile, The Ministry of Education, Donghua University, 2999 Renmin Road North, Songjiang District, Shanghai 201620, China
b Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, CAS, Shanghai 200032, China
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 24 July 2014
Received in revised form 15 September 2014
Accepted 22 September 2014
Available online 28 September 2014
By using Sm(OTf)3 as the catalyst, synthesis of 2,3-unsaturated-glycosides has been performed. A series
of 2,3-unsaturated glycosides were obtained from 3,4,6-tri-O-acetyle
rhamnal under mild reaction conditions in good yield and high anomeric selectivity. It was found that
under certain conditions, reaction of 3,4-di-O-acetyl- -rhamnal with thiol leads to temperature-
D-glucal or 3,4-di-O-acetyl-L-
L
dependent formation of C-1-S and C-3-S product. A temperature-dependent profile of the yield of
these two products is given.
Keywords:
Sm(OTf)3
Ó 2014 Elsevier Ltd. All rights reserved.
3,4,6-Tri-O-acetyl-D-glucal
3,4-Di-O-acetyl- -rhamnal
L
C-1-S and C-3-S glycopyranoside
Ferrier rearrangement
1. Introduction
etc.7 Most of those researches concentrated on using 3,4,6-tri-O-
acetyl-D-glucal as substrate and the reactions had to promoted by
Alkyl and aryl 2,3-unsaturated glycosides are capable of versa-
tile chemical transformations, therefore they are important chiral
intermediates in the synthesis of biologically active molecules1 and
new functional materials.2 Ferrier rearrangement is an efficient and
facile reaction for the synthesis of 2,3-unsaturated glycopyrano-
sides.3 A variety of reagents have been used to promote this re-
action, including Bronsted acids, such as H2SO4, H3PO4,
HClO4eSiO2, TfOHeSiO2, etc.4 Lewis acids, such as BF3$OEt2, FeCl3,
Fe2(SO4)3, Fe(NO3)3, InCl3, BiCl3, CeCl3, ZnCl2, Pd(OAc)2, ZrCl4,
ionic solvent.7c,7fei In our continuing efforts to search for more ef-
ficient catalyst for Ferrier Rearrangement, we found Sm(OTf)3 was
a highly efficient catalyst for our purposes. Here we wish to report
our result.
2. Results and discussion
2.1. Optimization of reaction conditions
K5CoW12O40$3H2O, Bi(OTf)3, Sc(OTf)3, Fe(OTf)3, TiCl4, AuCl3,
Considering the effect of anions in the salts on the catalytic
capacity,5u,5v we screened several samarium salts, including SmCl3,
Sm(NO3)3, SmI2, and Sm(OTf)3 and found Sm(OTf)3 was the best
one. For the reaction solvent, we found acetonitrile gave the best
result among acetone, acetonitrile, THF, diethyl ether, and toluene.
HBF4eSiO2, ZnCl2/Al2O3, TiCl3(OTf), RuCl35 as well as oxidants, such
as I2, IDCP, NIS, and DDQ, etc.6 In recent years, due to their special
properties and high catalytic activities, lanthanide elements as
catalyst have got more and more application. Among lanthanides,
which have been employed as the catalysts in Ferrier Rearrange-
ment, there can be mentioned Dy(OTf)3, Er(OTf)3, and Yb(OTf)3,
2.2. Synthesis of O-2,3-unsaturated glucosides
This section discusses the synthesis of O-alkyl and O-aryl 2,3-
unsaturated glycosides. The reaction was carried out under mild
conditions. The substrate alcohols included simple alcohol and
* Correspondingauthor. Tel.:þ862167792594;e-mail address: prchen@dhu.edu.cn
(P. Chen).
http://dx.doi.org/10.1016/j.tet.2014.09.060
0040-4020/Ó 2014 Elsevier Ltd. All rights reserved.

8506
P. Chen, D. Zhang / Tetrahedron 70 (2014) 8505e8510
Table 2 (continued)
chiral alcohols. The reaction time was short and the yield was good
b
for two types of the examined glycals: 3,4,6-tri-O-acetyl
and 3,4-di-O-acetyl- -rhamnal. (Table 1 and Table 2) Similar results
were gained for the phenol substrates. A report mentioned that
when tri-O-acetyl- -glucal was treated with p-methoxyphenol in
CH2Cl2 with BF3$OEt2 as the catalyst, C-glucoside was obtained
exclusively.8 However, in our case, no such phenomenon occurred.
p-Methoxyphenol gave the normal product O-glucoside in good
yield (entry 7), which could be confirmed by the two ortho aromatic
signals in the product 1H NMR.
D-glucal
Entry
5
ROH
Reaction time (min)
20
Product yield (%)a(
a:b)
L
5e: 71 (
a
only)
only)
D
OH
6
30
20
5f: 62 (a
H
CO
OH
7
5g: 64 (
a
only)
a
Isolated yield.
b
The anomeric ratio was determined by integration of the anomeric hydrogen in
the 1H NMR spectra.
Table 1
Synthesis of O-alkyl and O-aryl 2,3-unsaturated glucosides from tri-O-acetyl-D-
glucal
2.3. Synthesis of S-alkyl 2,3-unsaturated glycosides
AcO
AcO
This section discusses the reaction of 3,4,6-tri-O-acetyl-D-glucal
and 3,4-di-O-acetyl-L-rhamnal with thiols. As showed in Table 3,
similar to the case of O-glycosidation, the reaction was carried out
under mild conditions in short reaction time with good yield.
O
O
Sm(OTf)3 (10 mmol%)
MeCN, 40oC
OAc
+
ROH
OR
AcO
AcO
1
2
3
b
Entry
ROH
EtOH
OH
Reaction time (min)
10
Product yield (%)a(
a:b)
Table 3
1
3a: 88 (33:1)
Synthesis of S-alkyl 2,3-unsaturated glycosides from 3,4,6-tri-O-acetyl-
3,4-di-O-acetyl- -rhamnal
D-glucal and
L
2
10
10
3b: 85 (10:1)
HO
3
4
3c: 78 (a only)
O
H
Entry
Starting
material
R0SH
Reaction
time (min)
Product yield
40
3d: 72 (7:1)
3e: 69 (7:1)
H
H
b
(%)a(
7a: 86 (
a
:
b)
HO
1
2
1
1
EtSH
n-C12H25SH
10
20
a
a
only)
only)
7b: 83 (
O
O
HO
5
6
10
30
3
4
1
4
20
20
7c: 81 (
a
only)
O
O
O
EtSH
7d (C-1-S product):
8d (C-3-S product)
See Table 4
OH
3f: 67 (
a
only)
5
4
n-C12H25SH
20
7e (C-1-S product):
8e (C-3-S product)
See Table 4
7
8
20
30
3g: 75 (
a
only)
only)
H
CO
OH
OH
6
4
20
7f: 73 (17:1)
3h: 73 (
a
a
Isolated yield.
a
b
Isolated yield.
The anomeric ratio was determined by integration of the anomeric hydrogen in
b
the 1H NMR spectra.
The anomeric ratio was determined by integration of the anomeric hydrogen in
the 1H NMR spectra.
It was reported that reaction of some kind of glucals with thiols
3
in the presence of BF3$OEt2,9a,b diluted hydrochloric acid9c or SnCl4
Table 2
in CH2Cl2 gave 1-S glucoside as the major product and 3-S glucal as
Synthesis of O-alkyl and O-aryl 2,3-unsaturated glycosides from 3,4-di-O-acetyl-L-
the minor product (Scheme 1).
rhamnal
OAc
AcO
Me
Sm(OTf)3
O
O
(10 mmol%)
+
ROH
OR
Me
MeCN, 40oC
OAc
2
b
Entry
1
ROH
Reaction time (min)
10
Product yield (%)a(
a:b)
Scheme 1. Literature reported reaction of glucal with thiol giving 1-S-glucoside and 3-
S-glucal.
EtOH
5a: 77 (9:1)
OH
2
3
10
10
5b: 65 (
a
only)
only)
This was also true in our case. When 3,4-di-O-acetyl-L-rhamnal
was reacted with EtSH or n-C12H25SH, two products formed. It was
found that C-1-S products (7e, 7f) were the major products at lower
reaction temperature, while C-3-S products (8e, 8f) increased as the
reaction temperature elevated. Table 4 collected the yields chang-
ing at varying reaction temperature. However, in the case of 3,4,6-
HO
5c: 72 (
a
4
10
5d: 70 (6:1)
tri-O-acetyl-D-glucal, formation of C-3-S product was not detected

P. Chen, D. Zhang / Tetrahedron 70 (2014) 8505e8510
8507
Table 4
Reaction of 3,4-di-O-acetyl-L-rhamnal with two alkythiols
OAc
O
CH
3
OAc
O
OAc
O
Sm(OTf) (10 mmol%)
3
+
R'SH
SR'
CH
CH
3
3
+
MeCN
OAc
8
SR'
6
4
7
R' = CH CH - and n-C
H -
12 25
3
2
b
Entry
R0SH
Reaction temperature (ꢀC)
Reaction time (min)
Product yielda C-1-S (7)/C-3-S(8)
Total yield (%)/C-1-S(7): (a:b)
1
2
3
4
5
6
7
8
9
EtSH
EtSH
EtSH
EtSH
ꢃ20
ꢃ5
0
25
40
ꢃ5
0
90
60
40
20
10
70
50
30
10
76.5(7e)/2.5(8e)
67.4(7e)/5.6(8e)
40.9(7e)/24.1(8e)
10.1(7e)/60.9(8e)
6.4(7e)/70.6(8e)
72.1(7f)/2.9(8f)
38.1(7f)/23.8(8f)
8.8(7f)/57.2(8f)
6(7f)/66(8f)
79(14:1)
73(14:1)
65(14:1)
71(14:1)
77(14:1)
75(10:1)
62(10:1)
66(10:1)
72(10:1)
EtSH
n-C12H25SH
n-C12H25SH
n-C12H25SH
n-C12H25SH
25
40
a
Yield is determined by analysis of the 1H NMR spectra of the product mixture.
b
The anomeric ratio was determined by integration of the anomeric hydrogen in the 1H NMR spectra.
even under reflux in acetonitrile. We also noticed that in a work by
Schmidt and co-worker, 3,4,6-tri-O-acetyl-D-glucal reacted with n-
EI ionization at 70 eV. High-Resolution mass spectral (ESI) analyses
were performed on a Finnigan-MAT-8430 spectrometer. IR spectra
were recorded on a Nicolet 380 spectrometer. Optical rotations
were measured by WZZ-2 polarimeter. Melting points were mea-
sured on a WRS-2A melting point apparatus. The glycals, epian-
C8H17SH or PhSH in CH2Cl2 promoted by Yb(OTf)3 at room tem-
perature, no C-3-product formation was reported.7d
Data in Table 3 are presented as curves in Fig. 1, which clearly
showed the formation of C-1-S and C-3-S products is reaction
temperature-dependent. It implies that the C-3-S product is ther-
modynamically more stable.
drosteron,
L
-menthol, (1R)-endo-(þ)-fenchol and the protected
glucose were purchased from Energy-Chemical Company. All the
solvents used in the reaction were purified by re-distillation.
Fig. 1. Reaction temperature-dependent formation of 1-S-alkyl glucosides and 3-S-alkyl glucals. (a) S-ethyl and (b) S-n-dodecyl.
3. Conclusion
4.2. General experimental procedure of Ferrier rearrangement
of 3,4,6-tri-O-acetyl-D-glucal and 3,4-di-O-acetyl-L-rhamnal
Samarium(III) triflate was a highly efficient catalyst for Ferrier
Rearrangement to yield O- and S-2,3-unsaturated glycosides. This
catalyst allowed the reaction proceeding under mild conditions to
give the desired products with good yields and high anomeric se-
lectivities in short time. Under certain conditions, reaction of 3,4-di-
O-acetyl-L-rhamnal with EtSH or n-C12H25SH led to temperature-
dependent formation of C-1-S and C-3-S product. A temperature-
dependent profile of the yield of these two products was given.
catalyzed with Sm(OTf)3
To a stirred solution of 3,4,6-tri-O-acetyl-D-glucal (163 mg,
0.6 mmol) or 3,4-di-O-acetyl-L-rhamnal (128 mg, 0.6 mmol) and
the corresponding alcohol (1.2 equiv) in acetonitrile (5 mL) were
added Sm(OTf)3 (10 mol %) at ambient temperature. The mixture
was stirred under 40 ꢀC for the appropriate amount of time, and the
extent of the reaction was monitored by TLC analysis. The reaction
mixture was diluted with cooled sodium bicarbonate (satd 20 mL)
and extracted with DCM (3ꢁ10 mL). The combined organics were
dried over anhydrous Na2SO4. The solvent was removed under
vacuum. All the products were purified by silica gel column chro-
matography (hexane/EtOAc¼20/1 in the case of 3,4,6-tri-O-acetyl-
4. Experimental
4.1. Method and materials
1H and 13C NMR spectra were recorded on a Bruker AV-400
(400 MHz) spectrometer with Me4Si as internal standard. 19F
NMR spectra were obtained on a Bruker AM-300(282 MHz) spec-
trometer using CFCl3 as an external standard; downfield shifts
D
-glucal as the starting material, or hexane/EtOAc¼60/1 in the case
of 3,4-di-O-acetyl- -rhamnal as the starting material).
L
4.2.1. Ethyl 4,6-di-O-acetyl-2,3-dideoxy-a-D-erythro-hex-2-
being designated as positive, all chemical shifts (
d) were expressed
enopyranoside (3a). Colorless oil; ½a D25
þ106.1 (c 0.98, CHCl3,
ꢂ
in parts per million and coupling constants (J) are in Hertz. Mass
spectra were recorded on a Finnigan-MAT-8430 instrument using
a
:
b
¼33:1){lit5x: ½a D25
ꢂ
þ112.5 (c 1.67, CHCl3,
a:b
¼7:1)}; 1H NMR
(400 MHz, CDCl3):
d
5.91e5.80 (m, 2H), 5.32 (d, J¼9.6 Hz, 1H), 5.05

8508
P. Chen, D. Zhang / Tetrahedron 70 (2014) 8505e8510
(s, 1H), 4.30e4.08 (m, 3H), 3.87e3.79 (m, 1H), 3.62e3.54 (m, 1H),
2.10 (s, 3H), 2.08 (s, 3H), 1.25 (t, J¼7.1 Hz, 3H) ppm; IR (film, cmꢃ1):
2986, 2931, 2842, 1738, 1636, 1504, 1373, 1218, 1095, 1034, 997, 830,
723; MS(ESI) m/z: 280.9([MþNa]þ55), 212.9(100), 152.9(45).
1035, 988, 830, 765, 605; MS (ESI) m/z: 358.9 ([MþNa]þ100),
212.9(95).
4.2.8. 2-Naphthyl 4,6-di-O-acetyl-2,3-dideoxy-a-D-erythro-hex-2-
enopyranoside (3h). White solid; mp¼108e110 ꢀC; ½a D25
þ125.7 (c
ꢂ
4.2.2. Cyclohexyl 4, 6-di-O-acetyl-2,3-dideoxy-
a
-
D
-erythro-hex-2-
0.83, CHCl3,
(400 MHz, CDCl3)
a
only){lit4g: ½a D25
ꢂ
þ151.5 (c 1.0,CHCl3,
a
only)}; 1H NMR
enopyranoside(3b). Colorless oil;
½
a 2D5
þ135.5 (c 1.60, CHCl3,
ꢂ
þ112.9 (c 0.92, CHCl3,
d
8.58 (s, 1H), 7.81 (d, J¼8.0 Hz, 1H), 7.75e7.69 (m,
a
:
b
¼10:1){lit5x: ½a D25
ꢂ
a
:
b
¼10:1)}; 1H NMR
2H), 7.52 (m, 1H), 7.37 (t, J¼7.4 Hz, 1H), 7.14 (t, J¼7.6 Hz, 1H), 6.34 (s,
1H), 6.02 (d, J¼10.3 Hz, 1H), 5.92 (d, J¼10.3 Hz, 1H), 5.69 (d,
J¼8.2 Hz, 1H), 4.44e4.32 (m, 2H), 4.13 (dt, J¼9.1, 2.9 Hz, 1H), 2.19 (s,
3H), 2.17 (s, 3H) ppm; IR (film, cmꢃ1):2945, 2925, 2889, 1742, 1491,
1370, 1242, 1044, 811, 781; MS(ESI) m/z: 378.9([MþNa]þ100).
(400 MHz, CDCl3):
d
5.87e5.79 (m, 2H), 5.28 (d, J¼9.4 Hz, 1H), 5.16
(s, 1H), 4.24e4.15 (m, 3H), 3.63 (s, 1H), 2.08 (s, 3H), 2.07 (s, 3H),
1.98e1.85 (m, 2H), 1.72 (s, 2H), 1.54 (d, J¼10.3 Hz, 1H), 1.42e1.19 (m,
5H) ppm; IR (film, cmꢃ1):2925, 2885, 1744, 1656, 1466, 1371, 1232,
1037, 998, 907, 740, 605; MS (ESI) m/z:335.0 ([MþNa]þ95),
212.8(100).
4.2.9. Ethyl 4-O-acetyl-6-deoxy-2,3-dideoxy-a-D-erythro-hex-2-
enopyranoside (5a). Colorless oil; ½a D25
þ37.23 (c 1.14, CHCl3,
ꢂ
4.2.3.
L
-Menthyl 4,6-di-O-acetyl-2,3-dideoxy-
a
-
D
-erythro-hex-2-
a
:
b
¼9:1) {lit5x: ½a D25
ꢂ
þ21.9 (c 0.67, CHCl3,
a
:b
¼10:1)}; 1H NMR
enopyranoside (3c). Colorless oil; ½a D25
ꢂ
þ140.4 (c 0.54, CHCl3,
(400 MHz, CDCl3):
d
5.95e5.74 (m, 2H), 5.06 (d, J¼10.4 Hz, 1H), 4.98
a
only){lit4i: ½a D25
ꢂ
þ151 (c 1.63, CHCl3,
a
only)}; 1H NMR (400 MHz,
(s, 1H), 3.99 (dq, J¼9.2, 6.2 Hz, 1H), 3.83 (dq, J¼9.6, 7.1 Hz, 1H), 3.56
(m, 1H), 2.09 (s, 3H), 1.30e1.24 (m, 3H), 1.23 (d, J¼3.7 Hz, 3H) ppm;
IR (film, cmꢃ1): 2977, 2933, 2857, 1742, 1449, 1372, 1231, 1029, 910,
772, 604; MS(ESI) m/z: 222.8 ([MþNa]þ50), 212.9(20).
CDCl3):
d
5.90e5.80 (m, 2H), 5.26 (d, J¼8.9 Hz, 1H), 5.08 (s, 1H),
4.23e4.13 (m, 3H), 3.44e3.38 (m, 1H), 2.19 (d, J¼11.7 Hz, 1H), 2.09
(s, 3H), 2.06 (s, 3H), 1.62 (s, 3H), 1.46e0.93 (m, 5H), 0.90 (s, 3H), 0.88
(s, 3H), 0.76 (d, J¼6.9 Hz, 3H) ppm; IR (film, cmꢃ1): 2955, 2924,
2870, 1747, 1454, 1370, 1230, 1102, 1035, 907, 739; MS (ESI) m/z:
391.0 ([MþNa]þ100), 212.9(65).
4.2.10. Cyclohexyl 4-O-acetyl-6-deoxy-2,3-dideoxy-a-D-erythro-hex-
2-enopyranoside (5b). Colorless oil; ½a D25
ꢂ
ꢃ162.35 (c 0.54, CHCl3,
a
only) {lit5x: ½a D25
ꢂ
ꢃ191 (c 0.63, CHCl3,
a
only)}; 1H NMR (400 MHz,
4.2.4. Epiandrosteronyl-4,6-di-O-acetyl-2,3-dideoxy-
a
-
D
-erythro-
CDCl3):
d
5.84e5.72 (m, 2H), 5.08 (s, 1H), 5.02 (d, J¼10.4 Hz, 1H),
hex-2-enopyranoside (3d). White solid; mp¼124e126 ꢀC; ½a D25
ꢂ
4.00 (dq, J¼12.6, 6.3 Hz, 1H), 3.63e3.57 (m, 1H), 2.05 (s, 3H),
1.92e1.84 (m, 2H), 1.76e1.68 (m, 2H), 1.60e1.37 (m, 2H), 1.36e1.27
(m, 2H), 1.27e1.20 (m, 2H), 1.19 (d, J¼6.3 Hz, 3H) ppm; IR (film,
cmꢃ1): 2930, 2859, 1743, 1641, 1448, 1373, 1233, 1099, 1033, 912,
733; MS(ESI) m/z: 272.2([MþNH4]þ100).
þ101.9 (c 0.97, CHCl3,
a
:
b
¼7:1){lit5x: ½a D25
þ112.7 (c 1.81, CHCl3,
ꢂ
a
:b
¼6:1); mp¼125e126 ꢀC}; 1H NMR (400 MHz, CDCl3):
d
5.90e5.81 (m, 2H), 5.30 (d, J¼9.5 Hz, 1H), 5.17 (s, 1H), 4.24e4.15
(m, 3H), 3.63 (m, 1H), 2.43 (dd, J¼19.2, 8.7 Hz, 1H), 2.10 (s, 3H), 2.08
(s, 3H), 1.98e1.70 (m, 7H), 1.57e1.42 (m, 4H), 1.30 (d, J¼27.3 Hz, 6H),
1.15 (t, J¼11.5 Hz, 1H), 1.00e0.93 (m, 2H), 0.86 (s, 3H), 0.83 (s, 3H),
0.71 (d, J¼11.3 Hz, 1H)ppm; IR (film, cmꢃ1): 2931, 2858, 1746, 1648,
1450, 1372, 1222, 1041, 749, 605; MS (ESI) m/z: 520.3
([MþNH4]þ100).
4.2.11. L-Menthyl 4-O-acetyl-6-deoxy-2,3-dideoxy-a-D-erythro-hex-
2-enopyranoside (5c). Colorless oil; ½a D25
ꢂ
ꢃ279.66 (c 0.91, CHCl3,
a
only) {lit5x: ½a D25
ꢂ
ꢃ354 (c 1.15, CHCl3,
a
only)}; 1H NMR (400 MHz,
CDCl3):
d
5.75 (dd, J¼47.2, 10.2 Hz, 2H), 5.12 (s, 1H), 5.00 (d,
J¼8.7 Hz, 1H), 3.96e3.89 (m, 1H), 3.51 (td, J¼10.6, 4.0 Hz, 1H),
2.26e2.23 (m, 1H), 2.06 (s, 3H), 1.65e1.61 (m, 2H), 1.36e1.23 (m,
3H), 1.18 (d, J¼6.2 Hz, 3H), 1.07e0.96 (m, 2H), 0.90 (s, 3H), 0.88 (s,
3H), 0.79 (d, J¼6.9 Hz, 3H), 0.73 (t, J¼6.3 Hz, 1H) ppm; IR (film,
cmꢃ1): 2925, 2866,1745,1453,1374,1233, 1095,1030, 915, 810, 733;
MS(ESI) m/z: 328.2([MþNH4]þ100).
4.2.5. 6-O-(4,6-Di-O-acetyl-2,3-dideoxy-
a
-
D
-erythreo-hex-2-
enopyranosyl)-1,2:3,4-di-O-isopropylidene-a-D-galactopyranose
(3e). White solid; mp¼132e133 ꢀC; ½a D25
ꢂ
þ16.4 (c 0.73, CHCl3,
a:b
¼7:1){lit5x: ½a D25
ꢂ
þ17.6(c 0.83, CHCl3,
a
:
b
¼5:1); mp¼132e134 ꢀC};
1H NMR (400 MHz, CDCl3):
d
5.93e5.86(m, 2H), 5.55(d, J¼5.0 Hz,1H),
5.35 (d, J¼12.9 Hz, 1H), 5.12 (s, 1H), 4.64 (d, J¼6.4 Hz, 1H), 4.35e4.27
(m, 3H), 4.17 (d, J¼11.4 Hz, 2H), 4.02 (d, J¼7.1 Hz,1H), 3.90 (dd, J¼10.2,
6.3 Hz,1H), 3.78 (dd, J¼9.9, 7.4 Hz,1H), 2.14 (s, 3H), 2.11 (s, 3H),1.56 (s,
3H), 1.47 (s, 3H), 1.37 (s, 3H), 1.36 (s, 3H) ppm; IR (film, cmꢃ1): 2994,
2927,1741,1576,1378,1226,1051,1003, 895, 646; MS (ESI) m/z: 490.2
([MþNH4]þ100).
4.2.12. (þ)-endo-Fenacholyl
4-O-acetyl-6-deoxy-2,3-dideoxy-a-D-
erythro-hex-2-enopyranoside (5d). Colorless oil; ½a D25
ꢂ
ꢃ113.68 (c
0.87, CHCl3,
a
:b
¼6:1) {lit5x: ½a D25
ꢂ
ꢃ203 (c 1.56, CHCl3,
a:b
¼17:1)};
1H NMR (400 MHz, CDCl3):
d
5.85e5.79 (m, 2H), 4.98 (d, J¼9.2 Hz,
1H), 4.85 (s, 1H), 3.97e3.90 (m, 1H), 3.18 (s, 1H), 2.05 (s, 3H),
1.69e1.62 (m, 3H), 1.46e1.24 (m, 3H), 1.19 (d, J¼6.3 Hz, 3H), 1.07 (d,
J¼2.5 Hz, 1H), 1.03 (s, 3H), 1.00 (s, 3H), 0.84 (s, 3H) ppm; IR (film,
cmꢃ1): 2965, 2929, 2870, 1746, 1644, 1451, 1371, 1231, 1083, 1049,
884, 761; MS(ESI) m/z: 331.1([MþNa]þ100).
4.2.6. Phenyl 4,6-di-O-acetyl-2,3-dideoxy-a-D-erythro-hex-2-
enopyranoside (3f). White solid; mp¼47e48 ꢀC; ½a D25
ꢂ
þ133.75 (c
¼10:1);
d 7.35e7.31 (m, 2H),
1.05, CHCl3,
a
only){lit:7c
½
a 2D5
ꢂ
þ165.5 (c 1.45, C2H5OH,
a:b
mp¼47e48 ꢀC}; 1H NMR (400 MHz, CDCl3):
7.13 (d, J¼8.0 Hz, 2H), 7.08e7.04 (m, 1H), 6.12e5.96 (m, 2H), 5.73 (s,
1H), 5.41 (d, J¼9.3 Hz, 1H), 4.31 (dd, J¼11.7, 5.6 Hz, 1H), 4.29e4.22
(m, 1H), 4.16 (d, J¼11.7 Hz, 1H), 2.13 (s, 3H), 2.00 (s, 3H) ppm; IR
(film, cmꢃ1):2929, 2853, 1745, 1645, 1447, 1370, 1232, 1051, 975,
792, 604; MS(ESI) m/z: 329.0 ([MþNa]þ65), 212.8(100).
4.2.13. 2,2,2-Tribromomethyl ethoxyl 4-O-acetyl-6-deoxy-2,3-
dideoxy-
ꢃ186 (c 0.72, CHCl3,
a
-
D
-erythro-hex-2-enopyranoside (5e).8 Colorless oil; ½a 2D5
ꢂ
a d 5.82 (d,
only); 1H NMR (400 MHz, CDCl3):
J¼10.2 Hz,1H), 5.73 (d, J¼10.2 Hz,1H), 5.00 (d, J¼9.3 Hz,1H), 4.92 (s,
1H), 3.88 (m, 2H), 3.49 (s, 6H), 3.42e3.40 (m, 1H), 2.04 (s, 3H), 1.19
(d, J¼6.2 Hz, 3H) ppm; 13C NMR (101 MHz, CDCl3):
d 170.15, 130.20,
4.2.7. p-Methoxyphenyl
4,6-di-O-acetyl-2,3-dideoxy-a-
D
-erythro-
127.07, 94.24, 70.56, 66.83, 65.23, 43.39, 34.60, 21.09, 17.91; IR (film,
cmꢃ1): 2975, 2925, 2889,1742,1424,1373,1234,1042, 994, 917, 852,
735, 670, 610; MS (ESI) m/z: 439.9([MþNH4]þ30); HR-ESI:
hex-2-enopyranoside (3g). White solid; mp¼69e70 ꢀC; ½a D25
ꢂ
þ113.5
(c 1.45, CHCl3,
a
only){lit:7c
½
a 2D5
ꢂ
þ123 (c 1.5, CHCl3,
a
:
b
¼15:1);
mp¼69e70 ꢀC}; 1H NMR (400 MHz, CDCl3):
d
7.07 (d, J¼9.1 Hz, 2H),
C
13H23O4NBr3 [MþNH4]þ Calcd 493.9164, found 493.9172.
6.86 (d, J¼9.1 Hz, 2H), 6.06e6.00 (m, 2H), 5.59 (s, 1H), 5.40 (d,
J¼9.3 Hz, 1H), 4.31e4.17 (m, 3H), 3.80 (s, 3H), 2.14 (s, 3H), 2.05 (s,
3H) ppm; IR (film, cmꢃ1):2941, 2841, 1746, 1507, 1450, 1374, 1226,
4.2.14. Phenyl 4-O-acetyl-6-deoxy-2,3-dideoxy-
a
-
D
-erythro-hex-2-
enopyranoside (5f). Yellow oil; ½a D25
ꢂ
ꢃ174 (c 0.65, CHCl3, only);
a

P. Chen, D. Zhang / Tetrahedron 70 (2014) 8505e8510
8509
1H NMR (400 MHz, CDCl3):
d
7.35e7.31 (m, 2H), 7.14e7.11 (m, 2H),
648; MS (ESI) m/z: 234.1 ([MþNH4]þ100); HR-ESI: C10H20O3NS
[MþNH4]þ Calcd 234.1156, found 234.1158.
7.05 (t, J¼7.3 Hz, 1H), 6.05e5.97 (m, 2H), 5.69 (s, 1H), 5.18e5.12 (m,
1H), 4.13 (qd, J¼9.4, 6.3 Hz, 1H), 2.14 (s, 3H), 1.25 (d, J¼6.3 Hz, 3H)
ppm; IR (film, cmꢃ1): 2966, 2929, 2870, 1747, 1642, 1453, 1374, 1227,
1144, 1099, 1055, 921, 801, 760; MS(ESI) m/z: 266.1 ([MþNH4]þ100).
4.2.21. Dodecanyl 4-O-acetyl-6-deoxy-2,3-dideoxy-
a
-
-erythro-1-
thio-hex-2- enopyranoside (7e). Colorless oil; ½a D25
ꢂ
Dꢃ126.72 (c
1.04, CHCl3,
a
:b
¼10:1); 1H NMR (400 MHz, CDCl3):
d 5.96e5.89 (m,
4.2.15. p-Methoxyphenyl
4-O-acetyl-6-deoxy-2,3-dideoxy-
a-D
-er-
1H), 5.75 (d, J¼10.1 Hz, 1H), 5.50 (s, 1H), 5.13 (dd, J¼8.9, 1.7 Hz, 1H),
4.16 (dq, J¼12.6, 6.2 Hz, 1H), 2.78e2.59 (m, 2H), 2.11 (s, 3H),
1.80e1.51 (m, 3H), 1.40e1.26 (m, 20H), 0.90 (t, J¼6.7 Hz, 3H) ppm;
ythro-hex-2-enopyranoside (5g).8 White solid; mp¼112e114 ꢀC;
½
a 2D5
ꢂ
ꢃ151 (c 1.5, CHCl3,
a d 7.06
only); 1H NMR (400 MHz, CDCl3):
(d, J¼9.0 Hz, 2H), 6.86 (d, J¼9.0 Hz, 2H), 6.04e5.95 (m, 2H), 5.55 (s,
1H), 5.14 (d, J¼9.3 Hz, 1H), 4.14 (qd, J¼12.5, 6.2 Hz, 1H), 3.80 (s, 3H),
2.13 (s, 3H), 1.25 (d, J¼6.3 Hz, 3H) ppm; IR (film, cmꢃ1): 2955, 2929,
2873, 1743, 1640, 1458, 1373, 1235, 1106, 1035, 917, 740; MS(ESI) m/
z: 296.1 ([MþNH4]þ100).
13C NMR (101 MHz, CDCl3):
d 129.25, 127.10, 80.25, 70.86, 64.85,
32.16, 31.92, 30.13, 29.76, 29.13, 28.83, 22.70, 21.13, 18.00, 14.13; IR
(film, cmꢃ1): 2925, 2865, 1744, 1637, 1572, 1417, 1371, 1233, 1043,
911, 784; MS (ESI) m/z: 374.3 ([MþNH4]þ100); HR-ESI: C20H40O3NS
[MþNH4]þ Calcd 374.2718, found 374.2723.
4.2.16. Ethyl 4,6-di-O-acetyl-2,3-dideoxy-a-
D
-erythro-1-thio-hex-2-
only)
5.88 (dd, J¼10.1, 4.9 Hz,
4.2.22. Ethyl
4-O-acetyl-6-deoxy-2,3-dideoxy-
a
-
D
-erythro-3-thio-
enopyranoside (7a). Yellow oil; ½a D25
ꢂ
þ132.1 (c 0.68, CHCl3,
a
hex-2-enopyranoside (8d). Colorless oil:½a D25
ꢂ
þ58.5 (c 1.1, CHCl3);
{lit5g
:
a
:b
¼7:1}; 1H NMR (400 MHz, CDCl3)
d
1H NMR (400 MHz, CDCl3):
d
6.39 (dd, J¼6.0, 2.1 Hz, 1H, H-1), 4.95
1H), 5.72 (d, J¼10.2 Hz, 1H), 5.53 (s, 1H), 5.30 (dd, J¼9.2, 1.8 Hz,
1H),4.29e4.24 (m, 1H), 4.21 (dd, J¼11.9, 5.4 Hz, 1H), 4.11 (dd, J¼11.8,
1.9 Hz, 1H), 2.72e2.56 (m, 2H), 2.03 (s, 6H), 1.26 (t, J¼7.4 Hz, 3H)
ppm; IR (film, cmꢃ1):2978, 2931, 2873, 1744, 1664, 1448, 1374, 1236,
1105, 1055, 917, 727, 609; MS(ESI) m/z: 296.9 ([MþNa]þ80),
212.9(100).
(t, J¼8.3 Hz, 1H, H-4), 4.75 (dd, J¼6.0, 2.5 Hz, 1H, H-2), 3.92 (dq,
J¼12.9, 6.4 Hz, 1H, H-5), 3.34 (dt, J¼8.0, 2.3 Hz, 1H, H-3), 2.62e2.48
(m, 2H, eCH2e), 2.13 (s, 3H, eCOCH3), 1.29 (d, J¼6.4 Hz, 3H,
C5eCH3),1.22 (t, J¼7.5 Hz, 3H, eCH2eCH3) ppm; 13C NMR (101 MHz,
CDCl3):
d 170.01, 144.45, 102.04, 73.73, 72.47, 42.51, 22.91, 20.96,
17.28, 14.64; IR (film, cmꢃ1): 2977, 2929, 2891, 1742, 1648, 1426,
1366, 1231, 1033, 993, 910, 728, 610; MS (ESI) m/z: 234.1
([MþNH4]þ50); HR-ESI: C10H20O3NS [MþNH4]þ Calcd 7234.1156,
found 234.1158.
4.2.17. Dodecanyl 4,6-di-O-acetyl-2,3-dideoxy-a-D-erythro-1-thio-
hex-2-enopyranoside (7b). Yellowish oil; ½a D25
þ66 (c 0.62, CHCl3,
ꢂ
a
only){lit5g
:
a:b
¼9:1}; 1H NMR (400 MHz, CDCl3):
d 5.96 (d,
J¼10.2 Hz, 1H), 5.79 (d, J¼10.1 Hz, 1H), 5.57 (s, 1H), 5.39 (dd, J¼9.1,
1.8 Hz,1H), 4.37e4.27 (m, 2H), 4.18 (d, J¼10.1 Hz,1H), 2.79e2.70 (m,
1H), 2.69e2.59 (m, 1H), 2.12 (s, 3H), 2.11 (s, 3H), 1.70e1.62 (m, 3H),
1.40e1.27 (m, 17H), 0.90 (t, J¼6.8 Hz, 3H) ppm; IR (film, cmꢃ1):
2925, 2856, 1747, 1638, 1570, 1453, 1372, 1232, 1049, 959, 788, 605;
MS(ESI)m/z: 432.3 ([MþNH4]þ100).
4.2.23. Dodecanyl 4-O-acetyl-6-deoxy-2,3-dideoxy-
a
-
D
-erythro-3-
thio-hex-2-enopyranoside (8e). Colorless oil: ½a D25
ꢂ
þ81.6 (c 1.32,
CHCl3); 1H NMR (400 MHz, CDCl3):
d
6.42 (dd, J¼6.0, 2.0 Hz, 1H, H-
1), 4.97 (t, J¼8.3 Hz, 1H, H-4), 4.77 (dd, J¼6.0, 2.5 Hz, 1H, H-2), 3.95
(dq, J¼13.0, 6.4 Hz, 1H, H-5), 3.36 (dt, J¼7.9, 2.2 Hz, 1H, H-3), 2.55
(dd, J¼16.3, 7.5 Hz, 2H, eSCH2e), 2.15 (s, 3H, eCOCH3), 1.59 (d,
J¼5.7 Hz, 3H, C5eCH3), 1.33e1.28 (m, 20H, 10-CH2e), 0.90 (s, 3H,
4.2.18. Cyclohexyl 4,6-di-O-acetyl-2,3-dideoxy-
a
-
D
-erythro-hex-2-
eCH2eCH3) ppm; 13C NMR (101 MHz, CDCl3):
d 170.02, 144.50,
eno-1-thio-
a
-
D
-pyranoside (7c). Colorless oil:½a D25
ꢂ
þ90.15 (c 0.9,
102.11, 73.77, 72.50, 42.61, 31.92, 29.45, 28.89, 22.68, 20.98, 17.30,
14.11; IR (film, cmꢃ1): 2925, 2846, 1745, 1633,1574, 1416,1223,1097,
1007, 914, 815, 649; MS (ESI) m/z: 374.3 ([MþNH4]þ100); HR-ESI:
CHCl3,
a
only) {lit5x: ½a D25
ꢂ
þ101.3 (c 1.0,CHCl3,
a
:
b
¼7:1)}; 1H NMR
(400 MHz, CDCl3):
d
5.92 (d, J¼11.2 Hz, 1H), 5.75 (d, J¼10.1 Hz, 1H),
5.65 (s, 1H), 5.34 (d, J¼11.1 Hz, 1H), 4.36e4.14 (m, 3H), 2.93e2.85
(m, 1H), 2.09 (s, 3H), 2.08 (s, 3H), 2.03 (d, J¼16.4 Hz, 2H), 1.76 (d,
J¼15.8 Hz, 2H), 1.60 (d, J¼10.5 Hz, 1H), 1.46e1.29 (m, 5H) ppm; IR
(film, cmꢃ1): 2932, 2874, 1738, 1652, 1447, 1373, 1236, 1050, 965,
833, 738, 608; MS (ESI) m/z:350.9 ([MþNa]þ85), 212.9 (100).
C
20H40O3NS [MþNH4]þ Calcd 374.2720, found 374.2723.
Acknowledgements
This work is financially supported by a grant of The National
Natural Science Foundation of China (NSFC, Grant No. 21272305),
The Natural Science Foundation of Shanghai Municipality (Grant
No. 12ZR1400200) and The Fundamental Research Funds for the
Central Universities.
4.2.19. Cyclohexyl 4-O-acetyl-6-deoxy-2,3-dideoxy-
a
-
D
-erythro-1-
thio-hex-2-enopyranoside (7f). Colorless oil:½a D25
ꢂ
ꢃ149.54 (c 0.81,
CHCl3,
a
only); 1H NMR (400 MHz, CDCl3):
d
5.91 (dd, J¼12.5, 2.4 Hz,
1H), 5.74 (d, J¼10.1 Hz, 1H), 5.61 (s, 1H), 5.11 (dd, J¼9.0, 1.8 Hz, 1H),
4.18 (dq, J¼12.5, 6.3 Hz, 1H), 2.95e2.86 (m, 1H), 2.10 (s, 3H), 2.03 (d,
J¼13.7 Hz, 2H), 1.77 (d, J¼11.0 Hz, 2H), 1.66e1.60 (m, 1H), 1.36 (m,
5H), 1.24 (d, J¼6.3 Hz, 3H) ppm; 13C NMR (101 MHz, CDCl3):
Supplementary data
Supplementary data related to this article can be found at http://
dx.doi.org/10.1016/j.tet.2014.09.060.
d
170.56, 129.45, 126.98, 79.18, 70.85, 64.76, 44.56, 34.37, 34.00,
26.05, 25.72, 21.12, 18.00; IR (film, cmꢃ1): 2927, 2854, 1742, 1638,
1572, 1415, 1374, 1232, 1092, 1048, 786, 646; MS (ESI) m/z: 288.2
([MþNH4]þ100); HR-ESI: C14H26O3NS [MþNH4]þ Calcd 288.1625,
found 288.1628.
References and notes
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4.2.20. Ethyl
4-O-acetyl-6-deoxy-2,3-dideoxy-
a-D
-erythro-1-thio-
hex-2-enopyranoside (7d). Colorless oil; ½a D25
ꢂ
þ15.33 (c 0.47, CHCl3,
a
:
b
¼14:1); 1H NMR (400 MHz, CDCl3):
5.90 (d, J¼10.1 Hz,1H), 5.74
d
(d, J¼10.1 Hz, 1H), 5.51 (s, 1H), 5.10 (dd, J¼8.9, 1.5 Hz, 1H), 4.14 (dq,
J¼12.6, 6.2 Hz, 1H), 2.79e2.59 (m, 2H), 2.09 (s, 3H), 1.31 (t, J¼7.4 Hz,
3H), 1.23 (d, J¼6.2 Hz, 3H) ppm; 13C NMR (101 MHz, CDCl3):
d
170.51, 129.17, 127.18, 79.82, 70.81, 64.83, 26.03, 21.10, 17.97, 15.37;
IR (film, cmꢃ1): 2924, 2846, 1743, 1637, 1574, 1414, 1109, 1010, 923,

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P. Chen, D. Zhang / Tetrahedron 70 (2014) 8505e8510
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