Synthesis of heterocycle-tethered acylbenzofurans and benzodifurans from odorless and recyclable organoseleno polystyrene resin

Article abstract of DOI:10.1039/c4ra08441a

Organoseleno polystyrene resin-supported synthesis provided quick access to a series of acylbenzofuran derivatives tethered to isoxazoles, triazoles and isoxazolines as well as benzodifurans. Although this methodology proceeded through multiple steps such

Full text of DOI:10.1039/c4ra08441a

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Synthesis of heterocycle-tethered acylbenzofurans
and benzodifurans from odorless and recyclable
organoseleno polystyrene resin†
Cite this: RSC Adv., 2014, 4, 49170
c
a
c
Yuguang Wang,a Bingchun Zhu,ab Qing Xu, Qing Zhu and Lei Yu
*
*
Organoseleno polystyrene resin-supported synthesis provided quick access to a series of acylbenzofuran
derivatives tethered to isoxazoles, triazoles and isoxazolines as well as benzodifurans. Although this
methodology proceeded through multiple steps such as the seleno-induced attachment, nucleophilic
substitutions, 1,3-dipolar cycloadditions, and syn-selenoxide eliminations from organoseleno resin, the
overall product yields were generally good. The concise and safe procedures, wide application scope,
lack of odor, stability and recyclability of the organoseleno resin, and the good yields and high purity of
products are the advantages of this work over the more traditional solution-based chemistry.
Received 10th August 2014
Accepted 26th September 2014
DOI: 10.1039/c4ra08441a
www.rsc.org/advances
their high photoelectric activity.8 Thus, building these organic
skeletons rapidly affords powerful tools for both drug discovery
Introduction
and new material development. Our group aimed to develop
concise and green methodologies with high efficiency that
might be applicable in organic synthesis, pharmaceutical
chemistry, agriculture chemistry and chemical industry.9
Recently, we developed a quick access to heterocycle-tethered
acylbenzofurans and benzodifurans through organoseleno
resin-supported solid-phase synthesis. Herein, we wish to
report our ndings.
Solid-phase synthesis (SPS) is a powerful tool for the rapid
generation of small, drug-like organic molecular libraries for
the purpose of medicinal chemistry programs in the pharma-
ceutical industry.1 Due to the high reactivity of selenium
moieties and the removable properties through clean syn-
selenoxide elimination2 aer preparations, the safe, odorless,
stable, and recyclable organoseleno polystyrene resin is a good
carrier for solid-phase synthesis.3,4 Among reported works, a
series of useful bioactive heterocycles have been synthesized
from organoseleno resins, such as isoxazoles, oxadiazoles, tri-
azoles, uracils, pyrrolines, indulines and others.3 Besides,
organoseleno resin-supported solid-phase synthesis is also a
reliable and practical methodology that has already been widely
applied in natural product synthesis.4
On the other hand, benzofuran skeletons are oen found in
natural products with antimicrobial, antioxidant, anticancer
and anti-inammatory activities.5 They are also important
intermediates in organic synthesis.6 Among these analogues,
acylbenzofurans and heterocycle-tethered benzofurans are very
common moieties in many drug molecules such as Vilazodone,
Dronedarone, Amiodarone, Benzbromarone and others.7 In addi-
tion, they are also widely employed in material science due to
Results and discussion
Based on our previous cooperation research project with certain
companies,10 we chose compound 1 as the starting material.
Aer attachment with organoseleno resin 2 (Br 1.25 mmol gꢀ1),
the mother heterocycle 5,7-dibenzoyl-2,3-dihydrobenzofuran-
4-ol was constructed and uploaded to generate the functional-
ized resin 3 (eqn (1)). This procedure was monitored by Fourier
transform infrared (FT-IR) spectroscopy, which showed a strong
peak of the carbonyl absorptions at 1654–1658 cmꢀ1 on the
resin. The reaction was terminated in 5 h, aer which the
carbonyl absorption did not increase any further.
aCollege of Biological and Environmental Engineering, Zhejiang University of
Technology, Hangzhou, Zhejiang, 310014, P. R. China. E-mail: zhuq@zjut.edu.cn;
Fax: +86-0571-88320781; Tel: +86-18329193166
(1)
bZhejiang Research Institute of Chemical Industry, Hangzhou, Zhejiang, 310023, P. R.
China
cSchool of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou,
Jiangsu 225002, China. E-mail: yulei@yzu.edu.cn; Web: http://blog.sciencenet.cn/u/
YuLei82; Fax: +86-514-87975244; Tel: +86-136-65295901
With the uploaded mother heterocycle resin 3 in hand, we
then tried to modify its hydroxyl group on aromatic ring with
propargyl bromide according to known methodologies.11
† Electronic supplementary information (ESI) available: Detailed table for Fig. 1
and NMR spectra copies of the products. See DOI: 10.1039/c4ra08441a
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However, aer heating 3 with propargyl bromide and K2CO3 in alkyne group. Isoxazole-tethered benzofurans 9 were rst
acetone at 60 ꢁC for 5 h (Table 1, run 1), the IR spectra of resin synthesized through the cycloaddition of aldoximes with resin 4
showed a weak peak of C^C absorption at 2130 cmꢀ1 but a very and the following syn-selenoxide elimination.13 Results
broad and strong absorption peak of O–H, revealing that only a summarized in Table 2 showed that this methodology could
few of resin 3 was modied. The modied product 5 and produce isoxazole-tethered benzofurans 9 comprehensively and
unmodied product 6 were then cut down from resin by syn- the overall product yields and purities were satisfactory.
selenoxide elimination.12,13 and the modication efficiencies Generally, there is no appreciable difference between electron-
were quantitatively evaluated according to the yield and purity with drawing group (EWG) and electron-donation group (EDG)
of 5. It was shown that the reported methodologies afforded in product yields (Table 2, runs 1–3 vs. 4–9). Bulky aldoximes
crude 5 at a very low yield and purity (Table 1, run 1). Obviously, afforded worse results than normal ones (Table 2, runs 8–9 vs.
10 h was the best reaction time (run 2), aer which the reaction 4–5; runs 12 vs. 10–11). The crude product purities for most
could not be improved any more (Table 1, run 3). Replacing examples (Table 2, runs 1–11) were high, providing a concise
K2CO3 with the organic base Et3N slightly improved the yield synthetic methodology especially in product separation.
and purity of 5 (Table 1, run 4) and further solvent screening
Similarly, 1,3-dipolar cycloadditions of resin 4 with azides
demonstrated that DMF–CHCl3 (1 : 1) was a better solvent, and the following syn-selenoxide elimination led to a series of
affording 5 in the highest yield and purity in Table 1 (Table 1, triazole-tethered benzofurans 12 (Table 3). The results were
run 8 vs. 4–7).
even better than preparations of isoxazole-tethered 9 (Table 3
Obtaining optimized conditions for the modication of resin vs. Table 2). This methodology had a broad application scope;
3 with propargyl bromide, it was then convenient to synthesize both electron-rich and -decient aryl azides afforded the
heterocycle-tethered benzofurans via the cyclizations of its corresponding triazole-tethered benzofurans in good yields
with high purity (Table 3, runs 1–8). The steric hindrances of
substrates did not affect the reactions much, since the bulky
azides led to similar product yields and purities with normal
Table 1 Reaction condition evaluation for the modification of polymer
ones (Table 3, runs 1–3 vs. 4–8). Alkyl azide also gave satis-
resin 3 to 4a
factory results in both product yield and purity
(Table 3, run 9).
Table 2 Preparation of isoxazole-tethered benzofuransa
Run
R (7)
9: Yieldb/%
Purityc/%
1
2
3
4
5
6
7
8
C6H5 (7a)
9a: 73
9b: 72
9c: 71
9d: 68
9e: 69
9f: 66
9g: 62
9h: 65
9i: 63
9j: 69
9k: 70
9l: 56
92
91
91
90
90
89
86
88
86
90
90
76
4-MeC6H4 (7b)
4-MeOC6H4 (7c)
4-BrC6H4 (7d)
4-ClC6H4 (7e)
4-FC6H4 (7f)
4-NO2C6H4 (7g)
3-BrC6H4 (7h)
2-ClC6H4 (7i)
c-C6H11 (7j)
Run
Solvent
Base
t/h
yieldb/%
purityc/%
1
2
3
4
5
6
7
8
Acetone
Acetone
Acetone
Acetone
THF
DMF
CHCl3
DMF–CHCl3 (1 : 1)
K2CO3
K2CO3
K2CO3
Et3N
Et3N
Et3N
5
10
15
10
10
10
10
10
59
70
70
72
76
85
86
88
64
72
71
74
80
90
91
94
9
10
11
12
n-C4H9 (7k)
t-C4H9 (7l)
Et3N
Et3N
a
Resin 4 (prepared from 0.8 g resin 2), aldoxime 7 (5 mmol), N-
a
Resin 3 (prepared from 0.8 g resin 2), base (5 mmol) and propargyl
chlorosuccinimide (NCS, 5 mmol) and Et3N (6 mmol) were heated in
bromide (5 mmol) were heated in 15 mL of solvent at 60 ꢁC under N2.
b
35 mL of CH2Cl2 at 35 ꢁC under N2. Isolated yields of crude product
b
Isolated yields of crude product 5 based on Br loading of resin 2.
Purities of product 5 were determined by HPLC analysis.
c
9 based on Br loading of resin 2. Purities of product 9 were
c
determined by HPLC analysis.
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Table 3 Preparation of triazole-tethered benzofuransa
afforded allylic-modied organoseleno polystyrene resin 13
(eqn (2)), which could be employed to synthesize isoxazoline-
tethered benzofurans through further cycloadditions with
aldoximes and the following syn-selenoxide eliminations (Table
4). The methodology had a wide application scope and electron-
rich (Table 4, runs 1–2) and -decient (Table 4, runs 3–7) aryl
aldoximes and alkyl aldoxime (Table 4, run 8) were all appli-
cable substrates. The product yields and purities were satis-
factory in spite of multiple steps of reactions (Table 4, runs 1–8).
Run
R (10)
12: Yieldb/%
Purityc/%
1
2
3
4
5
6
7
8
9
C6H5 (10a)
4-BrC6H4 (10b)
4-Py (10c)
2-MeC6H4 (10d)
2,5-Cl2C6H3 (10e)
2-Cl-4-NO2C6H3 (10f)
2-NO2-4-ClC6H3 (10g)
2,4,5-Cl3C6H2 (10h)
i-C3H7 (10i)
12a: 77
12b: 75
12c: 73
12d: 72
12e: 72
12f: 70
12g: 69
12h: 70
12i: 62
93
92
91
91
91
90
90
90
82
(2)
In addition, nucleophilic substitutions of resin 3 with EWG
and bromo bis-substituted hydrocarbons 16 led to modied
resin 17 as expected (eqn (3)). However, it was very interesting
that cyclizations occurred in the syn-seleno elimination step of
17. The intramolecular nucleophilic substitutions generated a
new fused furan ring. Instead of the originally desired product
20, these unexpected cyclizations led to benzodifuran
a
Resin 4 (prepared from 0.8 g resin 2), RN3 10 (5 mmol), CuSO4$5H2O
(4 mmol) and ascorbic acid (4.5 mmol) were heated in 30 mL of DMSO at
b
60 ꢁC under N2. Isolated yields of crude product 12 based on Br
c
loading of resin 2. Purities of product 12 were determined by HPLC
analysis.
As an activated nucleophilic group, the hydroxyl on resin 3
could react with many types of electrophiles. Reactions with
allylic bromide under similar conditions (Table 1, run 8),
Table 5 Preparation of benzodifuransa
Table 4 Preparation of isoxazoline-tethered benzofuransa
Run
R (7)
15: Yieldb/%
Purityc/%
Run
EWG, R (16)
18 or 19: Yieldb/%
Purityc/%
1
2
3
4
5
6
7
8
4-MeC6H4 (7b)
4-MeOC6H4 (7c)
4-ClC6H4 (7e)
4-FC6H4 (7f)
4-NO2C6H4 (7g)
3-BrC6H4 (7h)
2-ClC6H4 (7i)
c-C6H11 (7j)
15a: 70
15b: 70
15c: 69
15d: 68
15e: 62
15f: 64
15g: 63
15h: 68
91
91
90
90
84
88
86
89
1
2
3
4
5
6
7
COOMe, Et (16a)
COOMe, n-Bu (16b)
COOMe, 2-ClC6H4 (16c)
COOEt, H (16d)
Ac, H (16e)
18a: 74
18b: 72
18c: 68
19a: 76
19b: 73
19c: 76
19d: 75
92
90
88
92
91
92
92
PhCO, H (16f)
CN, H (16g)
a
Resin 13 (prepared from 0.8 g resin 2), aldoxime 7 (5 mmol) N-
a
chlorosuccinimide (NCS, 5 mmol) and Et3N (6 mmol) were heated in
Resin 3 (prepared from 0.8 g resin 2) and 16 (3 mmol) were treated as
35 mL of CH2Cl2 at 35 ꢁC under N2. Isolated yields of crude product conditions in Table 1, run 8. b Isolated yields of crude product 18 or 19
b
c
c
15 based on Br loading of resin 2. Purities of product 15 were based on Br loading of resin 2. Purities of product 18 or 19 were
determined by HPLC analysis.
determined by HPLC analysis.
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derivatives 18 or 19 in good yields and high purities, depending
The reactivities of recovered organoseleno resins were then
on substitutes of the starting materials (Table 5, runs 1–3 vs. 4–7). quantitatively evaluated according to the yields and purities of
compound 6, which was cut down from resin 3. Detailed
experimental procedures and results were depicted in Fig. 1.
The results showed that the yields and purities of 6 were both
high, proving that the organoseleno resins were very much alive
even aer multiple times of recovery and reuse (Fig. 1).13,14
(3)
Conclusions
In conclusion, we developed the practical synthesis for hetero-
cycle-tethered acylbenzofuran derivatives and benzodifurans
using safe, odorless, stable and recyclable organoseleno resin as
polymer carrier. The purication procedures were concise and
the overall product yields and purities were good aer multiple
synthetic steps. The methodology provided a comprehensive
synthesis of acylbenzofurans tethered to versatile heterocycles,
such as isoxazole, triazole and isoxazoline. Besides, unexpected
cyclizations in the syn-seleno elimination step of resin 17
generated interesting benzodifuran derivatives. All of these
analogues are useful for our research projects. The further
investigations on their bioactivities are ongoing in our
laboratory.
To gain more environment-friendly synthetic methodologies
with high resource utilization efficiency, the recycle and reuse of
by-products were our next concern. Besides corresponding
products 9, 12, 15, 18 and 19, all of the above reactions also
generated equivalent by-product 21, a stable organoseleno resin
with a very high molecular weight that might cause waste (eqn
(4)). Fortunately, aer successive treatments with KI, Na2S2O3
and Br2, 21 was easy to be converted to the reusable organo-
seleno resin 2 again, avoiding the generation of massive
amount of solid waste (eqn (5)).13
Experimental section
General methods
(4)
(5)
Chemicals were purchased from reagent merchant and used
without further purication. Polystyrene (H 1000, 100–200
mesh, cross-linked with 1% divinylbenzene, merchant avail-
able) was treated according to reference to prepare organo-
seleno resin 2.15 Reactions were performed under N2 unless
specied. Melting points were measured using a XT-4 binocular
microscope melting point instrument. H NMR and 13C NMR
1
spectra were recorded on a Bruker Avance spectrometer (400
MHz for 1H NMR and 100 MHz for 13C NMR spectroscopy),
using CDCl3 as the solvent and TMS as internal standard. Mass
spectra were recorded on a Bruker Esquire 6000 mass spec-
trometer (ESI). Infrared spectra were recorded on a Bruker
Tensor 27 spectrometer. HPLC was performed on a Waters
e2695 High Performance Liquid Chromatograph (column,
SunFire™ C18 5 mm 4.6 ꢂ 250 mm; mobile phase, THF–MeOH–
H2O, v/v/v 50 : 20 : 30; ow rate, 1.0 mL minꢀ1; Waters 2996
Photodiode Array Detector). HRMS (ESI) were performed on an
Agilent 6210 TOF LC/MS instrument. The samples were further
puried by preparative TLC before NMR analysis.
Typical procedure for the preparation of organoseleno resin 3
(eqn (1))
To a suspension of 0.8 g of organoseleno resin 2 (Br 1.25 mmol
gꢀ1) in 15 mL of CHCl3, 5.0 mol of (3-allyl-5-benzoyl-2,4-dihy-
droxy-phenyl)-phenyl-methanone 1 was added and stirred at
room temperature for 10 min. Then, 3.0 mmol of Et3N was
added and the mixture was stirred at 40 ꢁC for 5 h. The resin was
collected by ltration and washed with H2O (20 mL ꢂ 2), THF
(10 mL ꢂ 2), ethanol (10 mL ꢂ 2), THF–H2O (v/v 2 : 1, 10 mL ꢂ
Fig. 1 Organoseleno resin carrier recovery and reuse.13,14
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2), THF (10 mL ꢂ 2) and CH2Cl2 (10 mL ꢂ 2) successively. The 2), hot DMF (15 mL ꢂ 1), THF (20 mL ꢂ 1), THF–H2O (v/v 2 : 1,
washed wet resin 3 was dried under vacuum overnight before 20 mL ꢂ 2) and THF (20 mL ꢂ 2) successively. Products 12 were
use. The excess starting material 1 could be recollected by then cut down from resins 11 through the similar procedures as
extraction.
the unloading of compound 5.
Typical procedure for the preparation of isoxazoline-tethered
benzofurans 15 (Table 4) and benzodifurans 18 or 19 (Table 5)
Typical procedure for the preparation of organoseleno resin 4
(Table 1, run 8) and compound 5
Resins 13 and 17 were prepared through similar procedures
(eqn (2) and (3)) as preparation of resin 4; Isoxazoline-tethered
benzofurans 15 were prepared from resins 13 (Table 4) through
the similar procedures as the preparation of isoxazole-tethered
benzofurans 9; Benzodifurans 18 or 19 were cut down from
resins 17 (Table 5) through similar procedures as the unloading
of compound 5.
Preparation of resin 4. To a suspension of resin 3 (from 0.8 g
of resin 2) in 15 mL of DMF–CHCl3 (1 : 1), 5 mmol of Et3N and
5 mmol of propargyl bromide were added. The mixture was
stirred at 60 ꢁC for 10 h. The polymer resin was collected by
ltration and washed with H2O (20 mL ꢂ 2), THF (10 mL ꢂ 2),
THF–H2O (v/v 2 : 1, 10 mL ꢂ 2), THF (10 mL ꢂ 2), THF–H2O
(2 : 1, 10 mL ꢂ 2), THF (10 mL ꢂ 2) and CH2Cl2 (10 mL ꢂ 2)
successively. The washed wet resin 4 was dried under vacuum
overnight before use.
Unloading of compound 5. To a suspension of resin 4 in
15 mL of THF, 2.3 g of 30% H2O2 was added and stirred at room
temperature for 3 h. The resin was collected by ltration and
washed with H2O (20 mL ꢂ 2), THF (10 mL ꢂ 2), THF–H2O (v/v
2 : 1, 20 mL ꢂ 2), THF (10 mL ꢂ 2), CH2Cl2 (20 mL ꢂ 2) and
toluene (20 mL ꢂ 2) successively. The washed resin was sus-
pended in 15 mL toluene and stirred with 1.5 mmol of DBU at
80 ꢁC for 5 h. Aer a ltration, the resin 21 was washed with THF
(10 mL), THF–H2O (v/v 2 : 1, 20 mL) and THF (10 mL) subse-
quently and recovered. The solvent THF of the above combined
ltrates was evaporated under vacuum and then dissolved in
10 mL of toluene. The solution was washed with 0.25 M HCl
(30 mL ꢂ 2) and saturated NaHCO3 (35 mL ꢂ 2) and dried with
anhydrous MgSO4. Evaporation of solvent under vacuum
afforded the crude product 5, the purity of which was deter-
mined by HPLC analysis.
Procedure for the regeneration of resin 2 from 21. Recovered
resin 21 (10 g) was rst soaked in dry THF (140 mL) overnight. A
solution of KI (125 mmol) and Na2S2O3 (125 mmol) in 140 mL of
EtOH–H2O (v/v ¼ 1 : 1) was added. The suspension was stirred
gently at room temperature for 12 h. The resin was collected by
ltration and washed with THF (50 mL ꢂ 2), THF–H2O (v/v ¼
1 : 1, 80 mL ꢂ 2), THF (50 mL ꢂ 2). MeOH (50 mL ꢂ 2) and
CH2Cl2 (50 mL ꢂ 2) subsequently and then dried at 40 ꢁC under
vacuum for 6 h. The dried yellow resin was soaked in CHCl3 (100
mL) for 3 h. Bromine (12.5 mmol) was then added dropwisely
over a 20 min interval under ice bath cooling. The mixture was
stirred for 30 min at 0 ꢁC and then poured into a fritted funnel
and the resin was washed thoroughly with MeOH (80 mL ꢂ 2),
CH2Cl2 (80 mL ꢂ 3) and Et2O (80 mL ꢂ 2) subsequently. The
washed yellow resin was then soaked in absolute ethanol (100
mL) and heated to 70 ꢁC for 1 h. The color of the resin became
dark red slowly during this procedure. Aer cooling, the resin
was ltered and washed with EtOH (80 mL ꢂ 1), (80 mL ꢂ 1),
CH2Cl2 (80 mL ꢂ 2) and Et2O (80 mL ꢂ 2) subsequently. The
washed resin was dried under vacuum for 8 h to regenerate the
activated resin 2.
Typical procedure for the preparation of isoxazole-tethered
benzofurans 9 (Table 2)
The reactivity evaluations of the recovered resin 2 were made
according to the yield and purity of compound 6, which was cut
down from resin 3 (prepared from recovered resin 2). The
detailed procedure for the preparation of resin 3 was given in
previous section; the procedure for the unloading of 6 was
similar to that of compound 5, as given in previous section.
Characterization of the products
5 mmol of hydroximoyl chlorides were prepared by stirring 5
mmol of aldoximes 7 and 5 mmol of NCS in 15 mL of CH2Cl2 at
room temperature for 5 h. This hydroximoyl chloride solution
was added to a suspension of resin 4 (from 0.8 g of resin 2) in 10
mL of CH2Cl2. Then, a solution of 6.0 mmol of Et3N in 10 mL of
CH2Cl2 was added dropwisely in 4 h. Aer stirring at 35 ꢁC for 15
h, resins 8 were collected by ltration and washed with H2O (10
mL ꢂ 2), THF (10 mL ꢂ 1), DMF (10 mL ꢂ 1), THF–H2O (v/v
2 : 1, 10 mL ꢂ 2), THF (10 mL ꢂ 2), THF–H2O (v/v 2 : 1, 10 mL ꢂ
2) and THF (10 mL ꢂ 2) successively. Products 9 were then cut
down from resin 8 through the similar procedures as the
unloading of compound 5.
1
Compound 5. Oil; H-NMR (CDCl3): d 7.87 (s, 1H), 7.82–7.80
(m, 2H), 7.70–7.68 (m, 2H), 7.59–7.43 (m, 6H), 6.71 (s, 1H), 4.70
(d, J ¼ 2.8 Hz, 2H), 2.55 (t, J ¼ 2.8 Hz, 1H), 2.47 (s, 3H); 13C-NMR
(CDCl3): d 201.3, 192.0, 161.3, 157.4, 156.5, 138.0, 137.7, 133.3,
132.6, 132.0, 129.7, 129.3, 128.4, 128.2, 120.3, 115.2, 113.2,
100.6, 78.2, 76.3, 60.1, 14.0; MS (ESI) m/z 395 (M + H)+.
Compound 6. White solid, mp: 99–102 ꢁC; 1H-NMR (CDCl3): d
13.30 (s, 1H), 7.85 (s, 1H), 7.80 (d, J ¼ 7.6 Hz, 2H), 7.68 (d, J ¼ 7.2
Hz, 2H), 7.58–7.52 (m, 2H), 7.47–7.42 (m, 4H), 6.70 (s, 1H), 2.45
Typical procedure for the preparation of triazole-tethered
benzofurans 12 (Table 3)
To a suspension of resin 4 (from 0.8 g of resin 2) in 30 mL of (s, 3H); 13C-NMR (CDCl3): d 201.4, 192.4, 161.4, 157.5, 156.6,
DMSO, 4 mmol of CuSO4$5H2O, 4.5 mmol of ascorbic acid (in 138.1, 137.8, 133.2, 132.7, 132.1, 129.8, 129.2, 128.5, 128.2,
10 mL H2O) and 5 mmol of RN3 10 were added. Aer stirring at 120.2, 115.3, 113.2, 100.7, 14.1; MS (ESI) m/z 357 (M + H)+;
60 ꢁC for 15 h, resins 11 were collected by ltration and washed IRnmax (cmꢀ1): 3425, 1634, 1596, 1397, 1289, 1195, 1114, 869,
with H2O (30 mL ꢂ 2), THF (20 mL ꢂ 1), hot DMF (15 mL ꢂ 1), 741, 639; HRMS: m/z calcd for C23H17O4 [M + H]+: 357.1121,
H2O (30 mL ꢂ 1), THF (20 mL ꢂ 1), THF–H2O (v/v 2 : 1, 20 mL ꢂ found: 357.1130.
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Compound 9a. White solid, mp: 91–93 ꢁC; 1H-NMR (CDCl3): d
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H)+; IRnmax (cmꢀ1): 2922, 1658, 1526, 1433, 1237, 1105, 842, 694,
593, 522; HRMS: m/z calcd for C33H23FNO5 [M + H]+: 532.1555,
found: 532.1558.
7.88–7.83 (m, 4H), 7.66–7.55 (m, 5H), 7.49–7.38 (m, 7H), 6.62 (s,
1H), 6.22 (s, 1H), 5.33 (s, 2H), 2.47 (s, 3H); 13C-NMR (CDCl3): d
195.2, 192.5, 167.1, 162.2, 157.5, 155.6, 151.7, 137.8, 137.5,
133.3, 132.9, 131.2, 129.9, 129.4, 128.8, 128.3, 128.1, 127.6,
126.4, 125.4, 125.1, 122.2, 118.2, 101.5, 100.2, 66.1, 14.2; MS
(ESI) m/z 514 (M + H)+; IRnmax (cmꢀ1): 3083, 2982, 2870, 1658,
1594, 1447, 1241, 1109, 738, 692. HRMS (ESI): m/z calcd for
Compound 9g. Pale yellow solid, mp: 125–127 ꢁC; 1H-NMR
(CDCl3): d 8.11 (d, 2H, J ¼ 8.0 Hz), 7.83 (d, 2H, J ¼ 8.0 Hz), 7.71–
7.65 (m, 4H), 7.55–7.32 (m, 7H), 6.64 (s, 1H), 6.28 (s, 1H), 5.32 (s,
2H), 2.45 (s, 3H); 13C-NMR (CDCl3): d 195.2, 192.5, 167.20, 158.2,
156.3, 155.5, 153.0, 148.6, 137.9, 137.8, 135.3, 133.4, 132.9,
130.4, 129.9, 128.6, 128.4, 127.6, 127.6, 125.1, 123.9, 122.1,
118.0, 101.5, 100.7, 66.3, 14.1; MS (ESI) m/z 559 (M + H)+; IRnmax
(cmꢀ1): 3077, 2924, 2848, 1658, 1598, 1521, 1264, 1108, 850;
HRMS: m/z calcd for C33H23N2O7 [M + H]+: 559.1500, found:
559.1510.
C
33H24NO5 [M + H]+: 514.1649, found: 514.1660.
Compound 9b. White solid, mp: 96–98 ꢁC; 1H-NMR (CDCl3): d
7.86–7.82 (m, 4H), 7.60–7.53 (m, 5H), 7.48–7.41 (m, 4H), 7.26–
7.24 (d, J ¼ 8.0 Hz, 2H), 6.64 (d, J ¼ 0.8 Hz, 1H), 6.20 (s, H), 5.32
(s, 2H), 2.46 (d, J ¼ 0.8 Hz, 3H), 2.40 (s, 3H); 13C-NMR (CDCl3): d
195.2, 192.5, 167.2, 162.3, 157.6, 155.7, 151.9, 140.2, 137.8,
137.5, 133.2, 132.9, 129.9, 129.8, 129.5, 128.4, 128.3, 127.8,
126.6, 125.6, 125.0, 122.3, 118.3, 101.4, 100.5, 66.1, 21.3, 14.0;
MS (ESI) m/z 528 (M + H)+; IRnmax (cmꢀ1): 3085, 2920, 1771,
1657, 1595, 1446, 1241, 1106, 801, 693, 642. HRMS (ESI): m/z
calcd for C34H26NO5 [M + H]+: 528.1805, found: 528.1812.
Compound 9c. White solid, mp: 102–104 ꢁC; 1H-NMR (CDCl3):
d 7.88–7.83 (m, 4H), 7.67 (d, 2H, J ¼ 8.8 Hz), 7.62–7.54 (m, 3H),
7.50–7.43 (m, 4H), 6.98 (d, 2H, J ¼ 8.8 Hz), 6.65 (s, 1H), 6.18 (s,
1H), 5.33 (s, 2H), 3.87 (s, 3H), 2.48 (s, 3H); 13C-NMR (CDCl3):
d195.2, 192.5, 167.1, 161.9, 161.0, 157.6, 155.7, 151.9, 137.8,
137.5, 133.2, 132.9, 129.9, 129.8, 128.4, 128.2, 128.1, 127.8,
125.0, 122.3, 121.0, 118.3, 114.2, 101.3, 100.5, 66.1, 55.3, 14.0;
MS (ESI) m/z 544 (M + H)+; IRnmax (cmꢀ1): 2924, 1730, 1653,
1433, 1299, 1247, 1175, 1113, 1030, 797, 699. HRMS: m/z calcd
for C34H26NO6 [M + H]+: 544.1755, found: 544.1765.
Compound 9h. White solid, mp:119–121 ꢁC; 1H-NMR (CDCl3):
d 7.27–7.87 (m, 15H), 6.65 (s, H), 6.12 (s, H), 5.36 (s, 2H), 2.48 (s,
3H), 13C-NMR (CDCl3): d195.07, 192.49, 167.84, 161.10, 157.65,
155.73, 151.69, 137.80, 137.49, 133.26, 132.97, 132.95, 130.43,
130.38, 129.93, 129.84, 129.72, 128.45, 128.26, 127.86, 125.19,
124.96, 122.85, 122.10, 118.34, 101.32, 100.45, 66.0, 14.03; MS
(ESI) m/z 592 (M + H)+, 594 (M + 2 + H)+; IRnmax (cmꢀ1): 3053,
2938, 1657, 1637, 1596, 1395, 1268, 1240, 1176, 980, 790, 731,
693; HRMS: m/z calcd for C33H23BrNO5 [M + H]+: 592.0754,
found: 592.0763.
Compound 9i. Solid, mp: 101–103 ꢁC; 1H-NMR (CDCl3): d
7.88–7.83 (m, 4H), 7.68–7.67 (m, 1H), 7.61–7.54 (m, 3H), 7.49–
7.39 (m, 5H), 7.38–7.34 (m, 2H), 6.64 (s, 1H), 6.49 (s, 1H), 5.34 (s,
2H), 2.47 (s, 3H); 13C-NMR (CDCl3): d195.1, 192.5, 166.7, 161.0,
157.7, 155.6, 151.9, 137.8, 137.6, 133.3, 133.0, 132.8, 131.0,
130.9, 130.4, 130.0, 129.9, 128.4, 128.3, 127.9, 127.8, 127.1,
125.4, 122.9, 118.5, 105.1, 100.5, 66.2, 14.1; MS (ESI) m/z 548 (M
+ H)+, 550 (M + 2 + H)+; IRnmax (cmꢀ1): 3040, 2925, 1655 1638,
1594, 1390, 1253, 1158, 987, 794, 740.; HRMS: m/z calcd for
Compound 9d. White solid, mp: 116–118 ꢁC; 1H-NMR (CDCl3):
d 7.82–7.79 (m, 4H), 7.68 (d, J ¼ 8.4 Hz, 2H), 7.60–7.55 (m, 3H),
7.50–7.43 (m, 6H), 6.64 (s, 1H), 6.21 (s, 1H), 5.33 (s, 2H), 2.46 (s,
3H); 13C-NMR (CDCl3): d 195.1, 192.5, 167.7, 161.3, 157.8, 155.6,
151.9, 137.8, 137.5, 132.2, 133.3, 133.1, 130.0, 129.8, 128.5,
128.4, 128.3, 127.8, 127.3, 125.2, 124.8, 122.2, 118.5, 101.5,
100.3, 66.1, 14.1;MS (ESI) m/z 592 (M + H)+, 594 (M + 2 + H)+;
IRnmax (cmꢀ1): 3082, 2966, 2926, 2862, 1658, 1595, 1427, 1241,
1090, 1012, 851, 694;HRMS: m/z calcd for C33H23BrNO5 [M + H]+:
592.0754, found: 592.0759.
C
33H23ClNO5 [M + H]+: 548.1259, found: 548.1269.
Compound 9j. Solid, mp:70–72 ꢁC; 1H-NMR (CDCl3): d 7.87 (s,
1H), 7.82 (d, J ¼ 7.6 Hz, 2H), 7.70 (d, J ¼ 7.2 Hz, 2H), 7.59–7.54
(m, 2H), 7.49–7.44 (m, 4H), 6.64 (s, 1H), 6.22 (s, 1H), 5.34 (s, 2H),
2.85–2.79 (m, 1H), 2.47 (s, 3H), 2.12–1.30 (m, 10H); 13C-NMR
(CDCl3): d 195.2, 192.4, 167.9, 162.4, 157.7, 155.8, 151.9, 137.8,
137.5, 133.1, 132.9, 130.0, 129.8, 128.4, 128.2, 127.8, 125.1,
122.3, 118.2, 101.4, 100.4, 66.1, 35.3, 31.4, 25.5, 25.3, 14.1; MS
(ESI) m/z 520 (M + H)+; IRnmax (cmꢀ1): 3075, 2933, 2851, 1771,
1657, 1595, 1440, 1241, 1112, 799, 733, 692. HRMS (ESI): m/z
calcd for C33H30NO5 [M + H]+: 520.2118, found: 520.2125.
Compound 9k. Oil; 1H-NMR (CDCl3): d 7.86 (s, 1H), 7.78–7.64
(m, 4H), 7.56–7.51 (m, 2H), 7.50–7.45 (m, 4H), 6.36 (s, 1H), 6.21
(s, 1H), 5.28 (s, 2H), 2.68 (t, J ¼ 7.2 Hz, 2H), 2.45 (s, 3H), 1.68–
1.66 (m, 2H), 1.44–1.40 (m, 2H), 0.90 (t, J ¼ 7.2 Hz, 3H); 13C-
NMR (CDCl3): d 195.2, 192.3, 168.1, 162.6, 157.8, 155.8, 152.0,
138.0, 137.6, 133.3, 133.0, 130.1, 129.7, 128.5, 128.4, 127.7,
125.0, 122.1, 118.3, 101.5, 100.2, 66.0, 30.5, 25.8, 22.3, 14.2, 13.7;
MS (ESI) m/z 494 (M + H)+; IRnmax (cmꢀ1): 3081, 2973, 2969,
2956, 2930, 2880, 1660, 1595, 1239, 1110, 763, 692. HRMS (ESI):
m/z calcd for C31H28NO5 [M + H]+: 494.1962, found: 494.1970.
Compound 9e. White solid, mp: 121–123 ꢁC; 1H-NMR (CDCl3):
d 7.85–7.81 (m, 4H), 7.65–7.54 (m, 5H), 7.48–7.41 (m, 6H), 6.63
(s, 1H), 6.21 (s, 1H), 5.33 (s, 2H), 2.47 (s, 3H); 13C-NMR (CDCl3): d
195.1, 192.5, 167.8, 161.4, 157.7, 155.7, 151.8, 137.8, 137.5,
136.1, 133.2, 133.0, 129.9, 129.8, 129.1, 128.4, 128.3, 128.0,
127.8, 127.0, 125.1, 122.3, 118.4, 101.4, 100.4, 66.1, 14.0;MS
(ESI) m/z 548 (M + H)+, 550 (M + 2 + H)+; IRnmax (cmꢀ1): 2921,
1657, 1596, 1428, 1241, 1092, 1015, 948, 801, 694;HRMS: m/z
calcd for C33H23ClNO5 [M + H]+: 548.1259, found: 548.1265.
Compound 9f. White solid, mp: 114–116 ꢁC; 1H-NMR (CDCl3):
d 7.88–7.83 (m, 4H), 7.73–7.69 (m, 2H), 7.60–7.55 (m, 3H), 7.50–
7.44 (m, 4H), 7.17–7.13 (m, 2H), 6.65 (s, 1H), 6.22 (s, 1H), 5.35 (s,
2H), 2.49 (d, J ¼ 0.8 Hz, 3H), 13C-NMR (CDCl3): d 195.2, 192.6,
167.7, 163.9 (d, J ¼ 248 Hz), 161.5, 157.7, 155.8, 151.9, 137.9,
137.6, 133.3, 133.0, 130.0, 129.9, 128.7 (d, J ¼ 8.3 Hz), 128.5,
128.3, 127.8, 125.2, 124.8 (d, J ¼ 2.5 Hz), 122.5, 118.5, 116.0 (d, J
¼ 22.4 Hz), 115.9, 101.5, 100.5, 66.2, 14.1; MS (ESI) m/z 532 (M +
1
Compound 9l. Oil; H-NMR (CDCl3): d 7.86 (s, 1H), 7.76–7.65
(m, 4H), 7.54–7.50 (m, 2H), 7.48–7.44 (m, 4H), 6.41 (s, 1H), 6.22
(s, 1H), 5.29 (s, 2H), 2.46 (s, 3H), 1.34 (s, 9H); 13C-NMR (CDCl3): d
195.1, 192.5, 168.2, 162.5, 157.7, 155.8, 152.1, 137.9, 137.5,
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133.0, 132.8, 130.0, 129.8, 128.5, 128.3, 127.6, 125.2, 122.2, 2925, 1651, 1600, 1527, 1446, 1348, 1267, 1235, 1107, 1041, 886,
118.1, 101.4, 100.1, 66.1, 32.1, 29.5, 14.1; MS (ESI) m/z 494 (M + 808, 739, 694; HRMS: m/z calcd for C32H22ClN4O6 [M + H]+:
H)+; IRnmax (cmꢀ1): 3086, 3026, 2962, 2943, 2922, 2878, 1660, 593.1222, found: 593.1231.
1591, 1451, 1390, 1370, 1239, 765, 690. HRMS (ESI): m/z calcd
Compound 12g. Solid, mp: 123–125 ꢁC;1H-NMR (CDCl3): d
8.06 (s, 1H), 8.05–7.73 (m, 5H), 7.57–7.55 (m, 2H), 7.51–7.39 (m,
for C31H28NO5 [M + H]+: 494.1962, found: 494.1973.
Compound 12a. White solid, mp: 100–102 ꢁC; 1H-NMR 7H), 6.74 (d, 1H, J ¼ 1.2 Hz), 5.48 (s, 2H), 2.46 (s, 3H); 13C-NMR
(CDCl3): d 7.86–7.81 (m, 4H), 7.62–7.39 (m, 13H), 6.79 (d, 1H, J ¼ (CDCl3): d 195.7, 192.9, 157.8, 156.2, 152.5, 144.7, 144.6, 138.3,
0.4 Hz), 5.50 (s, 2H), 2.47 (s, 3H); 13C-NMR (CDCl3): d 195.7, 138.0, 137.2, 134.1, 133.4, 133.2, 130.3, 130.2, 129.2, 128.8,
192.9, 157.6, 156.3, 152.7, 144.5, 138.4, 138.0, 137.1, 133.3, 128.7, 128.6, 128.1, 126.1, 125.2, 124.7, 122.4, 118.3, 101.2, 67.1,
133.1, 130.2, 130.1, 129.9, 129.1, 128.7, 128.6, 128.2, 125.0, 14.3; MS (ESI) m/z 593 (M + H)+; IRnmax (cmꢀ1): 3065, 1657, 1596,
122.0, 121.1, 120.7, 118.2, 101.4, 67.3, 14.3; MS (ESI) m/z 514 (M 1543, 1447, 1351, 1242, 1177, 1109, 1041, 881, 695; HRMS: m/z
+ H)+; IRnmax (cmꢀ1): 3058, 1656, 1596, 1446, 1240, 1106, 1044, calcd for C32H22ClN4O6 [M + H]+: 593.1222, found: 593.1225.
873, 760, 691; HRMS: m/z calcd for C32H24N3O4 [M + H]+:
514.1761, found: 514.1755.
Compound 12h. Solid, mp: 118–120 ꢁC; 1H-NMR (CDCl3): d
7.84–7.78 (m, 4H), 7.66 (d, 2H, J ¼ 5.6 Hz), 7.56–7.38 (m, 8H),
Compound 12b. Solid, mp: 112–114 ꢁC; 1H-NMR (CDCl3): d 6.74 (d, 1H, J ¼ 1.2 Hz), 5.48 (s, 2H), 2.46 (s, 3H); 13C-NMR
7.86–7.81 (m, 4H), 7.67–7.63 (m, 2H), 7.58–7.40 (m, 10H), 6.77 (CDCl3): d 195.6, 192.9, 157.7, 156.1, 152.5, 144.0, 138.3, 138.0,
(s, 1H), 5.50 (s, 2H), 2.48 (s, 3H); 13C-NMR (CDCl3): d 195.3, 135.1, 133.9, 133.4, 133.2, 132.6, 132.0, 130.2, 130.2, 129.0,
192.6, 157.3, 152.3, 151.8, 144.5, 138.0, 137.6, 133.0, 132.8 128.7, 128.6, 128.1, 127.3, 125.2, 125.0, 122.4, 118.3, 101.2, 67.1,
(3),132.7 (7), 132.6, 129.9, 129.8, 129.7, 128.4, 128.2, 127.90, 14.4; MS (ESI) m/z 616 (M + H)+; IRnmax (cmꢀ1): 3059, 1657, 1595,
124.7, 122.4, 121.7, 121.2, 120.6, 100.9, 66.9, 14.0; MS (ESI) m/z 1482, 1241, 1176, 1105, 1042, 882, 798, 695; HRMS: m/z calcd for
592 (M + H)+, 594 (M + 2 + H)+; IRnmax (cmꢀ1): 2921, 1656, 1595,
1498, 1446, 1241, 1176, 1107, 987, 827, 695; HRMS: m/z calcd for
C
32H21Cl3N3O4 [M + H]+: 616.0592, found: 616.0601.
Compound 12i. Oil; 1H-NMR (CDCl3): d 7.87–7.80 (m, 4H),
C
32H23BrN3O4 [M + H]+: 592.0866, found: 592.0868.
7.70–7.66 (m, 2H), 7.60–7.48 (m, 6H), 6.76 (s, 1H), 5.52 (s, 2H),
Compound 12c. Solid, mp: 102–104 ꢁC; 1H-NMR (CDCl3): d 4.98 (m, 1H), 2.46 (s, 3H), 1.30 (d, J ¼ 4.0 Hz, 6H); 13C-NMR
8.78–8.76 (d, 2H, J ¼ 5.6 Hz), 7.85–7.81 (m, 4H), 7.64–7.40 (m, (CDCl3): d 195.5, 192.6, 157.0, 152.2, 144.3, 138.0, 133.3, 132.6,
10H), 6.77 (d, 1H, J ¼ 0.8 Hz), 5.52 (s, 2H), 2.47 (s, 3H); 13C-NMR 132.2, 130.0, 129.6, 129.1, 128.7, 128.5, 128.1, 126.9, 125.3,
(CDCl3): d 195.6, 192.8, 157.7, 156.2, 152.5, 151.9, 145.4, 143.1, 122.4, 118.8, 101.1, 66.7, 58.7, 21.6, 21.5, 14.1; MS (ESI) m/z 480
138.4, 137.9, 133.4, 133.2, 130.3, 130.2, 128.7, 128.6, 128.1, (M + H)+; IRnmax (cmꢀ1): 3081, 2967, 2923, 2876, 2851, 1656,
125.0, 122.1, 120.5, 118.3, 113.9, 101.2, 67.1, 14.3; MS (ESI) m/z 1596, 1449, 1380, 1370, 1109, 768, 691; HRMS (ESI): m/z calcd
515 (M + H)+; HRMS: m/z calcd for C31H23N4O4 [M + H]+: for C29H26N3O4 [M + H]+: 480.1918, found: 480.1912.
515.1714, found: 515.1723.
Compound 15a. Solid, mp: 98–100 ꢁC; 1H-NMR (CDCl3): d 7.86
Compound 12d. Solid, mp: 105–107 ꢁC; 1H-NMR (CDCl3): d (d, 2H, J ¼ 7.2 Hz), 7.80 (d, 2H, J ¼ 8.0 Hz), 7.60–7.51 (m, 3H),
7.84–7.79 (m, 4H), 7.57–7.53 (m, 2H), 7.47–7.28 (m, 9H), 7.19– 7.48–7.40 (m, 6H), 7.21 (d, 2H, J ¼ 8.0 Hz), 6.70 (s, 1H), 4.79–4.75
7.16 (m, 1H), 6.77 (s, 1H), 5.48 (s, 2H), 2.44 (s, 3H), 2.10 (s, 3H); (m, 1H), 4.37–4.26 (m, 2H), 3.20–3.13 (m, 1H), 2.99–2.93 (m,
13C-NMR (CDCl3): d 195.7, 192.9, 157.5, 156.2, 152.8, 143.6, 1H), 2.45 (s, 3H), 2.39 (s, 3H); 13C-NMR (CDCl3): d 195.5, 192.7,
138.4, 138.0, 136.5, 133.8, 133.3, 133.2, 131.7, 130.2, 130.14, 157.1, 156.3, 155.9, 152.8, 140.4, 138.0, 137.7, 133.1, 132.8,
130.10, 128.7, 128.6, 128.2, 127.0, 126.1, 125.2, 124.7, 122.4, 130.0, 129.7, 129.3, 128.4, 128.3, 128.0, 126.70, 126.68, 124.4,
118.2, 101.4, 67.4, 18.0, 14.3; MS (ESI) m/z 528 (M + H)+;IRnmax 121.9, 117.7, 101.0, 78.4, 73.3, 36.8, 21.4, 14.1. MS (ESI) m/z 529
(cmꢀ1): 3058, 1656, 1595, 1446, 1238, 1105, 1043, 985, 872, 762, (M + H)+; IRnmax (cmꢀ1): 2924, 1658, 1597, 1447, 1247, 1109, 897,
694; HRMS: m/z calcd for C33H26N3O4 [M + H]+: 528.1918, found: 695; HRMS: m/z calcd for C34H28NO5 [M + H]+: 530.1962, found:
528.1925.
Compound 12e. Solid, mp: 116–118 ꢁC; 1H-NMR (CDCl3): d
530.1969.
Compound 15b. Solid, mp: 107–109 ꢁC; 1H-NMR (CDCl3): d
7.86–7.80 (m, 4H), 7.58–7.55 (m, 4H), 7.51–7.34 (m, 7H), 6.76 (d, 7.85 (d, 2H, J ¼ 7.6 Hz), 7.79 (d, 2H, J ¼ 7.2 Hz), 7.57–7.38 (m,
1H, J ¼ 0.4 Hz), 5.50 (s, 2H), 2.48 (d, 3H, J ¼ 1.2 Hz); 13C-NMR 9H), 6.92 (d, 2H, J ¼ 8.8 Hz), 6.70 (s, 1H), 4.80–4.72 (m, 1H),
(CDCl3): d 195.6, 192.9, 157.6, 156.2, 152.6, 143.9, 138.3, 138.0, 4.37–4.26 (m, 2H), 3.85 (s, 3H), 3.19–3.08 (m, 1H), 2.98–2.88 (m,
135.5, 133.9, 133.4, 133.2, 131.9, 131.1, 130.3, 130.2, 128.7, 1H), 2.45 (s, 3H); 13C-NMR (CDCl3): d 195.5, 192.7, 161.1, 157.1,
128.6, 128.2, 127.9, 127.0, 125.2, 125.1, 122.4, 118.3, 101.3, 67.2, 155.9, 152.8, 138.0, 137.7, 133.1, 132.8, 129.9, 129.8, 129.7,
14.4; MS (ESI) m/z 582 (M + H)+; IRnmax (cmꢀ1): 2922, 1657, 1595, 128.33, 128.27, 128.24, 128.0, 124.4, 121.8, 121.6, 117.7, 114.0,
1446, 1241, 1100, 1041, 879, 811, 604; HRMS: m/z calcd for 101.0, 78.3, 73.3, 55.3, 37.0, 14.1. MS (ESI) m/z 545 (M + H)+;
C
32H22Cl2N3O4 [M + H]+: 582.0982, found: 582.0980.
IRnmax (cmꢀ1): 2962, 2924, 1658, 1260, 1100, 1024, 803, 696;
Compound 12f. Solid, mp: 120–122 ꢁC; 1H-NMR (CDCl3): d HRMS: m/z calcd for C34H28NO6 [M + H]+: 546.1911, found:
8.47 (s, 1H), 8.467–8.30 (m, 1H), 7.86–7.80 (m, 5H), 7.77 (s, 1H), 546.1903.
7.58–7.39 (m, 7H), 6.76 (s, 1H), 5.51 (s, 2H), 2.48 (s, 3H); 13C-
Compound 15c. Solid, mp: 109–111 ꢁC; 1H-NMR (CDCl3): d
NMR (CDCl3): d 195.3, 192.5, 157.4, 155.8, 152.1, 148.0, 144.0, 7.80 (d, 2H, J ¼ 7.2 Hz), 7.73 (d, 2H, J ¼ 7.2 Hz), 7.55–7.30 (m,
139.2, 137.8, 137.6, 133.1, 132.9, 129.9, 129.86, 128.9, 128.3, 11H), 6.65 (s, 1H), 4.80–4.76 (m, 1H), 4.31 (d, 2H, J ¼ 4.4 Hz),
128.2, 128.1, 127.7, 126.3, 124.9, 124.6, 123.0, 122.2, 118.0, 3.16–3.09 (m, 1H), 2.97–2.92 (m, 1H), 2.40 (s, 3H); 13C-NMR
100.8, 66.8, 14.0; MS (ESI) m/z 593 (M + H)+; IRnmax (cmꢀ1): 3057, (CDCl3): d 195.3, 192.6, 157.1, 155.8, 155.4, 152.6, 137.9, 137.6,
49176 | RSC Adv., 2014, 4, 49170–49179
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Compound 18a. Solid, mp: 140–141 ꢁC; 1H-NMR (CDCl3): d
7.86–7.84 (m, 4H), 7.60–7.53 (m, 3H), 7.47–7.41 (m, 4H), 6.53 (s,
1H), 4.88 (t, J ¼ 5.2 Hz, 1H), 3.62 (s, 3H), 2.45 (s, 3H), 1.77–1.68
(m, 2H), 0.69 (t, J ¼ 7.6 Hz, 3H); 13C NMR (CDCl3): d 195.0, 192.0,
170.3, 156.5, 155.4, 151.4, 137.7, 137.4, 132.5, 132.3, 129.4,
127.9, 127.8, 127.7, 124.3, 120.6, 120.5, 117.2, 100.4, 80.5, 51.6,
25.7, 13.5, 8.1. MS (ESI) m/z 457 (M + H)+; IRnmax (cmꢀ1): 3444,
3058, 2971, 2949, 2879, 1755, 1664, 1600, 1355, 1262, 1214,
1180, 1102, 1084, 956, 933, 792, 737, 708, 637, 551; HRMS: m/z
calcd for C28H25O6 [M + H]+: 457.1646, found: 457.1642.
Compound 18b. Solid, mp: 124–126 ꢁC; 1H-NMR (CDCl3): d
7.85–7.84 (m, 4H), 7.60 (s, 1H), 7.57–7.53 (m, 2H), 7.47–7.42 (m,
4H), 6.51 (s, 1H), 4.91 (d, J ¼ 4.0 Hz, 1H), 3.62 (s, 3H), 2.45 (s,
3H), 1.71–1.63 (m, 2H), 1.14–1.11 (m, 2H), 1.04–1.01 (m, 2H),
0.76 (t, J ¼ 6.9 Hz, 3H); 13C NMR (CDCl3): d 195.6, 192.7, 171.1,
156.9, 155.9, 151.8, 138.1, 137.8, 132.9, 132.8, 129.98, 129.92,
128.4, 128.3, 128.2, 124.6, 120.98, 117.7, 100.7, 80.2, 52.1, 32.6,
26.3, 22.2, 14.1, 13.7; MS (ESI) m/z 485 (M + H)+; IRnmax (cmꢀ1):
3452, 3056, 2953, 2921, 2861, 1754, 1667, 1598, 1448, 1329,
1264, 1209, 1099, 1046, 950, 792, 763, 737, 706, 639, 529. HRMS:
m/z calcd for C30H29O6 [M + H]+: 485.1959, found: 485.1966.
Compound 18c. Solid, mp: 65–67 ꢁC; 1H-NMR (CDCl3): d7.84–
7.79 (m, 4H), 7.64 (s, 1H), 7.56–7.48 (m, 2H), 7.44–7.36 (m, 4H),
7.29–7.27 (m, 1H), 7.20–7.15 (m, 1H), 7.06–7.03 (m, 1H), 6.91–
6.89 (m, 1H), 6.50 (d, J ¼ 1.2 Hz, 1H), 6.30 (s, 1H), 3.57 (s, 3H),
2.41 (s, 3H); 13C NMR (CDCl3): d 195.1, 192.6, 168.6, 157.4,
155.8, 150.9, 138.1, 137.5, 132.84, 132.76, 132.68, 130.13,
129.91, 129.84, 129.34, 128.74, 128.31, 128.22, 128.10, 127.1,
125.4, 121.8, 118.4, 100.3, 78.6, 52.6, 14.0. MS (ESI) m/z 539 (M +
H)+; IRnmax (cmꢀ1): 3441, 3056, 2963, 2246, 1652, 1598, 1473,
1427, 1191, 1087, 1021 , 942, 907, 860, 844, 804, 763, 690, 583,
531. HRMS: m/z calcd for C32H24ClO6 [M + H]+: 539.1256, found:
539.1249.
136.0, 133.0, 132.8, 129.9, 129.7, 128.8, 128.3, 128.2, 127.91,
127.87, 127.6, 124.4, 121.8, 117.7, 100.9, 78.9, 73.3, 36.3, 14.0;
MS (ESI) m/z 549 (M + H)+; IRnmax (cmꢀ1): 2923, 1658, 1597,
1474, 1260, 1093, 827, 660.; HRMS: m/z calcd for C33H25ClNO5
[M + H]+: 550.1416, found: 550.1420.
Compound 15d. Solid, mp: 108–110 ꢁC; 1H-NMR (CDCl3): d
7.83 (d, 2H, J ¼ 7.2 Hz), 7.77 (d, 2H, J ¼ 7.2 Hz), 7.58–7.35 (m,
9H), 7.08–7.04 (m, 2H), 6.68 (s, 1H), 4.82–4.78 (m, 1H), 4.34–4.32
(d, 2H), 3.19–3.12 (m, 1H), 3.01–2.95 (m, 1H), 2.43 (s, 3H); 13C-
NMR (CDCl3): d 195.3, 192.6, 163.7 (d, J ¼ 248.9 Hz), 157.1,
155.9, 155.4, 152.7, 137.9, 137.6, 133.1, 132.8, 129.9, 129.7, 128.6
(d, J ¼ 8.4 Hz), 128.3, 128.2, 127.9, 125.3 (d, J ¼ 3.4 Hz), 124.4,
121.8, 117.7, 115.7 (d, J ¼ 21.5 Hz), 100.9, 78.7, 73.2, 36.6, 14.0;
MS (ESI) m/z 533 (M + H)+; IRnmax (cmꢀ1): 3059, 2920, 1658,
1596, 1446, 1259, 875, 759, 695; HRMS: m/z calcd for
C
33H25FNO5 [M + H]+: 534.1711, found: 534.1722.
Compound 15e. Solid, mp: 112–114 ꢁC; 1H-NMR (CDCl3): d
8.21 (d, 2H, J ¼ 8.8 Hz), 7.81 (d, 2H, J ¼ 8.0 Hz), 7.72–7.67 (m,
4H), 7.56–7.32 (m, 7H), 6.65 (s, 1H), 4.93–4.89 (m, 1H), 4.42–4.33
(d, 2H), 3.25–3.08 (m, 2H), 2.43 (s, 3H); 13C-NMR (CDCl3): d
195.2, 192.6, 157.4, 155.9, 155.0, 152.5, 148.5, 137.8, 137.7,
135.2, 133.2, 132.9, 130.0, 129.9, 128.4, 128.3, 127.8, 127.5,
124.6, 123.8, 122.0, 117.9, 100.8, 79.9, 73.3, 35.9, 14.1; MS (ESI)
m/z 561 (M + H)+; IRnmax (cmꢀ1): 2962, 1658, 1598, 1519, 1261,
1104, 1028, 802; HRMS: m/z calcd for C33H25N2O7 [M + H]+:
561.1656, found: 561.1649.
Compound 15f. Solid, mp: 101–103 ꢁC; 1H-NMR (CDCl3): d
7.81–7.79 (m, 2H), 7.74–7.72 (m, 2H), 7.59–7.34 (m, 10H), 7.32–
7.19 (m, 1H), 6.67 (s, 1H), 4.82–4.77 (m, 1H), 4.32 (d, 2H, J ¼ 4.4
Hz), 3.12–3.05 (m, 1H), 2.88–2.82 (m, 1H), 2.40 (s, 3H); 13C-NMR
(CDCl3): d 195.3, 192.5, 157.1, 155.8, 155.2, 152.6, 137.8, 137.6,
133.1, 132.8, 131.1, 130.1, 129.9, 129.7, 129.6, 128.3, 128.2,
128.1, 127.9, 125.2, 124.4, 122.6, 121.7, 117.7, 100.9, 79.0, 73.1,
36.0, 14.0; MS (ESI) m/z 593 (M + H)+; IRnmax (cmꢀ1): 2921, 1658,
1596, 1244, 910, 873, 786, 690; HRMS: m/z calcd for
Compound 19a. Solid, mp: 111–114 ꢁC; 1H-NMR (CDCl3): d
7.85–7.83 (m, 2H), 7.64 (s, 1H), 7.58–7.56 (m, 3H), 7.48–7.45 (m,
5H), 6.86 (s, 1H), 4.38–4.33 (q, J ¼ 6.8 Hz, 2H), 2.48 (s, 3H), 1.28
(t, J ¼ 6.8 Hz, 3H); 13C-NMR (CDCl3): d 193.7, 159.7, 157.2, 153.4,
148.8, 140.4, 137.8, 132.9, 130.47, 130.31, 130.14, 130.0, 128.58,
128.24, 128.17, 122.8, 120.8, 118.9, 115.7, 99.6, 61.3, 29.7, 14.1;
MS (ESI) m/z 425 (M + H)+; IRnmax (cmꢀ1): 3058, 2971, 2949,
2879, 1755, 1664, 1600, 1355, 1262, 1214, 1180, 1102, 1084, 956,
933, 792, 737, 708, 637, 551; HRMS: m/z calcd for C27H21O5 [M +
H]+: 425.1384, found: 425.1391.
C
33H25BrNO5 [M + H]+: 594.0911, found: 594.0906.
Compound 15g. Solid, mp: 94–96 ꢁC; 1H-NMR (CDCl3): d 7.82
(d, 2H, J ¼ 7.6 Hz), 7.74 (d, 2H, J ¼ 7.2 Hz), 7.56–7.21 (m, 11H),
6.71 (s, 1H), 4.80–4.76 (m, 1H), 4.30 (d, 2H, J ¼ 4.8 Hz), 3.37–3.30
(m, 1H), 3.04–2.98 (m, 1H), 2.39 (s, 3H); d13C-NMR (CDCl3): d
195.3, 192.6, 157.1, 156.2, 155.8, 152.8, 137.9, 137.6, 133.2,
133.1, 132.8, 132.6, 130.8, 130.5, 130.4, 129.9, 129.6, 128.5,
128.4, 128.3, 128.2, 127.9, 126.8, 124.5, 121.9, 177.7, 101.0, 79.1,
73.3, 38.9, 14.0; MS (EI) m/z 549 (M + H)+; IRnmax (cmꢀ1): 2926,
1654, 1599, 1232, 1112, 837, 736, 682; HRMS: m/z calcd for
Compound 19b. Solid, mp: 119–122 ꢁC; 1H-NMR (CDCl3): d
7.85–7.83 (m, 2H), 7.62–7.56 (m, 4H), 7.50–7.44 (m, 5H), 6.85 (s,
1H), 2.49 (s, 6H); 13C-NMR (CDCl3): d 193.5, 188.8, 157.3, 153.7,
148.4, 147.6, 137.6, 133.0, 130.31, 130.06, 129.8, 129.0, 128.9,
128.6, 128.2, 123.1, 120.8, 119.3, 115.5, 99.4, 28.3, 14.2.; MS (ESI)
m/z 395 (M + H)+; IRnmax (cmꢀ1): 3060, 1665, 1632, 1447, 1358,
1293, 1257, 1214, 1096, 935, 871, 802, 762, 738, 693, 607; HRMS:
m/z calcd for C26H19O4 [M + H]+: 395.1278, found: 395.1273.
Compound 19c. Solid, mp: 123–125 ꢁC; 1H-NMR (CDCl3): d
7.88–7.84 (m, 4H), 7.76 (s, 1H), 7.62–7.59 (m, 1H), 7.49–7.44 (m,
5H), 7.35–7.31 (m, 5H), 6.85 (s, 1H), 2.50 (s, 3H); 13C-NMR
(CDCl3): d 193.58, 185.31, 157.32, 153.69, 148.97, 147.51, 137.87,
137.20, 133.00, 132.58, 130.81, 130.54, 130.13, 130.00, 129.76,
C
33H25ClNO5: 550.1416, found: 550.1425.
Compound 15h. Oil; 1H-NMR (CDCl3): d 7.86 (s, 1H), 7.79–7.72
(m, 4H), 7.60–7.45 (m, 6H), 6.72 (s, 1H), 4.78–4.74 (m, 1H), 4.36–
4.25 (m, 2H), 3.19–3.12 (m, 1H), 2.98–2.92 (m, 1H), 2.84–2.77
(m, 1H), 2.44 (s, 3H), 2.13–1.31 (m, 10H); 13C-NMR (CDCl3): d
195.4, 192.6, 157.1, 156.3, 155.9, 152.8, 137.8, 137.5, 133.0,
132.5, 130.2, 129.2, 128.5, 127.9, 126.7, 124.8, 122.1, 118.1,
101.7, 78.6, 73.3, 37.2, 35.4, 31.5, 25.5, 25.4, 14.1. MS (ESI) m/z
522 (M + H)+; IRnmax (cmꢀ1): 3075, 2928, 2852, 1659, 1596, 1446,
1375, 1247, 1110, 768, 690; HRMS (ESI): m/z calcd for C33H32NO5
[M + H]+: 522.2275, found: 522.2281.
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128.50, 128.42, 128.26, 128.04, 122.62, 121.02, 119.13, 115.75,
99.54, 14.20; MS (ESI) m/z 457 (M + H)+; IRnmax (cmꢀ1): 2921,
1634, 1596, 1470, 1445, 1398, 1362, 1290, 1195, 1178, 1115,
1068, 1027, 927, 755, 743, 699; HRMS: m/z calcd for C31H21O4 [M
+ H]+: 457.1434, found: 457.1441.
J. A. Pfefferkorn, H. J. Mitchell, A. J. Roecker, S. Barluenga,
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Compound 19d. Solid, mp: 127–130 ꢁC; 1H-NMR (CDCl3): d
7.88–7.87 (m, 2H), 7.86–7.81 (m, 2H), 7.77–7.71 (m, 1H), 7.60–
7.54 (m, 3H), 7.50–7.46 (m, 3H), 6.80 (s, 1H), 2.51 (s, 3H); 13C-
NMR (CDCl3): d 193.3, 157.9, 153.6, 149.8, 137.9, 137.5, 133.2,
130.1, 129.7, 129.4, 129.0, 128.4, 128.3, 128.1, 123. 6, 121.4,
118.2, 115.2, 113.0, 100.6, 14.2; MS (ESI) m/z 378 (M + H)+;
IRnmax (cmꢀ1): 3028, 2920, 2222, 1658, 1598, 1445, 1394, 1288,
1257, 1177, 1112, 1076, 762, 732, 696; HRMS: m/z calcd for
C
25H16NO3 [M + H]+: 378.1125, found: 378.1120.
Acknowledgements
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This work was supported by NNSFC (21202141, 21202151 and
20902070), ZJNSF for Distinguished Young Scholars
(R14B020009), ZJNSF (Y4090410), Science and Technology
Department of Zhejiang Province Foundation of China
(2010C32022), and 580 Oversea Talents Program of Wenzhou
City. We also thank Jiangsu Yangnong Chemical Group Co. Ltd.
for nancial support, analysis centre of Yangzhou University for
assistances and Dr Lei Zhu (associate professor in the depart-
ment of chemistry and biochemistry at Florida State University,
US) for advises.
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Green Chem., 2014, 16, 287; (f) H.-N. Chen, W.-J. Dai,
Y. Chen, Q. Xu, J.-H. Chen, L. Yu, Y.-J. Zhao, M.-D. Ye and
Y.-J. Pan, Green Chem., 2014, 16, 2136; (g) L. Yu, J. Wang,
Table 1), the resin was ltered and recycled. Filtrate
containing compound 5 was evaporated under vacuum
and the residue was weighted directly to calculate the yield
of crude 5. The purity of 5 was determined by HPLC.
X. Zhang, H.-E. Cao, G.-L. Wang, K.-H. Ding, Q. Xu and 13 For details please see Experimental section.
M. Lautens, RSC Adv., 2014, 4, 19122; (h) L. Yu, J. Wang, 14 For detailed table please see ESI†
H.-E. Cao, K.-H. Ding and Q. Xu, Chin. J. Org. Chem., 2014, 15 K. C. Nicolaou, J. Pastor, S. Barluenga and N. Winssinger,
DOI: 10.6023/cjoc201405004; (i) L. Yu, Y.-L. Wu, T. Chen,
Y. Pan and Q. Xu, Org. Lett., 2013, 15, 144; (j) L. Yu, Mini-
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