Transition-Metal-Free Approach to Polysubstituted Furans

Article abstract of DOI:10.1021/acs.joc.9b03006

A convenient and straightforward strategy for the synthesis of 2,3-disubstituted and 2,3,5-trisubstituted furans via a base-promoted domino reaction of β-keto compounds with vinyl dichlorides is described. This transition-metal-free approach proceeds under operationally simple reaction conditions featuring easily available starting materials, a broad substrate scope, and good functional group tolerance.

Full text of DOI:10.1021/acs.joc.9b03006

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Transition-Metal-Free Approach to Polysubstituted Furans
Changming You, Zhenming Zhang, Yongliang Tu, Hong Tang, Yuanfeng Wang, Da Long, and Junfeng Zhao
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.9b03006 • Publication Date (Web): 16 Jan 2020
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Page 1 of 9
The Journal of Organic Chemistry
Transition-Metal-Free Approach to Polysubstituted Furans
1
2
3
4
5
6
7
8
Changming You,† Zhenming Zhang,† Yongliang Tu,† Hong Tang,† Yuanfeng Wang,† Da Long,†
Junfeng Zhao*†‡
†College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, Jiangxi, P. R. China
‡School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, 511436, Guangdong, P. R. China
zhaojf@jxnu.edu.cn
Supporting Information
9
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60
R1
O
R2
ABSTRACT: A convenient and straightforward strategy for the
synthesis of 2,3-disubstituted and 2,3,5-trisubstituted furans via a
base-promoted domino reaction of β-keto compounds with vinyl
dichlorides is described. This transition-metal free approach proceeds
under operationally simple reaction conditions featured with easily
available starting materials, broad substrate scope and good functional
group tolerance.
Cl
Cl
O
Cs2CO3, DMSO
N2, 120 °C
+
EWG
R1
R2
EWG
57 examples
53~85% yields
EWG = COR, CO2R, CN, SO2R
R2 = H, aryl, alkyl
1) Transition-metal catalyzed reactions of 1,3-dicarbonyls with alkynes
Furan skeleton is not only an important class of five-
membered oxygen-containing heterocycles which are widely
distributed in numerous bioactive compounds and natural
products,1 but also a useful synthetic intermediate in organic
synthesis.2 As a consequence, a plethora of methods have been
developed for furan synthesis.3 Among them, besides the
classical Feist−Bénary reaction,4 intramolecular cyclization of
ynenones5 or its analogues6 have received considerable
attentions as a powerful strategy for the synthesis of
polysubstituted furans in the past decades.7 Recently, readily
available 1,3-dicarbonyl compounds, which react with the
corresponding alkyne partner to produce the ynenones in situ,
are employed as substrates for the synthesis of furan
derivatives with the assistance of transition-metal catalyst
(Scheme 1, eq 1).8 For example, Jiang and co-workers
reported an effective method to construct the furan rings via a
copper catalyzed oxidative cyclization of 1,3-dicarbonyl
compounds with alkyne derivatives.9 Lei’s group developed a
C−H/C−H oxidative-coupling/cycloisomerization of 1,3-
dicarbonyl compounds with terminal alkynes to synthesize
trisubstituted furans.10 In addition, polysubstituted alkenes
could also react with 1,3-dicarbonyl compounds to afford
furan derivatives via transition-metal catalysis (Scheme 1, eq
2).11 For instance, cross-dehydrogenative-coupling tandem
O
O
O
Transition-metal
R2
R3
R3
+
R1
R2
O
R1
2) Transition-metal catalyzed reactions of 1,3-dicarbonyls with alkenes
O
R'''/R''
R'
R'''
R''
O
O
Transition-metal
R2
+
R1
R2
R'
O
R1
3) Base-promoted reaction of -keto compounds with 1,1-dichloroalkenes

Cl
O
EWG
R1
Base
R2
+
EWG
R1
R2
Cl
This Work
O
EWG = COR, CO2R, CN, SO2R
R2 = H, aryl, alkyl
Scheme 1. Synthetic Strategies for Polysubstituted Furans
under basic reaction conditions, in which alkynyl chloride
proved to be the key intermediate formed in situ from 1,1-
dichloroalkenes.18 We thus hypothesized that 1,1-
dichloroalkylene would be an ideal C2-building block for the
synthesis of ploysubstituted furans.19 Herein, we reported a
base-promoted synthesis of 2,3-disubstituted and 2,3,-
trisubstituted furans by employing readily available and cheap
β-keto compounds and 1,1-dichloroalkenes as the starting
materials (Scheme 1, eq 3).
Initially, 1,3-diphenylpropane-1,3-dione 1a and 1,1-di-
chloroethylene 2a were used as the model substrates to
optimize the reaction conditions (Table 1). To our delight, the
target furan product 3a could be obtained in 56% yield by
using 2.0 equiv of NaH as the base with DMF as the solvent
(Table 1, entry 1). Further screening of the base revealed that
Cs2CO3 was the optimal choice for this transformation (entries
2−6). DMSO was found to be the best solvent to give the
desired product 3a in 76% yield (entries 7−11). Increasing the
reaction of
functionalized alkenes with 1,3-dicarbonyl
compounds was an effective synthetic approach to construct
ploysubstituted furans using palladium12 or iron catalyst13.
However, these elegant strategies, in some cases, suffered
from limitations such as harsh reaction conditions and narrow
substrate scope. Furthermore, the use of transition-metal
catalyst is another shortcoming because transition-metal free
processes are favorable in pharmaceutical synthesis (especially
in the last few steps) due to the concerns of transition-metal
residues. Therefore, a general and practical transition-metal
free approach to ploysubstituted furans with easily available
raw materials under mild reaction conditions is always
desirable.14
1,1-Dihaloalkenes are useful synthetic intermediates in
organic chemistry and material science.15 Compared to the
extensive study on 1,1-dibromoalkenes,16 the transformations
of less reactive 1,1-dichloroalkenes have received little
attention due to the poor reactivity of C−Cl bond in transition-
metal catalyzed reaction.17 Very recently, our group reported
that 1,1-dichloroalkenes could be used to synthesize ynamides
o
reaction temperature to 120 C afforded the product in higher
yields. However, further increase of reaction temperature
resulted a lower yield (entries 12−14). Finally, the amount of
Cs2CO3 was examined and 2.5 equiv of Cs2CO3 proved to be
the best choice to afford the target furan in 86% yield (entries
15−17).
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Table 1. Optimization of the Reaction Conditionsa
products in good yields. Substrates 3-aryl β-ketoesters bearing
O
1
2
3
4
5
6
7
8
both electron-donating groups (4-Me, 3-Me, 2-Me, and 4-
OMe) and electron-withdrawing groups (4-F, 4-Cl, 4-Br, 4-
NO2, and 4-CN) on the phenyl ring were well-tolerated
(3e−n). The structure of 3n was further confirmed by X-ray
crystallography (see the Supporting Information for details).
Moreover, β-ketoesters containing pyridine-4-yl, furan-2-yl, 2-
thiophen-2-yl and tert-butyl groups could react smoothly to
afford the corresponding products (3o-r) in good to high
yields. Furthermore, β-ketosulfonyl compounds bearing
functionalized phenyl, nathphyl, benzofuranyl, and methyl
groups (3s−y) and β-ketonitriles bearing thiophenyl and
substituted phenyl groups (3z, 3aa−ad) were also effective
substrates, providing the corresponding furan derivatives in
good to high yields.
Cl
O
O
base
+
Ph
Ph
Ph
Cl
O
Ph
1a
2a
3a
entry
1
2
3
4
Base
NaH
Solvent
DMF
DMF
DMF
DMF
Temp (oC)
80
Yield (%)b
56
35
0
0
31
tBuOK
K2CO3
Et3N
80
80
80
5
6
7
8
EtONa
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
DMF
DMF
THF
80
80
80
80
80
80
80
100
120
140
120
120
120
9
69
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
trace
38
trace
trace
76
PhMe
dioxane
MeCN
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
9
10
11
12
13
14
15c
16d
17e
79
82
65
50
86
86
Scheme 3. Scope of β-Keto Compounds for the Synthesis of
Trisubstituted Furansa
EWG
Cl
Cl
O
Cs2CO3, DMSO
N2, 120 °C
+
Ph
EWG
R1
R1
O
Ph
1
4a
5
a
Reaction condition: 1a (0.2 mmol), 2a (0.4 mmol), and base (2.0
b
c
O
O
equiv) in solvent (1.0 mL) for 2 h under N2. Isolated yield. Cs2CO3
(1.0 equiv) was used. Cs2CO3 (2.5 equiv) was used. Cs2CO3 (3.0
equiv) was used.
O
O
d
e
Ph
OEt
Ph
Ph
Ph
Ph
Ph
O
O
O
O
b
5b
, 62%
5c
, 70%
5d
, 74%
5a
, 83% (72% )
With the optimized reaction conditions in hand, we next
surveyed the substrate scope of β-keto compounds 1 including
β-diketones, β-ketoesters, β-ketosulfonyls, and β-ketonitriles
for the synthesis of 2,3-disubstituted furans. As shown in
Scheme 2, β-diketones compounds such as 1-phenylbutane-
1,3-dione (3b), cyclohexane-1,3-dione (3c) and 1-(diethylam-
ino)propan-2-one (3d) were suitable partners for 1,1-
dichloroethylene to afford the desired disubstituted furan
O
O
O
O
OEt
OEt
OEt
OEt
Ph
Ph
Ph
Ph
O
O
O
O
F
Cl
Br
5e
, 62%
5f
5g
, 54%
5h
, 53%
, 58%
O
O
S
Ph
O
CN
CN
OEt
N
Ph
Ph
Ph
Ph
Ph
O
O
S
O
O
Scheme 2. Scope of β-Keto Compounds for the Synthesis of
5i
, 61%
5j
5k
, 61%
5l
, 78%
, 60%
Disubstituted Furansa
CN
CN
Cl
Cl
EWG
CN
O
Cs2CO3, DMSO
N2, 120 °C
Ph
+
EWG
O
O
Ph
O
R
O
R
tBu
1
2a
3
OMe
Cl
5m
, 73%
5n
, 63%
5o
, 70%
O
O
O
O
aReaction conditions: 1 (0.2 mmol), 4a (0.4 mmol), Cs2CO3 (2.5
equiv) in DMSO (1.0 mL) at 120 oC under N2 for 10 h. Isolated yield.
b10 mmol scale of 1a.
Ph
Ph
Me
O
O
O
O
Ph
Me
, 60%
NEt2
b
3a
3b
3c
3d
, 65%
, 86% (65% )
, 65%
3e
, R = 4-H, 63%
O
O
3f
, R = 4-Me, 62%
3g
3h
3i
3j
, R = 3-Me, 70%
, R = 2-Me, 64%
, R = 4-OMe, 55%
, R = 4-F, 65%
Subsequently, we turned our attention to define the capacity
of this method for the synthesis of 2,3,5-trisubstituted furans
(Scheme 3). When (2,2-dichlorovinyl)benzene reacted with 1-
phenylbutane-1,3-dione under the above reaction conditions,
2,3,5-trisubstituted furans 5a could be obtained in 83% yield
with a prolonged reaction time. It is noteworthy that product
5a could be obtained in 72% yield for a 10 mmol scale
reaction. 1-Phenylbutane-1,3-dione and cyclohexane-1,3-dione
worked well to furnish the corresponding products 5b and 5c
in 62% and 70% yields, respectively. Furthermore, a broad
range of β-ketoesters bearing diverse functional aryl groups
reacted smoothly with 4a to give the corresponding furan
products (5a−i) in good yields. When 1-phenyl-2-
(phenylsulfonyl)ethanone was tested as a substrate, the target
product (5j) could be obtained in 60% yield. Moreover, a
variety of β-ketonitriles bearing thiophenyl, Ph, 4−MeOPh,
OEt
OEt
O
O
R
3k
3l
, R = 4-Cl, 67%
, R = 4-Br, 72%
CN
Ph
3n
3n
, 71%
3m
, R = 4-NO2, 72%
3s
3t
3u
3v
3w
, R = Ph, 80%
, R = 4-OMePh, 82%
, R = 4-ClPh, 76%
, R = 4-CNPh, 70%
, R = 2-nathphyl, 79%
, R = Me, 70%
O
O
S
3o,
R = pyridin-4-yl, 83%
, R = furan-2-yl, 60%
3p
3q
OEt
O
, R = thiophen-2-yl, 75%
O
O
t
R
R
3r
, R = Bu, 60%
3x
O
S
Ph
CN
O
CN
3aa
3ab
3ac
3ad
, R = 4-H, 70%
, R = 4-OMe, 85%
, R = 4-Me, 76%
, R = 4-Cl, 60%
O
O
O
S
O
R
3z
, 80%
3y
, 70%
aReaction conditions: 1 (0.2 mmol), 2a (0.4 mmol), Cs2CO3 (2.5
o
equiv) in DMSO (1.0 mL) at 120 C under N2 for 2 h. Isolated yield.
b10 mmol scale of 1a.
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The Journal of Organic Chemistry
Scheme 4. Scope of 1,1-Dichloroalkenes for the Synthesis
On the basis of our experimental results, a plausible reaction
mechanism was proposed in Scheme 5. The key intermediate
alkynyl chloride I would be formed via elimination of 1,1-
dichloroalkene under basic reaction conditions.20 Then,
nucleophilic α-addition of anion intermediate II formed from
deprotonation of β-keto compound to alkynyl chloride I
produced intermediate III,16 which underwent a further
elimination to give the β-ketoalkyne intermediate IV.
Subsequently, intarmolecular cycloisomerization of IV via
intermediate V under basic reaction conditions finally
furnished the expected polysubstituted furans.
of Trisubstituted Furansa
1
2
3
4
5
6
7
8
O
Cl
O
O
Cs2CO3, DMSO
N2, 120 °C
Ph
+
Ph
Ph
R
Ph
Ph
O
R
Cl
O
Ph
1a
4
6
O
O
Me
Me
Ph
Ph
Me
tBu
O
O
O
Ph
Ph
Ph
6a
6b
6e
6h
6k
6c
, 60%
, 60%
, 65%
9
O
O
O
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ph
Ph
MeO
F
■ CONCLUSIONS
O
O
O
Ph
O
Ph
Ph
O
6d
, 70%
6f
6i
6l
, 64%
O
, 78%
In conclusion, we have developed a novel synthetic strategy
for the preparation of polysubstituted furans with cheap and
easily available raw materials in the absence of transition-
metal catalyst. A variety of β-keto compounds including β-
diketones, β-ketoesters, β-ketosulfonyls, and β-ketonitriles as
well as vinyl dichlorides are competent participants in the
base-promoted reaction to afford 2,3-disubstituted and 2,3,5-
trisubstituted furans in moderate to high yields. With attractive
advantages such as transition-metal free, operationally simple
reaction conditions, easily available starting materials, broad
substrate scope and good functional group tolerance, we
believed that this method would find broad application for the
synthesis of various valuable furan-containing complex
molecules in organic chemistry and drug discovery.
Ph
Ph
Ph
Cl
Br
O
O
O
Ph
Ph
Ph
6g
, 71%
, 70%
O
, 60%
O
O
Ph
Ph
Ph
Ph
O
O
O
Ph
Ph
Ph
Ph
Ph
6j
, 72%
, 70%
, 62%
aReaction condition: 1a (0.2 mmol), 4 (0.4 mmol), Cs2CO3 (2.5
o
equiv) in DMSO (1.0 mL) at 120 C under N2 for 10 h. Isolated
yield.
t
4−ClPh, and Bu performed well in the reaction, affording the
target products (5k−o) in 63−78% yields.
■ EXPERIMENTAL SECTION
Next, various vinyl dichlorides with 1,3-diphenylpropane-
1,3-dione 1a were subjected to the above optimized reaction
conditions, furnishing the corresponding products (6a−l). As
shown in Scheme 4, the reactions were performed well in
good yields when aryl 1,1-dichlorides bearing 4-Me, 3-Me, 2-
Me, 4-tBu, and 4-OMe (6a−e) on the phenyl ring were
employed. Notably, halogen-containing compounds (4-F, 4-
Cl, and 4-Br) proceeded smoothly, delivering corresponding
products (6f−h) in high yields. The substrate 2-(2,2-
dichlorovinyl)naphthalene was also reactive to afford the
desired products 6i in 60% yield. It is noteworthy that this
transformation showed favorable compatibility to nonaromatic
groups, such as alkenyl, alkynyl, and alkyl groups, and the
corresponding products (6j−l) were achieved in good yields.
All reactions were performed in oven-dried glassware unless
otherwise noted and monitored by thin-layer chromatography
(TLC). Products purification was done using silica gel column
chromatography. All reagents and solvents were purchased from
commercial vendors and used without further purification.
Starting materials 1,1-dichloroethylene and β-keto compounds
including β-diketones, β-ketoesters, β-ketosulfonyls, and β-
ketonitriles were obtained from commercial suppliers and used
without further purification. Other starting materials vinyl
dichlorides were synthesized following our previous works.18b
1H NMR and 13C NMR spectra were recorded on Brukeravance
400 MHz and Bruker AMX 400 MHz spectrometer at 400 and
1
100 MHz, respectively. H NMR spectra were recorded in CDCl3
and referenced to residual CHCl3 at 7.26 ppm, and 13C NMR
spectra were referenced to the central peak of CDCl3 at 77.0 ppm.
High-resolution mass spectra (HRMS) were obtained by the
electrospray ionization time-of-flight (ESI) mass spectrometry.
Flash column chromatography purification of compounds was
carried out by gradient elution using ethyl acetate (EA) in light
petroleum ether (PE). Multiplicities are reported using the
following abbreviations: s = singlet, d = doublet, t = triplet, q =
quartet, m = multiplet.
Scheme 5. Proposed Reaction Mechanism
O
O
base
EWG
R1
EWG
R1
II
O
Cl
Cl
Cl
R2
base
- HCl
R2
Cl
General Procedure and Characterization Data for Products.
To a dried Schlenk tube was added a mixture of -ketos 1 (0.2
mmol, 1 equiv), 1,1-dichloroethenes 2 or 4 (0.4 mmol, 2 equiv),
Cs2CO3 (0.5 mmol, 2.5 equiv), and DMSO (1.0 mL). The mixture
was stirred at 120 °C (heating mantle) for 2 h or 10 h under a N2
atmosphere. After the reaction was completed, the mixture was
cooled to room temperature. Then the reaction was quenched by
water and extracted with ethyl acetate three times. The combined
organic layers were dried over anhydrous Na2SO4 and evaporated
under vacuum. The desired products were obtained in the
R1
EWG
R2
III
I
- Cl-
R2
R2
O
R2
O
base
O
R1
EWG
R1
R1
EWG
V
EWG
IV
product
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corresponding yields after purification by flash chromatography
on silica gel with petroleum ether/ethyl acetate.
CDCl3) δ 7.83−7.75 (m, 2H), 7.42 (d, J = 1.9 Hz, 1H), 7.33 (t, J =
8.0 Hz, 1H), 7.22 (d, J = 7.6 Hz, 1H), 6.85 (d, J = 2.0 Hz, 1H),
4.31 (q, J = 7.1 Hz, 2H), 2.42 (s, 3H), 1.34 (t, J = 7.1 Hz, 3H);
13C{1H} NMR (100 MHz, CDCl3) δ 163.6, 157.6, 141.1, 137.6,
130.1, 129.7, 129.0, 128.0, 125.7, 113.8, 113.0, 60.5, 21.5, 14.2;
1
2
3
4
5
6
7
8
10 mmol Scale Synthesis of 3a. To a dried Schlenk tube was
added a mixture of -ketos 1a (10.0 mmol, 2.24 g, 1 equiv), 1,1-
dichloroethenes 2a (20.0 mmol, 1.94 g, 2 equiv), Cs2CO3 (25.0
mmol, 8.15 g, 2.5 equiv), and DMSO (5.0 mL). The mixture was
stirred at 120 °C (heating mantle) for 2 h under a N2 atmosphere.
After the reaction was completed, the mixture was cooled to room
temperature. Then the reaction was quenched by water, filtered
and extracted with ethyl acetate (3×30 mL). The combined
organic layers were dried over anhydrous Na2SO4 and evaporated
under vacuum. The crude residue was then purified by column
chromatography on silica gel using a PE/EA (50:1) mixture as
eluent to afford the pure target compounds 3a (1.6 g, yield 65%).
10 mmol Scale Synthesis of 5a. To a dried Schlenk tube was
added a mixture of -ketos 1a (10.0 mmol, 2.24 g, 1 equiv), 1,1-
dichloroethenes 4a (20.0 mmol, 3.46 g, 2 equiv), Cs2CO3 (25.0
mmol, 8.15 g, 2.5 equiv), and DMSO (5.0 mL). The mixture was
stirred at 120 °C (heating mantle) for 10 h under a N2 atmosphere.
After the reaction was completed, the mixture was cooled to room
temperature. Then the reaction was quenched by water, filtered
and extracted with ethyl acetate (3×30 mL). The combined
organic layers were dried over anhydrous Na2SO4 and evaporated
under vacuum. The crude residue was then purified by column
chromatography on silica gel using a PE/EA (50:1) mixture as
eluent to afford the pure target compounds 5a (2.3 g, yield 72%).
Phenyl(2-phenylfuran-3-yl)methanone (3a).8c Yellow liquid
IR (KBr) ν̃
2973, 1718, 1567, 1305, 1074, 709 cm−1; HRMS (ESI)
calcd. for C14H15O3+ [M + H]+: 231.1016, found: 231.1012.
Ethyl 2-(o-tolyl)furan-3-carboxylate (3h). Yellow liquid (29.6
1
mg, yield 64%); Rf = 0.4 (PE/EA = 20:1); H NMR (400 MHz,
CDCl3) δ 7.49 (d, J = 2.0 Hz, 1H), 7.44 (dd, J = 7.6, 1.4 Hz, 1H),
7.38 (td, J = 7.5, 1.5 Hz, 1H), 7.33−7.27 (m, 2H), 6.89 (d, J = 2.0
Hz, 1H), 4.23 (q, J = 7.1 Hz, 2H), 2.30 (s, 3H), 1.22 (t, J = 7.1 Hz,
3H); 13C{1H} NMR (100 MHz, CDCl3) δ 163.3, 158.6, 141.6,
137.9, 130.8, 130.0, 129.9, 129.5, 125.1, 115.4, 111.4, 60.2, 19.9,
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
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41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
14.0; IR (KBr) ν̃
2981, 1718, 1488, 1305, 1074, 749 cm−1; HRMS
(ESI) calcd. for C14H15O3+ [M + H]+: 231.1016, found: 231.1012.
Ethyl 2-(4-methoxyphenyl)furan-3-carboxylate (3i). Yellow
o
solid (27.1 mg, yield 55%); mp = 50−52 C; Rf = 0.4 (PE/EA =
1
20:1); H NMR (400 MHz, CDCl3) δ 7.96 (d, J = 9.0 Hz, 2H),
7.37 (d, J = 2.0 Hz, 1H), 6.95 (d, J = 9.0 Hz, 2H), 6.82 (d, J = 2.0
Hz, 1H), 4.30 (q, J = 7.1 Hz, 2H), 3.85 (s, 3H), 1.34 (t, J = 7.1 Hz,
3H); 13C{1H} NMR (100 MHz, CDCl3) δ 163.7, 160.4, 157.8,
140.5, 129.9, 122.5, 113.5, 112.8, 112.7, 60.4, 55.3, 14.3; IR (KBr)
ν̃
2981, 1710, 1607, 1488, 1074, 837 cm−1; HRMS (ESI) calcd.
for C14H15O4+ [M + H]+: 247.0965, found: 247.0961.
Ethyl 2-(4-fluorophenyl)furan-3-carboxylate (3j). Yellow liquid
1
(30.4 mg, yield 65%); Rf = 0.4 (PE/EA = 20:1); H NMR (400
1
MHz, CDCl3) δ 8.08−7.90 (m, 2H), 7.40 (d, J = 2.0 Hz, 1H), 7.11
(t, J = 8.8 Hz, 2H), 6.84 (d, J = 2.0 Hz, 1H), 4.30 (q, J = 7.1 Hz,
2H), 1.34 (t, J = 7.1 Hz, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ
163.5, 163.3 (JC-F = 250.0 Hz), 156.6, 141.1, 130.5 (JC-F = 8.8 Hz),
126.0 (JC-F =3.4 Hz), 115.1 (JC-F =22.2 Hz), 113.7, 113.0, 60.6,
(42.7 mg, yield 86%); Rf = 0.5 (PE/EA = 20:1); H NMR (400
MHz, CDCl3) δ 7.83 (d, J = 8.2, 1.4 Hz, 2H), 7.75−7.65 (m, 2H),
7.55−7.45 (m, 2H), 7.37 (t, J = 7.7 Hz, 2H), 7.33−7.25 (m, 3H),
6.69 (d, J = 1.9 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ
191.8, 156.0, 141.3, 138.1, 132.9, 132.8, 129.8, 129.7, 129.0,
128.3, 127.5, 120.9, 113.8.
14.2; IR (KBr) ν̃
2981, 1710, 1496, 1281, 1074, 749 cm−1; HRMS
(ESI) calcd. for C13H12FO3+ [M + H]+: 235.0765, found: 235.0769.
(2-Methylfuran-3-yl)(phenyl)methanone (3b).8c Yellow liquid
1
Ethyl 2-(4-chlorophenyl)furan-3-carboxylate (3k). Yellow solid
(22.3 mg, yield 60%); Rf = 0.5 (PE/EA = 20:1); H NMR (400
o
(33.5 mg, yield 67%); mp = 50−52 C; Rf = 0.4 (PE/EA = 20:1);
MHz, CDCl3) δ 7.80 (d, J = 7.5 Hz, 2H), 7.56 (t, J = 7.4 Hz, 1H),
7.47 (t, J = 7.6 Hz, 2H), 7.29 (d, J = 2.0 Hz, 1H), 6.58 (d, J = 2.0
Hz, 1H), 2.54 (s, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ 191.3,
159.5, 140.1, 139.1, 132.2, 129.0, 128.3, 120.4, 111.9, 14.2.
6,7-Dihydrobenzofuran-4(5H)-one (3c).21 white solid (17.7 mg,
yield 65%); Rf = 0.6 (PE/EA = 4:1); 1H NMR (400 MHz, CDCl3)
δ 7.32 (s, 1H), 6.67 (d, J = 1.7 Hz, 1H), 2.88 (t, J = 6.3 Hz, 2H),
2.50 (t, J = 6.3 Hz, 2H), 2.30−2.10 (m, 2H); 13C{1H} NMR (100
MHz, CDCl3) δ 194.5, 167.1, 142.6, 121.1, 106.5, 37.7, 23.3, 22.6.
Methyl 2-(diethylamino)furan-3-carboxylate (3d). Brown liquid
1H NMR (400 MHz, CDCl3) δ 7.96 (d, J = 8.7 Hz, 2H), 7.50−7.25
(m, 3H), 6.84 (d, J = 2.0 Hz, 1H), 4.30 (q, J = 7.1 Hz, 2H), 1.34 (t,
J = 7.2 Hz, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ 163.4, 156.2,
141.3, 135.3, 129.6, 128.3, 128.2, 114.3, 113.1, 60.6, 14.2; IR
(KBr) ν̃
2981, 1710, 1281, 1186, 1011, 749 cm−1; HRMS (ESI)
calcd. for C13H12ClO3+ [M + H]+: 251.0469, found: 251.0473.
Ethyl 2-(4-bromophenyl)furan-3-carboxylate (3l).24 Yellow
1
solid (42.3 mg, yield 72%); Rf = 0.4 (PE/EA = 20:1); H NMR
(400 MHz, CDCl3) δ 7.80 (d, J = 8.7 Hz, 2H), 7.46 (d, J = 8.7 Hz,
2H), 7.32 (d, J = 2.0 Hz, 1H), 6.75 (d, J = 2.0 Hz, 1H), 4.21 (q, J
= 7.2 Hz, 2H), 1.25 (t, J = 7.2 Hz, 3H); 13C{1H} NMR (100 MHz,
CDCl3) δ 163.4, 156.2, 141.4, 131.3, 129.8, 128.7, 123.6, 114.4,
113.2, 60.7, 14.3.
1
(23.5 mg, yield 65%); Rf = 0.5 (PE/EA = 4:1); H NMR (400
MHz, CDCl3) δ 7.19 (d, J = 1.9 Hz, 1H), 6.29 (d, J = 1.9 Hz, 1H),
3.39 (s, 4H), 2.32 (s, 3H), 1.13 (t, J = 7.2 Hz, 6H); 13C{1H} NMR
(100 MHz, CDCl3) δ 165.9, 152.7, 140.0, 116.5, 109.6, 42.8, 39.3,
Ethyl 2-(4-nitrophenyl)furan-3-carboxylate (3m). white solid
14.2, 13.1, 12.7; IR (KBr) ν̃ 2981, 1639, 1449, 1210, 1099, 741
o
+
cm−1; HRMS (ESI) calcd. for C10H16NO2 [M + H]+: 182.1176,
(37.6 mg, yield 72%); mp = 64−66 C; Rf = 0.3 (PE/EA = 20:1);
1H NMR (400 MHz, CDCl3) δ 8.25−8.20 (m, 4H), 7.50 (d, J = 1.6
Hz, 1H), 6.89 (d, J = 1.8 Hz, 1H), 4.32 (q, J = 7.1 Hz, 2H), 1.35 (t,
J = 7.1 Hz, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ 163.0,
154.3, 147.6, 142.6, 135.4, 128.8, 123.3, 116.7, 113.8, 61.0, 14.2;
found: 182.1172.
Ethyl 2-phenylfuran-3-carboxylate (3e).22 Yellow liquid (27.2
1
mg, yield 63%); Rf = 0.5 (PE/EA = 20:1); H NMR (400 MHz,
CDCl3) δ 8.10−7.64 (m, 2H), 7.48−7.15 (m, 4H), 6.75 (d, J = 2.0
Hz, 1H), 4.21 (q, J = 7.1 Hz, 2H), 1.24 (t, J = 7.1 Hz, 3H);
13C{1H} NMR (100 MHz, CDCl3) δ 163.6, 157.5, 141.2, 129.8,
129.3, 128.4, 128.1, 113.9, 113.0, 60.5, 14.2.
IR (KBr) ν
̃
2988, 1718, 1512, 1297, 1074, 757 cm−1; HRMS (ESI)
calcd. for C13H11NNaO5 [M + Na]+: 284.0529, found: 284.0537.
Ethyl 2-(4-cyanophenyl)furan-3-carboxylate (3n). white solid
(34.2 mg, yield 71%); mp = 160−162 oC; Rf = 0.3 (PE/EA = 20:1);
1H NMR (400 MHz, CDCl3) δ 8.49−8.02 (m, 2H), 7.69 (dd, J =
8.6, 1.8 Hz, 2H), 7.49 (d, J = 1.9 Hz, 1H), 6.88 (d, J = 1.9 Hz, 1H),
4.31 (qd, J = 7.1, 1.8 Hz, 2H), 1.35 (td, J = 7.2, 1.8 Hz, 3H);
13C{1H} NMR (100 MHz, CDCl3) δ 163.1, 154.7, 142.4, 133.7,
+
Ethyl 2-(p-tolyl)furan-3-carboxylate (3f).23 Yellow liquid (28.5
1
mg, yield 62%); Rf = 0.5 (PE/EA = 20:1); H NMR (400 MHz,
CDCl3) δ 7.88 (d, J = 8.2 Hz, 2H), 7.40 (d, J = 2.0 Hz, 1H), 7.24
(d, J = 8.1 Hz, 2H), 6.83 (d, J = 1.9 Hz, 1H), 4.30 (q, J = 7.1 Hz,
2H), 2.40 (s, 3H), 1.34 (t, J = 7.1 Hz, 3H); 13C{1H} NMR (100
MHz, CDCl3) δ 163.6, 157.8, 140.8, 139.4, 128.8, 128.3, 127.0,
113.4, 112.9, 60.4, 21.4, 14.3.
131.9, 128.5, 118.6, 116.2, 113.6, 112.4, 60.9, 14.2; IR (KBr) ν
̃
2988, 1710, 1479, 1297, 1074, 741 cm−1; HRMS (ESI) calcd. for
C14H12NO3+ [M + H]+: 242.0812, found: 242.0815.
Ethyl 2-(m-tolyl)furan-3-carboxylate (3g). Yellow liquid (32.3
1
mg, yield 70%); Rf = 0.4 (PE/EA = 20:1); H NMR (400 MHz,
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The Journal of Organic Chemistry
Ethyl 2-(pyridin-4-yl)furan-3-carboxylate (3o). white solid
2-(Naphthalen-2-yl)-3-(phenylsulfonyl)furan (3w). Yellow solid
(52.8 mg, yield 79%); mp = 114−116 oC; Rf = 0.3 (PE/EA = 10:1);
1H NMR (400 MHz, CDCl3) δ 8.43 (d, J = 1.7 Hz, 1H), 7.92 (dd,
J = 8.7, 1.9 Hz, 2H), 7.88−7.80 (m, 4H), 7.56−7.52 (m, 2H), 7.50
(d, J = 2.1 Hz, 1H), 7.48−7.43 (m, 1H), 7.39−7.33 (m, 2H), 6.94
(d, J = 2.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ 155.3,
141.9, 141.6, 133.7, 133.2, 132.7, 129.1, 129.0, 128.9, 128.1,
1
2
3
4
5
6
7
8
(36.0 mg, yield 83%); mp = 77−79 oC; Rf = 0.2 (PE/EA = 4:1); 1H
NMR (400 MHz, CDCl3) δ 8.79−8.51 (m, 2H), 7.90 (dt, J = 4.5,
1.3 Hz, 2H), 7.44 (dd, J = 1.8, 1.0 Hz, 1H), 6.83 (dd, J = 1.8, 1.0
Hz, 1H), 4.28 (qd, J = 7.1, 1.0 Hz, 2H), 1.31 (td, J = 7.2, 1.0 Hz,
3H); 13C{1H} NMR (100 MHz, CDCl3) δ 162.9, 153.8, 149.9,
142.5, 136.6, 121.6, 117.0, 113.6, 60.9, 14.2; IR (KBr) ν̃ 2988,
1710, 1488, 1290, 1067, 749 cm−1; HRMS (ESI) calcd. for
C12H12NO3+ [M + H]+: 218.0812, found: 218.0816.
127.7, 127.4, 127.1, 126.7, 125.5, 125.1, 124.2, 113.0; IR (KBr) ν̃
2965, 2917, 2226, 1781, 1479, 1059, 686 cm−1; HRMS (ESI)
calcd. for C20H15O3S+ [M + H]+: 335.0736, found: 335.0735.
2-Methyl-3-(phenylsulfonyl)furan (3x).14b Yellow liquid (31.1
Ethyl [2,2'-bifuran]-3-carboxylate (3p).24 Yellow liquid (24.7
1
mg, yield 60%); Rf = 0.4 (PE/EA = 20:1); H NMR (400 MHz,
9
1
CDCl3) δ 7.67−7.46 (m, 2H), 7.41−7.35 (m, 1H), 6.96−6.70 (m,
1H), 6.53 (dt, J = 3.6, 1.8 Hz, 1H), 4.33 (qd, J = 7.1, 1.7 Hz, 2H),
1.37 (td, J = 7.1, 1.7 Hz, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ
162.8, 148.9, 144.5, 143.4, 141.0, 113.1, 112.8, 112.4, 111.9, 60.5,
14.3.
mg, yield 70%); Rf = 0.3 (PE/EA = 10:1); H NMR (400 MHz,
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
CDCl3) δ 7.92 (d, J = 7.2 Hz, 2H), 7.58 (d, J = 7.2 Hz, 1H), 7.52
(t, J = 7.4 Hz, 2H), 7.25 (d, J = 1.9 Hz, 1H), 6.58 (d, J = 1.8 Hz,
1H), 2.58 (s, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ 156.8,
142.6, 141.2, 133.1, 129.2, 126.9, 122.8, 110.0, 12.9.
Ethyl 2-(thiophen-2-yl)furan-3-carboxylate (3q). Yellow liquid
(33.3 mg, yield 75%); Rf = 0.4 (PE/EA = 20:1); H NMR (400
2-(3-(Phenylsulfonyl)furan-2-yl)benzofuran (3y). Yellow solid
(45.4 mg, yield 70%); mp = 150−151 oC; Rf = 0.3 (PE/EA = 10:1);
1H NMR (400 MHz, CDCl3) δ 8.00 (d, J = 7.8 Hz, 2H), 7.72 (s,
1H), 7.67 (d, J = 7.7 Hz, 1H), 7.55−7.43 (m, 5H), 7.37 (t, J = 7.7
Hz, 1H), 7.28 (t, J = 7.4 Hz, 1H), 6.93 (d, J = 1.9 Hz, 1H);
13C{1H} NMR (100 MHz, CDCl3) δ 155.1, 146.0, 144.0, 142.3,
141.7, 133.6, 129.1, 128.0, 127.1, 126.2, 124.6, 123.7, 122.2,
1
MHz, CDCl3) δ 8.06 (dd, J = 3.8, 1.2 Hz, 1H), 7.42 (dd, J = 5.0,
1.2 Hz, 1H), 7.33 (d, J = 2.0 Hz, 1H), 7.11 (dd, J = 5.1, 3.8 Hz,
1H), 6.80 (d, J = 1.9 Hz, 1H), 4.35 (q, J = 7.1 Hz, 2H), 1.38 (t, J =
7.1 Hz, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ 163.3, 153.0,
140.5, 131.6, 128.8, 127.8, 127.4, 112.7, 112.3, 60.6, 14.4; IR
(KBr) ν
̃
2988, 1726, 1488, 1290, 1074, 741 cm−1; HRMS (ESI)
113.0, 111.5, 109.5; IR (KBr) ν̃ 3132, 2981, 2234, 1781, 1479,
calcd. for C11H11O3S+ [M + H]+: 223.0423, found: 223.0425.
1059, 686 cm−1; HRMS (ESI) calcd. for C18H13O4S+ [M + H]+:
325.0529, found: 325.0529.
Ethyl 2-(tert-butyl)furan-3-carboxylate (3r).25 Yellow liquid
(23.5 mg, yield 60%); Rf = 0.5 (PE/EA = 20:1); H NMR (400
1
2-(Thiophen-2-yl)furan-3-carbonitrile (3z). Brown solid (28.0
o
1
MHz, CDCl3) δ 7.18 (d, J = 1.9 Hz, 1H), 6.68 (d, J = 1.8 Hz, 1H),
4.27 (q, J = 7.1 Hz, 2H), 1.42 (s, 9H), 1.35 (t, J = 7.1 Hz, 3H);
13C{1H} NMR (100 MHz, CDCl3) δ 168.2, 163.8, 138.4, 112.6,
112.2, 60.2, 34.5, 28.2, 14.3.
2-Phenyl-3-(phenylsulfonyl)furan (3s). Yellow liquid (45.4 mg,
yield 80%); Rf = 0.4 (PE/EA = 10:1); 1H NMR (400 MHz, CDCl3)
δ 7.89−7.74 (m, 4H), 7.50 (t, J = 7.5 Hz, 1H), 7.46−7.34 (m, 6H),
6.86 (d, J = 2.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ
155.4, 141.9, 141.5, 133.3, 130.1, 129.0, 128.7, 128.3, 128.2,
mg, yield 80%); mp = 80−82 C; Rf = 0.5 (PE/EA = 10:1); H
NMR (400 MHz, CDCl3) δ 7.74 (dd, J = 3.8, 1.2 Hz, 1H), 7.44
(dd, J = 5.0, 1.2 Hz, 1H), 7.37 (d, J = 2.0 Hz, 1H), 7.13 (dd, J =
5.0, 3.8 Hz, 1H), 6.63 (d, J = 2.0 Hz, 1H); 13C{1H} NMR (100
MHz, CDCl3) δ 156.2, 141.7, 130.0, 128.2, 128.0, 127.0, 114.4,
112.8, 90.5; IR (KBr) ν̃ 3132, 2981, 2234, 1781, 1479, 1059, 686
cm−1; HRMS (ESI) calcd. for C9H6NOS+ [M + H]+: 176.0165,
found: 176.0171.
2-Phenylfuran-3-carbonitrile (3aa).14b Yellow solid (23.7 mg,
yield 70%); Rf = 0.5 (PE/EA = 10:1); 1H NMR (400 MHz, CDCl3)
δ 8.07−7.89 (m, 2H), 7.54−7.37 (m, 4H), 6.67 (d, J = 2.0 Hz, 1H);
13C{1H} NMR (100 MHz, CDCl3) δ 159.9, 142.2, 130.1, 129.1,
128.1, 125.4, 114.9, 113.3, 91.6.
127.0, 123.9, 112.7; IR (KBr) ν̃ 2981, 1710, 1488, 1297, 1067,
749 cm−1; HRMS (ESI) calcd. for C16H13O3S+ [M + H]+:
285.0580, found: 285.0586.
2-(4-Methoxyphenyl)-3-(phenylsulfonyl)furan (3t). Yellow solid
o
(51.5 mg, yield 82%); mp = 78−80 C; Rf = 0.2 (PE/EA = 10:1);
2-(4-Methoxyphenyl)furan-3-carbonitrile (3ab). Brown solid
o
1H NMR (400 MHz, CDCl3) δ 7.80 (t, J = 8.0 Hz, 4H), 7.49 (t, J
= 7.4 Hz, 1H), 7.44−7.33 (m, 3H), 6.93 (d, J = 8.9 Hz, 2H), 6.82
(d, J = 2.0 Hz, 1H), 3.84 (s, 3H); 13C{1H} NMR (100 MHz,
CDCl3) δ 161.1, 155.6, 142.1, 140.9, 133.1, 130.3, 129.0, 126.9,
(33.8 mg, yield 85%); mp = 70−72 C; Rf = 0.4 (PE/EA = 10:1);
1H NMR (400 MHz, CDCl3) δ 7.93 (d, J = 8.9 Hz, 2H), 7.40 (d, J
= 2.1 Hz, 1H), 7.08−6.79 (m, 2H), 6.63 (d, J = 2.1 Hz, 1H), 3.86
(s, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ 161.0, 160.2, 141.4,
122.5, 120.8, 113.8, 112.6, 55.4; IR (KBr) ν
̃
2988, 1710, 1479,
127.1, 121.0, 115.3, 114.5, 113.1, 89.9, 55.4; IR (KBr) ν̃ 3132,
1297, 1074, 749 cm−1; HRMS (ESI) calcd. for C17H15O4S+ [M +
2981, 2226, 1781, 1488, 1059, 686 cm−1; HRMS (ESI) calcd. for
H]+: 315.068, found: 315.0687.
C12H10NO2+ [M + H]+: 200.0706, found: 200.0689.
2-(4-Chlorophenyl)-3-(phenylsulfonyl)furan (3u). Yellow solid
(48.3 mg, yield 76%); mp = 120−121 oC; Rf = 0.3 (PE/EA = 10:1);
1H NMR (400 MHz, CDCl3) δ 7.85−7.77 (m, 4H), 7.53 (t, J = 7.4
Hz, 1H), 7.48−7.36 (m, 5H), 6.84 (d, J = 1.8 Hz, 1H); 13C{1H}
NMR (100 MHz, CDCl3) δ 154.0, 141.8, 141.7, 136.3, 133.4,
2-(p-Tolyl)furan-3-carbonitrile (3ac). Yellow solid (27.8 mg,
o
1
yield 76%); mp = 70−72 C; Rf = 0.5 (PE/EA = 10:1); H NMR
(400 MHz, CDCl3) δ 7.86 (d, J = 8.3 Hz, 2H), 7.42 (d, J = 2.1 Hz,
1H), 7.27 (d, J = 8.1 Hz, 2H), 6.64 (d, J = 2.0 Hz, 1H), 2.39 (s,
3H); 13C{1H} NMR (100 MHz, CDCl3) δ 160.2, 141.8, 140.5,
130.0, 129.1, 128.7, 127.0, 126.7, 124.3, 112.9; IR (KBr) ν
̃
2925,
129.7, 125.4, 125.4, 115.1, 113.2, 90.9, 21.5; IR (KBr) ν̃ 3132,
1591, 1472, 1328, 1154, 726 cm−1; HRMS (ESI) calcd. for
2981, 2226, 1773, 1488, 1059, 686 cm−1; HRMS (ESI) calcd. for
C16H12ClO3S+ [M + H]+: 319.0190, found: 319.0192.
C12H10NO+ [M + H]+: 184.0757, found: 184.0751.
4-(3-(Phenylsulfonyl)furan-2-yl)benzonitrile (3v). Yellow solid
(43.3 mg, yield 70%); mp = 160−161 oC; Rf = 0.2 (PE/EA = 10:1);
1H NMR (400 MHz, CDCl3) δ 8.04 (d, J = 8.4 Hz, 2H), 7.81 (d, J
= 7.7 Hz, 2H), 7.71 (d, J = 8.4 Hz, 2H), 7.56 (t, J = 7.4 Hz, 1H),
7.52 (d, J = 1.7 Hz, 1H), 7.46 (t, J = 7.7 Hz, 2H), 6.86 (d, J = 1.7
Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ 152.4, 142.7, 141.4,
133.7, 132.2, 132.1, 129.2, 129.0, 127.1, 126.2, 118.2, 113.4,
2-(4-Chlorophenyl)furan-3-carbonitrile (3ad). Yellow solid
(24.4 mg, yield 60%); mp = 100−102 oC; Rf = 0.5 (PE/EA = 10:1);
1H NMR (400 MHz, CDCl3) δ 8.12−7.78 (m, 2H), 7.52−7.38 (m,
3H), 6.69 (d, J = 2.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ
158.7, 142.4, 136.2, 129.4, 126.6, 126.5, 114.6, 113.5, 92.1; IR
(KBr) ν
̃
3132, 2973, 2226, 1781, 1479, 1059, 686 cm−1; HRMS
+
(ESI) calcd. for C11H7ClNO3 [M + H]+: 204.0211, found:
113.4; IR (KBr) ν̃
2925, 1591, 1472, 1328, 1139, 717 cm−1;
204.0210.
HRMS (ESI) calcd. for C17H12NO3S+ [M + H]+: 310.0532, found:
310.0533.
Ethyl 2,5-diphenylfuran-3-carboxylate (5a).26 Yellow solid
1
(53.8 mg, yield 83%); Rf = 0.5 (PE/EA = 20:1); H NMR (400
MHz, CDCl3) δ 7.91 (d, J = 7.2 Hz, 2H), 7.78 (t, J = 8.2 Hz, 4H),
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 6 of 9
7.54 (t, J = 7.4 Hz, 1H), 7.48−7.38 (m, 4H), 7.34 (d, J = 7.0 Hz,
149.9, 136.6, 129.2, 128.9, 128.7, 124.3, 121.5, 119.0, 108.5, 61.1,
1
2
3
4
5
6
7
8
4H), 6.95 (s, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ 191.8,
155.0, 152.5, 138.0, 133.0, 129.8, 129.8, 129.1, 128.9, 128.5,
128.4, 128.4, 128.2, 127.5, 124.1, 122.9, 108.7.
14.3; IR (KBr) ν
̃
2988, 1726, 1599, 1479, 1234, 1099, 765 cm−1;
+
HRMS (ESI) calcd. for C18H16NO3 [M + H]+: 294.1125, found:
294.1128.
(2-Methyl-5-phenylfuran-3-yl)(phenyl)methanone
(5b).26
2,5-Diphenyl-3-(phenylsulfonyl)furan (5j). Yellow solid (43.2
1
o
1
Yellow solid (32.5 mg, yield 62%); Rf = 0.5 (PE/EA = 20:1); H
NMR (400 MHz, CDCl3) δ 7.79−7.74 (m, 2H), 7.61−7.55 (m, 2H),
7.54−7.47 (m, 1H), 7.42 (t, J = 7.5 Hz, 2H), 7.31 (t, J = 7.7 Hz,
2H), 7.24 – 7.15 (m, 1H), 6.74 (s, 1H), 2.53 (s, 3H); 13C{1H}
NMR (100 MHz, CDCl3) δ 191.3, 159.0, 151.6, 139.1, 132.2,
130.0, 129.0, 128.8, 128.4, 127.8, 123.7, 122.4, 106.5, 14.4.
2-Phenyl-6,7-dihydrobenzofuran-4(5H)-one (5c).14 white solid
mg, yield 60%); mp = 144−146 C; Rf = 0.2 (PE/EA = 10:1); H
NMR (400 MHz, CDCl3) δ 7.99−7.91 (m, 2H), 7.88−7.82 (m, 2H),
7.73−7.66 (m, 2H), 7.55−7.48 (m, 1H), 7.48−7.39 (m, 7H),
7.37−7.31 (m, 1H), 7.11 (s, 1H); 13C{1H} NMR (100 MHz,
CDCl3) δ 154.1, 152.8, 141.8, 133.3, 130.1, 129.0, 129.0, 128.9,
128.7, 128.7, 128.4, 128.3, 127.1, 125.7, 124.2, 107.3; IR (KBr) ν
̃
9
3068, 2933, 1599, 1297, 1146, 734 cm−1; HRMS (ESI) calcd. for
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(29.7 mg, yield 70%); Rf = 0.4 (PE/EA = 10:1); H NMR (400
C22H17O3S+ [M + H]+: 361.0893, found: 361.0887.
1
MHz, CDCl3) δ 7.69−7.61 (m, 2H), 7.40 (t, J = 7.6 Hz, 2H), 7.30
(t, J = 7.5 Hz, 1H), 6.89 (s, 1H), 2.96 (t, J = 6.2 Hz, 2H), 2.54 (t, J
= 6.4 Hz, 2H), 2.22 (p, J = 6.3 Hz, 2H); 13C{1H} NMR (100 MHz,
CDCl3) δ 194.6, 166.7, 154.2, 129.8, 128.8, 128.1, 124.0, 122.9,
100.9, 37.7, 23.5, 22.6.
5-Phenyl-2-(thiophen-2-yl)furan-3-carbonitrile (5k). Brown
solid (30.6 mg, yield 61%); mp = 104−106 oC; Rf = 0.5 (PE/EA =
10:1); H NMR (400 MHz, CDCl3) δ 7.81 (dd, J = 3.8, 1.1 Hz,
1H), 7.69 (d, 2H), 7.50−7.41 (m, 3H), 7.37 (t, 1H), 7.17 (t, J = 5.0,
3.8 Hz, 1H), 6.82 (s, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ
155.1, 153.2, 130.1, 129.0, 128.9, 128.5, 128.3, 127.9, 126.9,
1
Ethyl 2,5-diphenylfuran-3-carboxylate (5d).25 Yellow solid
1
(43.2 mg, yield 74%); Rf = 0.5 (PE/EA = 20:1); H NMR (400
124.2, 114.4, 107.1, 92.3; IR (KBr) ν̃ 3125, 2226, 1583, 1479, 749,
MHz, CDCl3) δ 8.09 (d, J = 7.1 Hz, 2H), 7.75 (d, J = 7.4 Hz, 2H),
7.50−7.40 (m, 5H), 7.32 (t, J = 7.4 Hz, 1H), 7.11 (s, 1H), 4.35 (q,
J = 7.1 Hz, 2H), 1.38 (t, J = 7.1 Hz, 3H); 13C{1H} NMR (100
MHz, CDCl3) δ 163.6, 156.5, 152.4, 129.8, 129.4, 128.8, 128.4,
128.2, 128.1, 124.0, 115.8, 107.9, 60.7, 14.3.
686 cm−1; HRMS (ESI) calcd. for C15H10NOS+ [M + H]+:
252.0478, found: 252.0508.
2,5-Diphenylfuran-3-carbonitrile (5l).10 Yellow solid (38.2 mg,
yield 78%); Rf = 0.5 (PE/EA = 10:1); 1H NMR (400 MHz, CDCl3)
δ 8.06 (d, J = 7.5 Hz, 2H), 7.72 (d, J = 7.3 Hz, 2H), 7.55−7.33 (m,
6H), 6.86 (s, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ 158.7,
153.7, 130.1, 129.1, 129.0, 128.9, 128.7, 128.1, 125.4, 124.2,
114.9, 107.7, 93.4.
Ethyl 5-phenyl-2-(p-tolyl)furan-3-carboxylate (5e).28 Yellow
1
solid (37.9 mg, yield 62%); Rf = 0.5 (PE/EA = 20:1); H NMR
(400 MHz, CDCl3) δ 7.97 (d, J = 8.2 Hz, 2H), 7.72 (d, J = 7.4 Hz,
2H), 7.40 (t, J = 7.6 Hz, 2H), 7.32−7.22 (m, 3H), 7.07 (s, 1H),
4.32 (q, J = 7.1 Hz, 2H), 2.40 (s, 3H), 1.36 (t, J = 7.1 Hz, 3H);
13C{1H} NMR (100 MHz, CDCl3) δ 163.6, 156.9, 152.0, 139.5,
129.9, 128.9, 128.8, 128.3, 128.0, 127.1, 124.0, 115.3, 107.9, 60.6,
21.5, 14.3.
2-(4-Methoxyphenyl)-5-phenylfuran-3-carbonitrile
(5m).10
1
Yellow solid (40.2 mg, yield 73%); Rf = 0.4 (PE/EA = 10:1); H
NMR (400 MHz, CDCl3) δ 7.99 (d, J = 8.9 Hz, 2H), 7.68 (d, J =
7.4 Hz, 2H), 7.43 (t, J = 7.6 Hz, 2H), 7.35 (t, J = 7.4 Hz, 1H),
7.01 (d, J = 8.9 Hz, 2H), 6.80 (s, 1H), 3.87 (s, 3H); 13C{1H} NMR
(100 MHz, CDCl3) δ 161.0, 159.1, 152.9, 128.9 (2C), 128.7,
128.5, 127.1, 124.1, 121.0, 115.3, 114.5 (2C), 107.5, 91.6, 55.4.
2-(4-Chlorophenyl)-5-phenylfuran-3-carbonitrile (5n). Yellow
solid (35.1 mg, yield 63%); mp = 127−129 oC; Rf = 0.5 (PE/EA =
Ethyl 2-(4-fluorophenyl)-5-phenylfuran-3-carboxylate (5f).
o
Yellow solid (36.0 mg, yield 58%); mp = 60−62 C; Rf = 0.5
1
(PE/EA = 20:1); H NMR (400 MHz, CDCl3) δ 8.14 – 8.02 (m,
2H), 7.71 (d, J = 7.4 Hz, 2H), 7.41 (t, J = 7.7 Hz, 2H), 7.30 (t, J =
7.4 Hz, 1H), 7.14 (t, J = 8.7 Hz, 2H), 7.06 (s, 1H), 4.32 (q, J = 7.1
Hz, 2H), 1.36 (t, J = 7.1 Hz, 3H); 13C{1H} NMR (100 MHz,
CDCl3) δ 163.5, 163.3 (JC-F = 250.4 Hz), 155.6, 152.3, 130.5 (JC-F
= 8.6 Hz), 129.7, 128.8, 128.2, 126.1 (JC-F = 3.3 Hz), 124.0, 115.6,
1
10:1); H NMR (400 MHz, CDCl3) δ 7.98 (d, J = 8.6 Hz, 2H),
7.70 (d, J = 7.3 Hz, 2H), 7.49−7.42 (m, 4H), 7.38 (t, J = 7.3 Hz,
1H), 6.86 (s, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ 157.5,
154.0, 136.1, 129.4, 129.2, 129.1, 129.0, 128.5, 126.5, 124.3,
115.2 (JC-F = 21.8 Hz), 107.9, 60.7, 14.3; IR (KBr) ν
̃
2928, 1607,
114.7, 107.8, 93.8; IR (KBr) ν̃ 3116, 2917, 2226, 1479, 1091, 829,
1490, 1210, 1049, 829 cm−1; HRMS (ESI) calcd. for C19H16FO3
[M + H]+: 311.1078, found: 311.1073.
686 cm−1; HRMS (ESI) calcd. for C17H11ClNO+ [M + H]+:
280.0524, found: 280.0528.
+
Ethyl 2-(4-chlorophenyl)-5-phenylfuran-3-carboxylate (5g).29
Yellow solid (35.2 mg, yield 54%) Rf = 0.5 (PE/EA = 20:1); H
2-(tert-Butyl)-5-phenylfuran-3-carbonitrile (5o). Yellow liquid
1
1
(31.5 mg, yield 70%); Rf = 0.5 (PE/EA = 10:1); H NMR (400
NMR (400 MHz, CDCl3) δ 8.06 (d, J = 8.7 Hz, 2H), 7.73 (d, J =
7.5 Hz, 2H), 7.46−7.40 (m, 4H), 7.33 (t, J = 7.4 Hz, 1H), 7.09 (s,
1H), 4.34 (q, J = 7.1 Hz, 2H), 1.38 (s, 3H); 13C{1H} NMR (100
MHz, CDCl3) δ 163.4, 155.2, 152.6, 135.3, 129.6, 129.6, 128.8,
128.4, 128.2, 124.1, 116.2, 108.0, 60.8, 24.3, 14.3.
MHz, CDCl3) δ 7.61 (d, J = 7.3 Hz, 2H), 7.41 (t, J = 7.5 Hz, 2H),
7.32 (t, J = 7.4 Hz, 1H), 6.68 (s, 1H), 1.50 (s, 9H); 13C{1H} NMR
(100 MHz, CDCl3) δ 170.4, 152.2, 129.1, 128.9, 128.5, 123.9,
114.9, 106.6, 92.4, 34.9, 28.9; IR (KBr) ν̃ 2973, 2218, 1790, 1488,
1178, 1074, 757 cm−1; HRMS (ESI) calcd. for C15H16NO+ [M +
Ethyl 2-(4-bromophenyl)-5-phenylfuran-3-carboxylate (5h).
H]+: 226.1226, found: 226.1230.
o
Yellow solid (39.2 mg, yield 53%); mp = 64−66 C; Rf = 0.5
Phenyl(2-phenyl-5-(p-tolyl)furan-3-yl)methanone (6a). Yellow
1
1
(PE/EA = 20:1); H NMR (400 MHz, CDCl3) δ 8.00 (d, J = 8.6
liquid (40.6 mg, yield 60%); Rf = 0.5 (PE/EA = 10:1); H NMR
Hz, 2H), 7.73 (d, J = 7.4 Hz, 2H), 7.59 (d, J = 8.6 Hz, 2H), 7.43 (t,
J = 7.6 Hz, 2H), 7.33 (t, J = 7.4 Hz, 1H), 7.08 (s, 1H), 4.34 (q, J =
7.1 Hz, 2H), 1.38 (t, J = 7.1 Hz, 3H); 13C{1H} NMR (100 MHz,
CDCl3) δ 163.4, 155.2, 152.6, 131.4, 129.8, 129.6, 128.9, 128.7,
(400 MHz, CDCl3) δ 7.88 (d, J = 7.3 Hz, 2H), 7.79−7.73 (m, 2H),
7.63 (d, J = 8.1 Hz, 2H), 7.50 (t, J = 7.4 Hz, 1H), 7.38 (t, J = 7.7
Hz, 2H), 7.34−7.25 (m, 3H), 7.21 (d, J = 8.0 Hz, 2H), 6.85 (s, 1H),
2.36 (s, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ 191.8, 154.7,
152.8, 138.2, 138.1, 132.9, 129.8, 129.8, 129.6, 128.9, 128.4,
128.3, 124.1, 123.6, 116.3, 108.1, 60.8, 14.3; IR (KBr) ν̃ 2933,
1710, 1225, 1099, 837, 694 cm−1; HRMS (ESI) calcd. for
128.4, 127.4, 127.1, 124.1, 122.8, 108.0, 21.4; IR (KBr) ν̃ 3061,
C19H16BrO3+ [M + H]+: 371.0277, found: 371.0281.
2925, 1662, 1488, 1242, 885, 694 cm−1; HRMS (ESI) calcd. for
Phenyl(5-phenyl-2-(pyridin-4-yl)furan-3-yl)methanone
(5i).
C24H19O2+ [M + H]+: 339.1380, found: 339.1376.
o
Yellow solid (35.7 mg, yield 61%); mp = 70−72 C; Rf = 0.4
(PE/EA = 4:1); 1H NMR (400 MHz, CDCl3) δ 8.70 (d, J = 5.3 Hz,
2H), 8.11−7.98 (m, 2H), 7.81−7.69 (m, 2H), 7.44 (t, 2H), 7.35 (t,
1H), 7.11 (s, 1H), 4.36 (q, J = 7.1 Hz, 2H), 1.39 (t, J = 7.1 Hz,
3H); 13C{1H} NMR (100 MHz, CDCl3) δ 163.0, 153.8, 152.7,
Phenyl(2-phenyl-5-(m-tolyl)furan-3-yl)methanone (6b). Yellow
1
liquid (43.9 mg, yield 65%); Rf = 0.5 (PE/EA = 10:1); H NMR
(400 MHz, CDCl3) δ 7.88 (d, J = 7.2 Hz, 2H), 7.78 (d, J = 6.8 Hz,
2H), 7.52 (m, 3H), 7.38 (t, J = 7.1 Hz, 2H), 7.29 (t, J = 7.2 Hz,
4H), 7.11 (d, J = 7.2 Hz, 1H), 6.89 (s, 1H), 2.39 (s, 3H); 13C{1H}
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The Journal of Organic Chemistry
1
NMR (100 MHz, CDCl3) δ 191.8, 154.9, 152.7, 138.6, 138.1,
132.9, 129.8, 129.7, 129.1, 129.0, 128.8, 128.4, 128.4, 127.5,
0.4 (PE/EA = 10:1); H NMR (400 MHz, CDCl3) δ 8.21 (d, J =
1.7 Hz, 1H), 7.98−7.71 (m, 8H), 7.57−7.26 (m, 8H), 7.01 (s, 1H);
13C{1H} NMR (100 MHz, CDCl3) δ 191.7, 155.2, 152.6, 138.1,
133.5, 133.1, 133.0, 129.8, 129.8, 129.1, 128.7, 128.4, 128.4,
128.3, 127.9, 127.5, 127.1, 126.7, 126.4, 123.0, 122.8, 122.2,
1
2
3
4
5
6
7
8
124.7, 122.9, 121.3, 108.6, 21.5; IR (KBr) ν̃ 3052, 2925, 1655,
+
1479 1234, 885, 694 cm−1; HRMS (ESI) calcd. for C24H19O2 [M
+ H]+: 339.1380, found: 339.1376.
Phenyl(2-phenyl-5-(o-tolyl)furan-3-yl)methanone (6c). Yellow
109.3; IR (KBr) ν
̃
3068, 2925, 1662, 1488 1242, 734, 472 cm−1;
1
+
liquid (40.6 mg, yield 60%); Rf = 0.5 (PE/EA = 10:1); H NMR
HRMS (ESI) calcd. for C27H19O2 [M + H]+: 375.1380, found:
375.1382.
(400 MHz, CDCl3) δ 7.92 (d, J = 7.2 Hz, 2H), 7.85−7.75 (m, 3H),
7.54 (t, J = 7.4 Hz, 1H), 7.42 (t, J = 7.7 Hz, 2H), 7.36−7.27 (m,
6H), 6.85 (s, 1H), 2.58 (s, 3H); 13C{1H} NMR (100 MHz, CDCl3)
δ 191.9, 154.7, 152.3, 138.1, 135.0, 133.0, 131.4, 129.8, 129.8,
129.1, 129.0, 128.4, 128.3, 127.5, 127.2, 126.2, 122.6, 112.1, 22.0;
(E)-phenyl(2-phenyl-5-styrylfuran-3-yl)methanone (6j). Yellow
liquid (50.4 mg, yield 72%); Rf = 0.5 (PE/EA = 10:1); H NMR
1
(400 MHz, CDCl3) δ 7.86 (dd, J = 8.3, 1.4 Hz, 2H), 7.77 (dd, J =
7.9, 1.9 Hz, 2H), 7.50 (dd, J = 7.7, 2.1 Hz, 3H), 7.43–7.25 (m,
8H), 7.19 (d, J = 16.3 Hz, 1H), 6.90 (d, J = 16.3 Hz, 1H), 6.61 (s,
1H); 13C{1H} NMR (100 MHz, CDCl3) δ 191.6, 155.1, 151.8,
138.0, 136.6, 133.0, 129.8, 129.7, 129.1, 129.0, 128.8, 128.5,
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
IR (KBr) ν̃
3068, 2925, 1733, 1448 1224, 1043, 717 cm−1; HRMS
(ESI) calcd. for C24H19O2+ [M + H]+: 339.1380, found: 339.1376.
(5-(4-(tert-Butyl)phenyl)-2-phenylfuran-3-
yl)(phenyl)methanone (6d). Yellow solid (53.2 mg, yield 70%);
128.4, 128.1, 127.5, 126.6, 122.8, 115.5, 112.1; IR (KBr) ν̃ 3068,
2925, 1662, 1488 1225, 892, 694 cm−1; HRMS (ESI) calcd. for
o
1
mp = 64−67 C; Rf = 0.5 (PE/EA = 10:1); H NMR (400 MHz,
CDCl3) δ 7.91 (d, J = 7.5 Hz, 2H), 7.80 (dd, J = 8.0, 1.7 Hz, 2H),
7.71 (d, J = 8.4 Hz, 2H), 7.54 (t, J = 7.4 Hz, 1H), 7.47 (d, J = 8.5
Hz, 2H), 7.41 (t, J = 7.7 Hz, 2H), 7.37−7.30 (m, 3H), 6.90 (s, 1H),
1.37 (s, 9H); 13C{1H} NMR (100 MHz, CDCl3) δ 191.9, 154.7,
152.7, 151.4, 138.1, 132.9, 129.8, 129.8, 128.9, 128.4, 128.4,
127.4, 127.1, 125.8, 124.0, 122.8, 108.2, 34.8, 31.3; IR (KBr) ν
3068, 2917, 1662, 1496 1232, 885, 686 cm−1; HRMS (ESI) calcd.
for C27H25O2+ [M + H]+: 381.1849, found: 381.1854.
C25H19O2+ [M + H]+: 351.1380, found: 351.1382.
Phenyl(2-phenyl-5-(phenylethynyl)furan-3-yl)methanone (6k).
Yellow liquid (48.7 mg, yield 70%); Rf = 0.5 (PE/EA = 10:1); 1H
NMR (400 MHz, CDCl3) δ 7.88 (d, J = 8.5 Hz, 2H), 7.78 (dd, J =
6.8, 3.0 Hz, 2H), 7.62−7.51 (m, 3H), 7.44−7.37 (m, 5H), 7.33 (dd,
J = 4.9, 1.9 Hz, 3H), 6.92 (s, 1H); 13C{1H} NMR (100 MHz,
CDCl3) δ 191.0, 156.2, 137.8, 135.8, 133.1, 131.6, 129.8, 129.5,
129.2, 129.1, 128.5, 128.5, 128.4, 127.7, 121.9, 121.9, 118.7, 94.8,
̃
(5-(4-Methoxyphenyl)-2-phenylfuran-3-yl)(phenyl)methanone
78.7; IR (KBr) ν
̃
3068, 2933, 1662, 1479 1273, 892, 686 cm−1;
+
(6e).17d Yellow solid (45.3 mg, yield 64%); Rf = 0.4 (PE/EA =
HRMS (ESI) calcd. for C25H17O2 [M + H]+: 349.1223, found:
1
10:1); H NMR (400 MHz, CDCl3) δ 7.90 (d, J = 7.3 Hz, 2H),
349.1230.
7.77 (d, J = 6.5 Hz, 2H), 7.69 (d, J = 8.9 Hz, 2H), 7.53 (t, J = 7.4
Hz, 1H), 7.40 (t, J = 7.6 Hz, 2H), 7.32 (d, J = 7.8 Hz, 3H), 6.97 (d,
J = 8.9 Hz, 2H), 6.80 (s, 1H), 3.85 (s, 3H); 13C{1H} NMR (100
MHz, CDCl3) δ 191.9, 159.7, 154.4, 152.6, 138.1, 132.9, 129.9,
129.8, 128.8, 128.4, 128.3, 127.4, 125.6, 122.9, 122.8, 114.4,
107.2, 55.4.
(5-Phenethyl-2-phenylfuran-3-yl)(phenyl)methanone
(6l).
Yellow liquid (43.6 mg, yield 62%); Rf = 0.5 (PE/EA = 10:1); 1H
NMR (400 MHz, CDCl3) δ 7.82 (d, J = 7.2 Hz, 2H), 7.46 (t, J =
7.4 Hz, 1H), 7.43−7.39 (m, 2H), 7.31 (t, J = 7.7 Hz, 2H),
7.25−7.05 (m, 9H), 2.87−2.67 (m, 4H); 13C{1H} NMR (100 MHz,
CDCl3) δ 193.7, 154.2, 141.3, 139.1, 137.7, 133.3, 129.9, 129.8,
128.5, 128.4, 128.4, 128.3, 128.3, 126.9, 126.8, 126.0, 121.0, 36.0,
(5-(4-fluorophenyl)-2-phenylfuran-3-yl)(phenyl)methanone (6f).
Yellow solid (53.4 mg, yield 78%); mp = 90−92 C; Rf = 0.4
25.9; IR (KBr) ν
̃
3061, 2925, 2250, 2123 1662, 1072, 749 cm−1;
o
(PE/EA = 10:1); H NMR (400 MHz, CDCl3) δ 7.87 (d, J = 7.7
HRMS (ESI) calcd. for C25H21O2 [M + H]+: 353.1536, found:
353.1542.
1
+
Hz, 2H), 7.83−7.63 (m, 4H), 7.51 (t, J = 7.3 Hz, 1H), 7.38 (t, J =
7.7 Hz, 2H), 7.33–7.26 (m, 3H), 7.11 (t, J = 8.7 Hz, 2H), 6.85 (s,
1H); 13C{1H} NMR (100 MHz, CDCl3) δ 191.7, 162.6 (JC-F
=
■ ASSOCIATED CONTENT
247.0 Hz), 155.0, 151.7, 138.0, 133.0, 129.8, 129.6, 129.1,
128.4(JC-F = 3.0 Hz), 127.5, 126.2(JC-F = 3.0 Hz), 125.9 (JC-F
Supporting Information
=
9.0 Hz), 122.9, 116.0 (JC-F = 22.0 Hz), 108.4, 108.4; IR (KBr) ν
3068, 2925, 1662, 1496 1234, 900, 694 cm−1; HRMS (ESI) calcd.
for C23H16FO2+ [M + H]+: 343.1129, found: 343.1124.
̃
The Supporting Information is available free of charge on the
ACS Publications website at http://pubs.acs.org.
Copies of 1H and 13C NMR spectra for all compounds
X-ray crystallography of compound 3n (CIF)
(5-(4-Chlorophenyl)-2-phenylfuran-3-yl)(phenyl)methanone
(6g). Yellow solid (50.8 mg, yield 71%); mp = 94−96 oC; Rf = 0.4
1
(PE/EA = 10:1); H NMR (400 MHz, CDCl3) δ 7.89 (d, J = 7.3
■ AUTHOR INFORMATION
Hz, 2H), 7.83−7.73 (m, 2H), 7.68 (d, J = 8.5 Hz, 2H), 7.53 (t, J =
7.4 Hz, 1H), 7.46−7.29 (m, 7H), 6.92 (s, 1H); 13C{1H} NMR (100
MHz, CDCl3) δ 191.5, 155.2, 151.4, 137.9, 133.9, 133.0, 129.7,
129.6, 129.2, 129.1, 128.4, 128.4, 128.3, 127.5, 125.3, 122.9,
Corresponding Author
*E-mail: zhaojf@jxnu.edu.cn
109.1; IR (KBr) ν
̃
3068, 2925, 1678, 1496 1234, 694, 495 cm−1;
ORCID
+
HRMS (ESI) calcd. for C23H16ClO2 [M + H]+: 359.0833, found:
Zhenming Zhang: 0000-0001-8550-5398
Junfeng Zhao: 0000-0003-4843-4871
359.0839.
(5-(4-Bromophenyl)-2-phenylfuran-3-yl)(phenyl)methanone
(6h). Yellow solid (56.3 mg, yield 70%); mp = 90−92 oC; Rf = 0.4
1
Notes
(PE/EA = 10:1); H NMR (400 MHz, CDCl3) δ 7.88 (d, J = 7.2
The authors declare no competing financial interests.
Hz, 2H), 7.79−7.71 (m, 2H), 7.62 (d, J = 8.6 Hz, 2H), 7.58−7.50
(m, 3H), 7.40 (t, J = 7.7 Hz, 2H), 7.33 (dd, J = 5.2, 1.8 Hz, 3H),
6.94 (s, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ 155.3, 151.5,
■ ACKNOWLEDGMENT
137.9, 133.0, 132.1, 129.8, 129.7, 129.5, 129.2, 128.7, 128.4,
This work was supported by the National Natural Science
Foundation of China (21762021), and the Science and
Technology Project of Jiangxi Provincial Education Department
(GJJ150297, GJJ150324).
128.4, 127.5, 125.5, 122.9, 122.1, 109.2; IR (KBr) ν̃ 3068, 2933,
1662, 1472 1242, 892, 495 cm−1; HRMS (ESI) calcd. for
C23H16BrO2+ [M + H]+: 403.0328, found: 403.0332.
(5-(Naphthalen-2-yl)-2-phenylfuran-3-yl)(phenyl)methanone
o
(6i). Yellow solid (44.8 mg, yield 60%); mp = 100−102 C; Rf =
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derivatives. Org. Biomol. Chem. 2017, 15, 7824−7829.
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