Directing-group-assisted copper-catalyzed oxidative esterification of phenols with aldehydes

Article abstract of DOI:10.1039/c5ob01465d

A directing-group-assisted copper-catalyzed oxidative esterification of phenols with aldehydes using TBHP as an oxidant was described. This methodology which showed the advantages of base, ligand free, short routes and functional group tolerance could be used as an alternative protocol for the classical esterification reactions.

Full text of DOI:10.1039/c5ob01465d

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DOI: 10.1039/C5OB01465D
Directing-Group-Assisted
Copper-Catalyzed
Oxidative Esterfication of Phenols with Aldehydes
Yong Zheng†, Wei-Bin Song†, and Li-Jiang Xuan*
Affiliation
State Key Laboratory of Drug Research, Shanghai Institute of Materia
Medica, Chinese Academy of Sciences, 501 Haike Road, Zhangjiang
Hi-Tech Park, Shanghai 201203, PR China
†These authors contributed equally to this work.
* Corresponding to: Li-Jiang Xuan; Tel: +86-21-20231968, Fax:
+86-21-20231968, E-mail address: ljxuan@mail.shcnc.ac.cn.
1

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Abstract
A directing-group-assisted copper-catalyzed oxidative esterification of phenols with
aldehydes using TBHP as oxidant was described. This methodology which showed
the advantages of base, ligand free, short routes and functional group tolerance, could
be used as an alternative protocol for the classical esterification reactions.
2

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DOI: 10.1039/C5OB01465D
Introduction
As is well known, esters are not only important building blocks in natural
products and bioactive compounds such as anti-inflammatory, analgesic,[1]
antimycobacterium,[2] tryptase inhibitor,[3] and antimicrobial agent,[4] Hsp90
modulator or inhibitor,[5] as well as GLYT1 inhibitor (Figure 1),[6] but are also used
as protecting groups in organic synthesis.[7,8] Thus, the construction of ester groups
have always been synthetically attractive.
Figure 1. Bioactive compounds containing ester moieties.
Traditionally, the preparation of ester groups mainly relied on the nucleophilic
addition of alcohols to activated carboxylic acid derivatives, such as acid anhydrides
or chlorides in the presence of a stoichiometric amount of bases.[7b] An alternative
route involved transition-metal-catalyzed carbonylative coupling reactions between
aryl halides and alcohols.[9] However，drawbacks such as utilization of base, air and
moisture-sensitive acyl halides, and toxic CO gas have restricted the practicality of
these reactions. Therefore, developing new environmentally friendly, atom-efficient
methods for the preparation of ester groups are highly desirable.
Recently, the transition metal-catalyzed direct C−H functionalization is emerging
as
a
very powerful tool in organic chemistry,[10] among which the
3

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cross-dehydrogenative coupling (CDC) reaction have been highly developed in more
recent years for the direct generation of C−C, C−O, C−N, and C−S bonds with the
advantages of avoiding prefunctionalized starting materials, step economy and atom
economy.[11,12] For example, NHC ligands combined with Pd or Fe catalysts were
developed for the construction of ester groups by directly oxidative esterification of
phenols with aldehydes.[13] However, the use of these ligands itself involved a
multistep synthesis and moreover, poor yields were obtained for the ortho-substituted
phenols which decreased the efficiency of these reactions.
It is worthy to note that copper is classified as an ideal catalyst in view of green
and sustainable chemistry, owing to its abundant, cheap, and environmental friendly
characters.[14] More remarkable, Cu-catalyzed directing-groups-assisted CDC reaction
under oxidative conditions have provided an atom-economic route for the
esterification of 2-carbonyl phenol with β-dicarbonyl compounds (Scheme 1). In 2006,
Li developed copper-catalyzed oxidative esterification of aldehydes with β-dicarbonyl
compounds using tert-butyl hydroperoxide (TBHP) as the oxidant.[15a] Reddy and
Chang reported the copper-catalyzed synthesis of carbamates by reacting
β-dicarbonyl- or 2-carbonyl phenols with N,N’-disubstituted formamides.[15b-15d] In
2013, Patel achieved Cu-catalyzed esterification of 2-carbonyl phenols and
β-dicarbonyl compounds with toluene derivatives.[15e] Later, Kim reported
copper-catalyzed oxidative esterification of 2-carbonyl phenols with alcohols or
ethers.[15f-15g] Obviously, those substrate scopes were limited to 2-carbonyl phenol or
β-dicarbonyl compounds. Considering the coordination ability of carbonyl
functionality and N-atom with copper metal, we aimed to extend the scope of
directing-groups (DGs) in the copper-catalyzed oxidative esterification of phenols.
Herein we wish to report a copper-catalyzed oxidative esterification of phenols using
cyano, azo, and pyridine as the directing groups (Scheme 1).
4

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Scheme 1. Cu-catalyzed directing-groups-assisted CDC reactions
Results and discussion
Our initial investigation began with esterification of salicylanilide (1a) (0.5
mmol) with benzaldehyde (2a) (0.5 mL) in DMSO in the presence of 10 mol %
Cu(OAc)2 and 70% aq. TBHP (1.5 equiv.) at 90°C for 10 h (Table 1, entry 1). As
expected, the desired product 3a was obtained in 37% yield. Other Cu catalysts, such
as CuCl2·2H2O, CuCl, CuBr, and CuI did not give any improvement (Table 1, entries
2-5). When the oxidant TBHP was changed to di-tert-butyl peroxide (DTBP), O2,
H2O2, and mCPBA, we found these oxidants were not effective (Entries 6-9). When 3
equiv of TBHP was loaded, the yield of 3a increased to 75% (Entry 10). Other
solvents, such as PhCl, toluene, and DCE, were proved to be less efficient than
DMSO (Entries 11-13). Higher or lower temperatures seemed to be inappropriate for
the reaction (Entries 14 and 15). Furthermore, the reaction did not proceed without
using of Cu catalyst or TBHP (Entries 16 and 17).
Table1. Optimization of reaction conditionsa
5

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Entry Catalyst
Oxidant
(equiv.)
Solvent
Yield
(%)b
37
30
28
31
38
15
0
1
2
3
Cu(OAc)2
CuCl2·2H2O
CuCl
TBHP (1.5)
TBHP (1.5)
TBHP (1.5)
TBHP (1.5)
TBHP (1.5)
DTBP (1.5)
O2
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
4
CuBr
5
CuI
6
7
8
9
10
11
12
13
14c
15d
16
17
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
-
H2O2 (1.5)
mCPBA (1.5) DMSO
13
0
TBHP (3)
TBHP (3)
TBHP (3)
TBHP (3)
TBHP (3)
TBHP (3)
TBHP (3)
-
DMSO
PhCl
Toluene
DCE
DMSO
DMSO
DMSO
DMSO
75
59
36
47
34
72
0
Cu(OAc)2
0
[a] Conditions: 1 (0.5 mmol), 2 (0.7 mmol), catalyst (10 mol-%), oxidant, solvent (2 mL), 90 °C,
10h. [b] Isolated yield. [c] 60 °C. [d] 100 °C.
Basing on the established standard reaction conditions, we further investigated
the scope of the reaction using salicylanilide and several substituted benzaldehydes
(Table 2). In general, the reactions between salicylanilides and benzaldehydes
substituted with electron-donating groups (Me, OMe) on the aromatic ring gave
moderate to good yields (3b, 3d, 3f), while weakly electron-withdrawing groups (F,
Br, Cl) on the aromatic resulted in decreased yields (3c, 3e, 3g). Meanwhile, the
ortho-substituted toluenes gave slightly poorer yields of the corresponding products
possibly due to their steric hindrance (3g). Heteroaryl aldehydes, such as
2-thiophenaldehyde, could also react with salicylanilide smoothly and afford the
desired products in 73% yield (3h). Particularly, this process was tolerated by halogen
groups which could be used as versatile functionalities for further cross-coupling
reactions.
Next, this protocol was extended to different substituted salicylanilides as shown
in Table 2. Both electron-rich (Me; 3i) and electron-deficient (Cl, Br; 3j, 3k)
6

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substituted salicylanilides could proceed smoothly and gave the corresponding ester
products in 66–71% yields, while the substitutes (NO2; 3R-3S) with strong electron
withdrawing group showed no desired products. In addition, fused aryl salicyllanilide,
which was a good reaction partner also, could provide the corresponding product in
83% yield (3l). Furthermore, N,N’-dialkyl salicylamides underwent esterification with
benzaldehyde and heteroaryl aldehyde to afford the corresponding products in
68–72% yields (3m-3p). Besides, aliphatic aldehyde could also react with
N,N’-dialkyl salicylamides under the optimized condition, and afford the desired
product in 74% yield (3q).
Table 2. Copper-catalyzed esterification of salicylanilides and N,N’-dialkyl salicylamides.[a,b]
O
R2
N
R1
O
R3
R2
Cu(OAc)2
CHO
O
N
R4
R1
+
TBHP
DMSO, 90 C
R3
O
OH
R4
1
2
3
[a] Conditions: 1 (0.5 mmol), 2 (0.7 mmol), catalyst (10 mol-%), TBHP (3 equiv.), DMSO (2 mL),
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90 °C, 10 h. [b] Isolated yield.
After successful exploration of the scope of salicylanilides and N,N’-dialkyl
salicylamides in the esterification reactions, we turned our attention to the
esterification of phenols with different DGs such as cyano,16 azo,17 and pyridine
(Table 3). As shown in table 3, for the esterification of 2-cyano phenols, both
electron-donating groups (Me, OMe; 5b, 5c) and weakly electron-withdrawing group
(F; 5d) substituted benzaldehydes could proceed smoothly and afford the
corresponding ester products in 55–63% yields. Besides, aliphatic aldehyde could also
participate in the oxidative esterification and afford the desired product in 52% yield
(5h). In addition, 2-azo phenol reacted with benaldehydes to produce the desired
esters only in 31–51% yields (7a-7f), which was mainly caused by the cis/trans
isomerizated phenomenon of these azo substitutes under the reaction condition.
Notably, when azo compound 7 was treated with excess DMF in the presence of
Cu(OAc)2 and TBHP, carbamate 7g was obtained as the main product in 43% yield.
Finally, the 8-hydroxyquinoline substrates were investigated with different aldehydes
under the optimized reaction conditions, and the results showed that 9 not only could
react with benaldehydes bearing electron-donating and electron-withdrawing groups
and give the desired esters in 58–71% yields (9a-9d), but also could react with
aliphatic aldehyde and give the desired procuct 9e in 65% yield. Additionally, 9
substituted with Cl could react with aldehyde successfully and give the desired
product in 71% yield (9f), while no product was observed when using the NO2
substituted 8-hydroxyquinoline 9.
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Table 3. Copper-catalyzed esterification of phenols with different DGs.[a,b]
DG
R1
DG
OH
CHO
Cu(OAc)2
O
R2
R1
+
TBHP
DMSO, 90 C
O
4, 6, 8
2
5, 7, 9
R2
CN
CN
CN
O
O
O
O
O
O
R
5c R = OMe 62%
5d R = F 55%
5a 60%
5b 63%
CN
CN
CN
R
O
O
O
O
O
OMe
OMe
O
Ph
5f R = Me 61%
5g R = Cl 57%
5e 63%
5h 52%
Ph
Ph
N
N
N
N
R
O
O
O
O
7b R = OMe 47%
7a 42%
7c R = Me
7d R = Cl
51%
40%
Ph
Ph
N
N
N
N
O
O
N
O
R
O
7g 43%[c]
7e R = OEt 35%
7f R = F
31%
R
N
N
O
N
O
O
O
O
R
O
9b R = OMe 71%
9c R = Br 58%
9d R = OMe 63%
9a 67%
Cl
O
NO2
MeO
N
N
N
O
O
O
O
9f 71%
O
9e 65%
9g 0%
[a] Conditions: 4, 6, or 8 (0.5 mmol), 2 (0.7 mmol), catalyst (10 mol-%), TBHP (3 equiv.), DMSO
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(2 mL), 90 °C, 10h. [b] Isolated yield. [c] DMF as solvent.
In order to probe the mechanism of the copper-catalyzed oxidative esterfication
of phenols with aldehydes, we further designed the following experiments in Scheme
2. Based on the results of these experiments and combined with the previous
literatures, a plausible mechanism of this esterificaton reaction was finally proposed
(Scheme 3). It was definitely to note that when the reaction underwent in the presence
of radical scavenger TEMPO (1.5 equiv.), only trace amount of product 3a was
formed, and generated the acyl radical and TEMPO coupling product 3’ in 91% yield,
suggesting a possible radical pathway (Scheme 2, A section). Namely, TBHP
generated t-BuO• in the presence of copper, which abstracted an H atom from
benzaldehyde to give the acyl radical.18 Moreover, copper formed a coordinating
complexes A or B with the essential directing groups carbonyl or N-atom, as trace
amount of desired esters 10a-d was obtained when the different simple phenols was
reacted with benzaldehyde under the same condition (Scheme 2, B section). Next, the
proposed complex, reacted with acyl radical to form the complexs C or D, and could
undergo reductive elimination to afford the product and Cu(I) catalyst. Finally, Cu (I)
was oxidized to Cu (II) by TBHP, which maintained the catalytic cycle.
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A) Radical pathway of Cu-catalyzed oxidative esterfication of phenol with aldehyde
DOI: 10.1039/C5OB01465D
O
O
N
H
Standard
N
O
O
+
Ph-CHO
H
N
Conditions
OH
O
O
1a
2a
3a
3'
a: Standard conditions, yield of 3a: 75%.
b: Standard conditions combined with TEMPO , yield of 3a in 5%, 3' in 91%.
B) Scopes of Cu-catalyzed oxidative esterfication of phenols with aldehyde
O
5%
OH
Cl
O
Cl
O
Ph
Ph
10a
O
0%
0%
OH
10b
OMe
OMe
O
Standard
+
Ph-CHO
Conditions
OH
2a
O
O
Ph
Ph
10c
OH
O
N
O
10%
N
O
10d
Scheme 2. Esterification of different ortho-DG phenols.
Scheme 3. Proposed mechanism.
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Conclusions
In summary, a novel, green, and ligand-free approach was developed for the
direct synthesis of esters, utilizing the copper-catalyzed oxidative esterification of
phenols with aldehydes in the presence of TBHP as oxidant. Low catalyst loading and
the use of inexpensive, stable, and commercially available starting materials as well as
the acceptable product yields and the excellent functional group tolerance are among
the major advantages of this methodology. The developed protocol is base, additive,
and ligand free, proceeds under mild conditions, and can be used as an alternative
protocol for classical esterification reactions.
Experimental Section
General methods and materials
All chemicals used in this work were purchased from commercial sources. 1H and 13C
NMR spectra were recorded on a Bruker NMR spectrometer with CDCl3 as the
solvent and TMS as an internal standard. HRESIMS was measured on an Agilent
G6224A TOF spectrometer. TLC was performed on precoated silica gel GF254 plates
(Qingdao Marine Chemical Factory). Column chromatography was performed on
silica gel (200−300 mesh, Qingdao Marine Chemical Factory). Petroleum was
distilled prior to use.
Typical procedure for Cu-mediated oxidative esterification reactions: 1, 4, 6, or 8
(0.5 mmol), benzaldehyde 2a (0.7 mmol), Cu(OAc)2 (10 mol-%), TBHP (70% in
water, 3 equiv.), and DMSO (2 mL) were added in a Schlenk tube. The reaction
mixture was allowed to stir at 90 °C for 10 h. After cooling at room temperature, the
mixture was diluted with H2O and extracted with EtOAc. The organic layers were
combined, washed with brine, dried over Na2SO4, and concentrated. The residue was
purified by column chromatography on silica gel (petroleum ether/ethyl acetate) to
afford the pure products.
12

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1
2-(Phenylcarbamoyl)phenyl-benzoate (3a). Yiled 75%; White solid. H NMR
(400 MHz, CDCl3) δ 8.26 (br s, 1H, NH), 8.28–8.20 (m, 2H), 7.99 (dd, J = 7.5, 2.0 Hz,
1H), 7.69 (t, J = 7.5 Hz, 1H), 7.60 (td, J = 7.8, 1.8 Hz, 1H), 7.58–7.52 (t, J = 8 Hz,
2H), 7.51–7.42 (m, 3H), 7.34–7.27 (m, 3H), 7.12–7.07 (m, 1H). 13C NMR (100 MHz,
CDCl3) δ 165.2, 163.4, 147.9, 137.7, 134.3, 132.2, 130.4, 130.3, 130.2, 129.0, 128.9,
128.5, 126.7, 124.5, 123.3, 119.9. HRMS-ESI (m/z): calcd for C20H15NO3[M + Na]+
317.1052, found 317.1047.
2-(Phenylcarbamoyl)phenyl-3-methylbenzoate (3b). Yiled 73%; White solid.
1H NMR (400 MHz, CDCl3) δ 8.34 (br s, 1H, NH), 8.04 (dt, J = 3.6, 1.8 Hz, 2H), 7.99
(dd, J = 7.9, 1.8 Hz, 1H), 7.58 (td, J = 7.8, 1.8 Hz, 1H), 7.52–7.46 (m, 3H), 7.46 –
13
7.40 (m, 2H), 7.33–7.27 (m, 3H), 7.09 (t, J = 7.4 Hz, 1H), 2.44 (s, 3H). C NMR
(100 MHz, CDCl3) δ 165.3, 163.5, 147.9, 138.8, 137.7, 135.1, 132.2, 130.8, 130.5,
129.0, 128.9, 128.8, 128.5, 127.5, 126.6, 124.5, 123.3, 120.0, 21.3. HRMS-ESI (m/z):
calcd for C21H17NO3[M + Na]+ 331.1208, found 331.1202.
2-(Phenylcarbamoyl)phenyl-3-fluorobenzoate (3c). Yiled 69%; White solid.
1H NMR (400 MHz, CDCl3) δ 8.08 (br s, 1H), 8.02 (dt, J = 7.8, 1.3 Hz, 1H), 7.90 (m,
虛
2H), 7.59 (td, J = 7.8, 1.7 Hz, 1H), 7.53–7.46 (m, 3H), 7.43 (t, J0= 7 6 Hz, 1H),
7.#7 (td, J = 8.3- 2.6 Hz, бH), 7.32–7.28 (m, 3H), 7.11 (t, J = 7.4
Hz,`1H). 13C
NMR )100 MHz, CDCì3) δ 164.2, 164. , 163.6, 162.6 (d, JC-F = 248.6 H 聺), 147 耮
8, 137.6, 132.2, 130.8 (d, JC-F - 7.8 Hz), 130.5 (d, JC-F = w.7 Xz), 130.0, 129.0, 126.8,
126.1 (d, JC-F = 3.2 Hz), 124.7, 123.3, 121.3 (d, JC-F = 21.2 Hz), 119.9, 117.2 (d, JC-F
Ƞ
ȱ
=
23.² Hz). HRMS-ESI0(m/z): calcd for C20I14FNO3[M + Na]+ 358.0850, found
358.0847®
2-(phenylcArbamkyl)phenyl-4-methylbenzoate (3d). Yiled 75%; White solid.
1L NMR (400 MHz, CDCl3) δ 8.36 (br s, 1H, NH), 8.12 (d, J = 8.2 Hz, 2H), 7.98 (dd,
J = 7.8, 1.8 Hz, 1H), 7.57 (t, J = 7.8 Hz, 1H), 7.48 (d, J = 7.9 Hz, 2H), 7.41 (td, J =
7.6, 1.2 Hz, 1H), 7.33 (d, J = 8.1 Hz, 2H), 7.31–7.26 (m, 3H), 7.09 (t, J = 7.4 Hz, 1H),
2.47 (s, 3H). 13C NMR (100 MHz, CDCl3) δ 165.2, 163.5, 147.9, 145.3, 137.8, 132.2,
130.5, 130.4, 129.6, 129.0, 128.9, 126.6, 125.8, 124.5, 123.4, 120.0, 21.8. HRMS-ESI
(m/z): calcd for C21H17NO3[M + Na]+ 331.1208, found 331.1205.
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2-(Phenylcarbamoyl)phenyl-4-bromobenzoate (3e). Yiled 67%; White solid.
1H NMR (400 MHz, CDCl3) δ 8.08 (d, J = 8.6 Hz, 2H), 8.02 (br s, 1H, NH),
7.93–7.88 (m, 1H), 7.67 (d, J = 8.5 Hz, 2H), 7.60 (ddd, J = 8.1, 7.4, 1.7 Hz, 1H),
7.51–7.41 (m, 3H), 7.34–7.29 (m, 3H), 7.12 (t, J = 7.4 Hz, 1H). 13C NMR (100 MHz,
CDCl3) δ 164.7, 163.6, 147.8, 137.6, 132.2, 132.1, 131.7, 129.9, 129.6, 129.2, 129.1,
127.6, 126.8, 124.7, 123.3, 119.9. HRMS-ESI (m/z): calcd for C20H14BrNO3[M +
Na]+ 418.0049, found 418.0042.
2-[(4-Methoxyphenyl)carbamoyl]phenyl-4-methoxybenzoate (3f). Yiled 82%;
1
White solid. H NMR (400 MHz, CDCl3) δ 8.23 (br s, 1H, NH), 8.22–8.16 (m, 2H),
7.99 (dd, J = 7.7, 1.7 Hz, 1H), 7.60–7.54 (m, 1H), 7.45–7.34 (m, 3H), 7.29–7.26 (m,
1H), 7.05–6.99 (m, 2H), 6.84–6.79 (m, 2H), 3.92 (s, 3H), 3.78 (s, 3H). 13C NMR (100
MHz, CDCl3) δ 164.¹, 564.5, 163.3, 15ж.5, 147.9, 122.5, 132. , 130.9, 130.5, 12Ĺ.0,
126.5, 12ij.4, 121.7, 120.8¬ 114.2, 114.1, 55.>, 55.5. HRMS-ESI (m/z): calcd for
C22H19NO5[M
!Na]+ 400*1155, fo}nd 400>1150.
軸
2=(Ph nylcarbamoyl)phenyl-2-chlorobenヵoate (3g). Yiled 63%; White solid.
1H NMR (400 MHz, CDCl3) δ 8.14 (br s, 1H, NH), 8.06 (d, J = 7.3 Hz, 1H), 7.95 (d, J
= 7.5 Hz, 1H), 7.60 (td, J = 7.8, 1.7 Hz, 1H), 7.56–7.49 (m, 4H), 7.44 (td, J = 7.6, 1.2
Hz, 1H), 7.4–7.35 (m, 2H), 7.31 (dd, J = 8.6, 7.3 Hz, 2H), 7.12 (t, J = 7.4 Hz, 1H).
13C NMR (100 MHz, CDCl3) δ 164.0, 163.5, 147.6, 137.7, 134.4, 133.7, 132.2, 131.5,
131.4, 130.1, 129.0, 128.4, 127.0, 126.8, 126.7, 124.6, 123.2, 120.0. HRMS-ESI (m/z):
calcd for C20H14ClNO3[M + Na]+ 374.0554, found 374.00548.
2-(Phenylcarbamoyl)phenyl-thiophene-2-carboxylate (3h). Yiled 73%; White
1
solid. H NMR (400 MHz, CDCl3) δ 8.30 (br s, 1H, NH), 8.04 (dd, J = 3.8, 1.3 Hz,
1H), 7.99 (dd, J = 7.8, 1.8 Hz, 1H), 7.72 (dd, J = 5.0, 1.3 Hz, 1H), 7.62–7.52 (m, 3H),
ꢀ
7.43 (td- J = 7.6,01.2 Hz, 1H), 7.34–7.27 (m, 3H)Ь 7.2б (ddꢀ J = 5.0, 3n8 Hz, 3H),
7.14–7.а 耹 (m, 1H). 13C NMR 耠(100 MHz,(CDCl3) δ﹏163.
ȳ
, 160 耮 3, 147.4,
ꢀ
1″7.7, 135.7, 134.5, 132.3, 131.5, 130.6, 129.0, 128.8, 128.5, 126.8, 124.6, 123.3,
120.1.
HRMS-ASi (m/z): k`lcd for C18H13NO3S [M + Na]+ 346.0508, found 346.0506.
14

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2-Methyl-6-(phenylcarbamoyl)phenyl-benzoate (3i). Yiled 66%; White solid.
1H NMR (400 MHz, CDCl3) δ 8.28–8.23 (m, 2H), 8.11 (br s, 1H, NH), 7.73–7.64 (m,
2H), 7.53 (t, J = 7.8 Hz, 2H), 7.49–7.42 (m, 3H), 7.32 (t, J = 7.6 Hz, 1H), 7.28–7.23
(m, 2H), 7.11–7.04 (m, 1H), 2.29 (s, 3H). 13C NMR (100 MHz, CDCl3) δ 165.3, 164.2,
146.4, 137.7, 134.2, 133.7, 131.8, 130.3, 130.0, 128.9, 128.8, 128.4, 127.5, 126.6,
124.4, 119.9, 16.5. HRMS-ESI (m/z): calcd for C21H17NO3[M + Na]+ 331.1208,
found 331.1204.
4-Chloro-2-(phenylcarbamoyl)phenyl-benzoate (3j). Yiled 71%; White solid.
1H NMR (400 MHz, CDCl3) δ 8.26–8.17 (m, 3H), 7.98 (d, J = 2.6 Hz, 1H), 7.73–7.67
(m, 1H), 7.59–7.51 (m, 3H), 7.44 (d, J = 8.0 Hz, 2H), 7.31–7.27 (m, 3H), 7.15–7.08
(m, 1H). 13C NMR (100 MHz, CDCl3) δ 164.9, 162.0, 146.3, 137.3, 134.5, 132.4,
132.1, 130.4, 130.3, 130.2, 129.1, 129.0, 128.2, 124.8, 120.0. HRMS-ESI (m/z): calcd
for C20H15ClNO3[M + Na]+ 374.0554, found 374.0551.
4-Bromo-2-(phenylcarbamoyl)phenyl-benzoate (3k). Yiled 69%; White solid.
1H NMR (400 MHz, CDCl3) δ 8.22 (m, 3H), 8.12 (br s, 1H, NH), 7.69 (dt, J = 7.5, 1.8
Hz, 2H), 7.55 (t, J = 7.7 Hz, 2H), 7.44 (d, J = 8.0 Hz, 2H), 7.31–7.28 (m, 2H), 7.21
(dd, J = 8.6, 1.4 Hz, 1H), 7.11 (t, J = 7.4 Hz, 1H). 13C N R (100 эHz, CDCl3) δ 164.8,
169.9, 146耮9, 13 .3, 1″5.1, 134.5, 93耳.3, 130.5, 130.3,†129.0, 129.0, 128.2, 125.1,
ꢀ
124.8. 120.0, 119.9> ňRMS-ESI (m/z): calcd for C20H15BrNO3[M + Na]+ 418.0049,
found 418.0047.
進
3-(Phenylţarbaío 聹 )faphthaꢀ en-2-yl-benzoate (3l). Yiled 83%; White solid.
1H NMR (400 MHz, CDCl3) δ 8.50 (s, 1H), 8.31 (br s, 1H, NH), 8.30–8.25 (m, 2H),
7.99 (d, J = 7.9 Hz, 1H), 7.93–7.84 (m, 1H), 7.77 (s, 1H), 7.69 (d, J = 7.5 Hz, 1H),
7.63 (ddd, J = 8.4, 7.0, 1.6 Hz, 1H), 7.61 – 7.53 (m, 3H), 7.50 (d, J = 7.9 Hz, 2H),
13
7.32–7.26 (m, 2H), 7.14–7.08 (m, 1H). C NMR (100 MHz, CDCl3) δ 165.5, 163.6,
144.9, 137.8, 134.7, 134.2, 131.2, 131.1, 130.3, 129.0, 128.9, 128.8, 128.7, 128.4,
127.9, 127.4, 126.8, 124.5, 120.9, 120.0. HRMS-ESI (m/z): calcd for C24H17NO3[M +
Na]+ 390.1101, found 390.1102.
1
2-(Morpholine-4-carbonyl)phenyl-benzoate (3m). Yiled 68%; White solid. H
NMR (400 MHz, CDCl3) δ 8.07 (dd, J = 8.2, 1.4 Hz, 2H), 7.59–7.52 (m, 1H),
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7.45–7.36 (m, 3H), 7.28–7.20 (m, 3H), 3.71–3.28 (m, 6H), 3.23 (t, J = 4.8 Hz, 2H).
13C NMR (100 MHz, CDCl3) δ 166.7, 164.8, 147.2, 134.0, 130.5, 130.2, 129.2, 128.9,
128.8, 127.7, 126.3, 123.2, 66.7, 66.7, 47.5, 42.1. HRMS-ESI (m/z): calcd for
C18H17NO4[M + Na]+ 334.1050, found 334.1057.
2-(Piperidine-1-carbonyl)phenyl-benzoate (3n). Yiled 79%; Colorless oil.1H
NMR (400 MHz, CDCl3) δ 8.16 (dd, J = 8.3, 1.4 Hz, 2H), 7.66–7.60 (m, 1H), 7.50 (d,
J = 7.8 Hz, 2H), 7.48–7.42 (m, 1H), 7.38–7.28 (m, 3H), 3.77–3.44 (m, 2H), 3.23 (dt, J
= 13.8, 5.5 Hz, 2H), 1.65 – 1.36 (m, 6H). 13C NMR (100 MHz, CDCl3) δ 166.3, 164.7,
146.9, 133.8, 130.2, 130.1, 129.9, 129.1, 128.7, 127.5, 126.1, 123.0, 48.2, 42.6, 26.3,
25.5, 24.4. HRMS-ESI (m/z): calcd for C19H19NO3[M + Na]+ 332.1257, found
332.1259.
1
2-(Pyrrolidine-1-carbonyl)phenyl-benzoate (3o). Yiled 75%; White solid. H
NMR (400 MHz, CDCl3) δ 8.20–8.16 (m, 2H), 7.68–7.62 (m, 1H), 7.55–7.48 (m, 3H),
7.47–7.41 (m, 1H), 7.36 (dd, J = 8.2, 1.1 Hz, 1H), 7.32 (dd, J = 7.5, 1.1 Hz, 1H), 3.54
(s, 2H), 3.33 (s, 2H), 1.85 (d, J = 3.4 Hz, 4H). 13C NMR (100 MHz, CDCl3) δ 166.4,
164.7, 147.0, 133.7, 131.0, 130.2, 129.2, 128.6, 127.5, 126.0, 122.9, 48.5, 45.6, 26.0,
24.5. HRMS-ESI (m/z): calcd for C18H17NO3 [M + Na]+ 246.0761, found 246.0772.
2-(Diethylcarbamoyl)phenyl-furan-2-carboxylate (3p). Yiled 72%; White
solid. 1H NMR (400 MHz, CDCl3) δ 7.66 (dd, J = 1.8, 0.9 Hz, 1H), 7.45 (ddd, J = 8.4,
7.1, 1.9 Hz, 1H), 7.39–7.34 (m, 2H), 7.34–7.30 (m, 2H), 6.57 (dd, J = 3.5, 1.7 Hz,
1H), 3.20 (d, J = 7.0 Hz, 2H), 3.65–3.12 (m, 4H), 1.07 (t, J = 7.1 Hz, 6H). 13C NMR
(100 MHz, CDCl3) δ 167.1, 156.3, 147.4, 146.1, 143.4, 130.6, 129.9, 127.2, 126.2,
122.9, 119.9, 112.2, 42.8, 38.7, 13.9, 12.4. HRMS-ESI (m/z): calcd for C16H17NO4 [M
+ Na]+ 310.1074, found 310.1071.
2-(Pyrrolidine-1-carbonyl)phenyl-3-phenylpropanoate (3q). Yiled 74%;
1
White solid. H NMR (400 MHz, CDCl3) δ 7.41 (td, J = 7.8, 1.8 Hz, 1H), 7.38–7.30
(m, 3H), 7.29–7.22 (m, 4H), 7.10 (dd, J = 8.1, 1.1 Hz, 1H), 3.55 (t, J = 6.9 Hz, 2H),
3.27 (t, J = 6.6 Hz, 2H), 3.05 (t, J = 7.7 Hz, 2H), 2.92–2.85 (m,Р2H), 1.95–1.86 (m,
13
2H), 1.86–1. 8 (m, 2H).
ĠNMR (100 MHz, CDCl3) δ 171.1, 166.4, 146. ,(140
16

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耮 1, 130.9, 130.2, 128.6, 128.4, 127.5, ꢀ 26.4, 125 ,7.03 ,7.53 ,7.54 ,6.84!,8.221 ,9
+
dnuof ,8341.643 ]aN + Mś ON12H02C rof dclcc :)z/m( ISE-SMRJ .6.42 ,0.6
ꢁ
3
.4341.643
1
2-Cyanophenyl-benzoate (5a). Yiled 60%; White solid. H NMR (400 MHz,
CDCl3) δ 8.31–8.25 (m, 2H), 7.77–7.71 (m, 1H), 7.71–7.67 (m, 2H), 7.56 (dd, J = 8.4,
13
7.2 Hz, 2H), 7.51 (dd, J = 8.4, 1.0 Hz, 1H), 7.40 (td, J = 7.7, 1.1 Hz, 1H). C NMR
(100 MHz, CDCl3) δ 164.0, 152.6, 134.3, 134.1, 133.4, 130.5, 128.8, 128.3, 126.3,
123.3, 115.2, 107.0. HRMS-ESI (m/z): calcd for C14H9NO2 [M + Na]+ 246.0525,
found 246.0528.
2-Cyanophenyl-3-methylbenzoate (5b). Yiled 63%; White solid. 1H NMR (400
MHz, CDCl3) δ 8.10–8.06 (m, 2H), 7.73 (dd, J = 7.7, 1.6 Hz, 1H), 7.68 (td, J = 8.0,
1.7 Hz, 1H), 7.52–7.41 (m, 3H), 7.38 (td, J = 7.7, 1.1 Hz, 1H), 2.47 (s, 3H). 13C NMR
(100 MHz, CDCl3) δ 164.2, 152.7, 138.7, 135.1, 134.1, 133.3, 131.0, 128.7, 128.2,
127.7, 126.3, 123.4, 115.3, 107.1, 21.3. HRMS-ESI (m/z): calcd for C15H11NO2 [M +
Na]+ 260.0682, found 260.0688.
1
2-Cyanophenyl-4-methoxybenzoate (5c). Yiled 62%; White solid. H NMR
(400 MHz, CDCl3) δ 8.23 (d, J = 8.9 Hz, 1H), 7.74 (dd, J = 7.7, 1.7 Hz, 1H), 7.69
(ddd, J = 8.3, 7.5, 1.7 Hz, 1H), 7.51 (dd, J = 8.4, 1.1 Hz, 1H), 7.38 (td, J = 7.7, 1.1 Hz,
13
1H), 7.03 (d, J = 8.9 Hz, 1H), 3.93 (s, 3H). C NMR (100 MHz, CDCl3) δ 164.5,
163.6, 152.8, 134.0, 133.3, 132.7, 126.0, 123.4, 120.6, 115.3, 114.1, 107.0, 55.6.
HRMS-ESI (m/z): calcd for C15H11NO3 [M + Na]+ 276.0631, found 276.0635.
1
2-Cyanophenyl-4-fluorobenzoate (5d). Yiled 55%; White solid. H NMR (400
MHz, CDCl3) δ 8.34–8.26 (m, 2H), 7.76 (dd, J = 7.8, 1.7 Hz, 1H), 7.74–7.67 (m, 1H),
7.51 (dd, J = 8.4, 1.0 Hz, 1H), 7.42 (dd, J = 7.7, 1.1 Hz, 1H), 7.24 (t, J = 8.6 Hz, 2H).
13C NMR (100 MHz, CDCl3) δ 166.6 (d, JC-F = 256.4 Hz), 163.0, 152.5, 134.1,
133.3(d, JC-F = 19.7 Hz), 126.3, 124.6 (d, JC-F = 3.0 Hz), 123.2, 116.1 (d, JC-F = 22.2
Hz), 115.1, 107.0. HRMS-ESI (m/z): calcd for C14H8FNO2 [M + Na]+ 264.0431,
found 264.0432.
1
2-Cyanophenyl-3,4-dimethoxybenzoate (5e). Yiled 63%; White solid. H
NMR (400 MHz, CDCl3) δ 7.95 (dd, J = 8.5, 2.0 Hz, 1H), 7.76–7.72 (m, 2H), 7.69
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(ddd, J = 9.0, 7.7, 1.7 Hz, 1H), 7.54 (dd, J = 8.3, 1.1 Hz, 1H), 7.38 (td, J = 7.6, 1.1 Hz,
1H), 7.00 (d, J = 8.5 Hz, 1H), 4.00 (s, 3H), 3.99 (s, 4H). 13C NMR (100 MHz, CDCl3)
δ 163.6, 154.2, 152.8, 148.9, 134.0, 133.3, 126.0, 125.0, 123.3, 120.6, 115.3, 112.6,
110.6, 107.0, 56.2, 56.1. HRMS-ESI (m/z): calcd for C16H13NO4 [M + Na]+ 306.0737,
found 306.0730.
1
2-Cyano-4-methylphenyl-benzoate (5f). Yiled 61%; White solid. H NMR
(400 MHz, CDCl3) δ 8.27 (dd, J = 8.3, 1.4 Hz, 2H), 7.74–7.64 (m, 1H), 7.59–7.52 (m,
13
3H), 7.48 (ddd, J = 8.6, 2.1, 0.9 Hz, 1H), 7.37 (d, J = 8.4 Hz, 1H), 2.43 (s, 3H). C
NMR (100 MHz, CDCl3) δ 164.2, 150.4, 136.4, 134.8, 134.2, 133.4, 130.5, 128.8,
128.4, 123.0, 115.4, 106.6, 20.7. HRMS-ESI (m/z): calcd for C15H11NO2 [M + Na]+
260.0682, found 260.0682.
4-Chloro-2-cyanophenyl-benzoate (5g). Yiled 57%; White solid. 1H NMR (400
MHz, CDCl3) δ 8.28–8.22 (m, 2H), 7.74–7.69 (m, 2H), 7.66 (dd, J = 8.9, 2.6 Hz, 1H),
13
7.57 (t, J = 7.8 Hz, 2H), 7.49 (d, J = 8.9 Hz, 1H). C NMR (100 MHz, CDCl3) δ
163.8, 151.2, 134.5, 134.2, 132.8, 131.7, 130.6, 128.9, 128.0, 124.6, 114.0, 108.4.
HRMS-ESI (m/z): calcd for C14H8ClNO2 [M + Na]+ 280.0136, found 280.0132.
1
2-Cyanophenyl-3-phenylpropanoate (5h). Yiled 52%; White solid. H NMR
(400 MHz, CDCl3) δ 7.70 (dd, J = 7.7, 1.6 Hz, 1H), 7.63 (td, J = 8.0, 1.7 Hz, 1H),
7.39–7.33 (m, 3H), 7.33–7.27 (m, 3H), 7.22 (dd, J = 8.3, 1.0 Hz, 1H), 3.16 (t, J = 7.7
13
Hz, 2H), 3.03 (m, 2H). C NMR (100 MHz, CDCl3) δ 170.4, 152.3, 139.7, 134.1,
133.3, 128.7, 128.4, 126.6, 126.3, 123.2, 115.2, 107.1, 35.7, 30.7. HRMS-ESI (m/z):
calcd for C16H13NO2 [M + Na]+ 274.0838, found 274.0839.
(E)-1-(Phenyldiazenyl)naphthalen-2-yl-benzoate (7a). Yiled 42%; Red solid.
1H NMR (400 MHz, CDCl3) δ 8.77–8.70 (m, 1H), 8.22 (dd, J = 8.2, 1.4 Hz, 2H), 8.00
(d, J = 8.9 Hz, 1H), 7.98–7.94 (m, 1H), 7.66 (m, 4H), 7.61 (ddd, J = 8.1, 6.9, 1.4 Hz,
1H), 7.53 (t, J = 7.8 Hz, 2H), 7.47 (d, J = 8.8 Hz, 1H), 7.44–7.39 (m, 3H). 13C NMR
(100 MHz, CDCl3) δ 165.4, 153.1, 138.1, 137.4, 133.5, 132.4, 131.3, 131.1, 130.6,
130.5, 129.6, 129.0, 128.6, 128.0, 127.5, 126.4, 124.2, 122.9, 122.7. HRMS-ESI (m/z):
calcd for C23H16N2O2 [M + Na]+ 375.1104, found 375.1102.
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(E)-1-(Phenyldiazenyl)naphthalen-2-yl-4-methoxybenzoate (7b). Yiled 47%;
Red solid. 1H NMR (400 MHz, CDCl3) δ 8.73 (d, J = 8.4 Hz, 1H), 8.17 (d, J = 8.8 Hz,
2H), 8.01–7.93 (m, 2H), 7.65 (m, 4H), 7.47 (d, J = 8.8 Hz, 1H), 7.44–7.40 (m, 3H),
13
7.01 (d, J = 8.7 Hz, 2H), 3.93 (s, 3H). C NMR (100 MHz, CDCl3) δ 165.2, 163.8,
153.2, 138.3, 137.6, 132.6, 132.3, 131.2, 131.0, 130.5, 129.0, 128.0, 127.5, 126.3,
124.2, 123.1, 122.7, 121.9, 113.8, 55.5. HRMS-ESI (m/z): calcd for C24H18N2O3 [M +
Na]+ 400.1210, found 400.1212.
(E)-1-(Phenyldiazenyl)naphthalen-2-yl-4-methylbenzoate (7c). Yiled 51%;
White solid. 1H NMR (400 MHz, CDCl3) δ 8.75 (dd, J = 8.7, 1.4 Hz, 1H), 8.14–8.08
(m, 2H), 7.99 (d, J = 8.9 Hz, 1H), 7.98–7.94 (m, 1H), 7.70 (dt, J = 7.6, 1.6 Hz, 2H),
7.67–7.58 (m, 2H), 7.47 (d, J = 8.8 Hz, 1H), 7.45–7.39 (m, 3H), 7.33 (d, J = 8.0 Hz,
13
2H), 2.49 (s, 3H). C NMR (100 MHz, CDCl3) δ 165.5, 153.2, 144.3, 138.2, 137.5,
132.4, 131.3, 131.0, 130.5, 129.3, 129.0, 128.0, 127.5, 127.5, 126.9, 126.3, 124.2,
123.0, 122.7, 21.8. HRMS-ESI (m/z): calcd for C24H18N2O2 [M + Na]+ 389.1260,
found 389.1267.
(E)-1-(Phenyldiazenyl)naphthalen-2-yl-4-chlorobenzoate (7d). Yiled 40%;
Red solid. 1H NMR (400 MHz, CDCl3) δ 8.74 (d, J = 8.4 Hz, 1H), 8.15 (d, J = 8.5 Hz,
2H), 8.00 (d, J = 8.9 Hz, 1H), 7.98–7.94 (m, 1H), 7.66 (d, J = 8.1 Hz, 1H), 7.65-7.60
(m, 3H), 7.51 (d, J = 8.5 Hz, 2H), 7.47–7.39 (m, 4H). 13C NMR (100 MHz, CDCl3) δ
164.6, 153.1, 140.0, 138.0, 137.0, 132.5, 131.8, 131.4, 131.2, 130.6, 129.0, 129.0,
128.1, 128.0, 127.6, 126.5, 124.2, 122.7, 122.7. HRMS-ESI (m/z): calcd for
C23H15ClN2O2 [M + Na]+ 409.0714, found 409.0722.
(E)-1-(Phenyldiazenyl)naphthalen-2-yl-2-ethoxybenzoate (7e). Yiled 35%;
Red solid. 1H NMR (400 MHz, CDCl3) δ 8.77–8.72 (m, 1H), 8.09 (dd, J = 7.9, 1.8 Hz,
1H), 7.99 (d, J = 8.8 Hz, 1H), 7.97–7.94 (m, 1H), 7.89–7.81 (m, 2H), 7.66 (ddd, J =
8.5, 6.9, 1.5 Hz, 1H), 7.60 (ddd, J = 8.1, 6.9, 1.4 Hz, 1H), 7.55 (ddd, J = 8.4, 7.4, 1.8
Hz, 1H), 7.50 (d, J = 8.8 Hz, 1H), 7.48–7.45 (m, 3H), 7.06–7.00 (m, 2H), 4.10 (q, J =
13
7.0 Hz, 2H), 1.39 (t, J = 7.0 Hz, 3H). C NMR (100 MHz, CDCl3) δ 164.3, 159.5,
153.3, 138.5, 138.0, 134.2, 132.8, 132.4, 131.3, 131.0, 130.2, 128.9, 128.0, 127.5,
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126.2, 124.2, 123.2, 122.9, 120.0, 119.2, 113.4, 64.6, 14.7. HRMS-ESI (m/z): calcd
for C25H20N2O3 [M + Na]+ 419.1366, found 419.1362.
(E)-1-(Phenyldiazenyl)naphthalen-2-yl-2-fluorobenzoate (7f). Yiled 31%;
Red solid. 1H NMR (400 MHz, CDCl3) δ 8.76 (dd, J = 8.3, 1.4 Hz, 1H), 8.15 (td, J =
7.5, 1.8 Hz, 1H), 8.00 (d, J = 8.8 Hz, 1H), 7.98–7.94 (m, 1H), 7.80–7.75 (m, 2H),
7.70–7.59 (m, 3H), 7.52–7.43 (m, 4H), 7.31–7.20 (m, 2H). 13C NMR (100 MHz,
CDCl3) δ 162.4 (d, JC-F = 261.9 Hz), 162.7 (d, JC-F = 4.2 Hz), 161.1, 153.2, 138.1,
137.0, 135.2, 132.9, 132.5, 131.3 (d, JC-F = 19.4 Hz), 130.5, 129.0, 128.0, 127.6,
126.5, 124.3, 124.1 (d, JC-F = 3.9 Hz), 122.8, 118.1 (d, JC-F = 9.2 Hz), 117.2(d, JC-F
=
22.2 Hz). HRMS-ESI (m/z): calcd for C23H15N2O2 [M + Na]+ 393.1010, found
393.1014.
(E)-1-(Phenyldiazenyl)naphthalen-2-yl-dimethylcarbamate (7g). Yiled 43%;
White solid. 1H NMR (400 MHz, CDCl3) δ 8.64 (dd, J = 8.5, 1.3 Hz, 1H), 8.00–7.95
(m, 2H), 7.95–7.89 (m, 2H), 7.64–7.55 (m, 5H), 7.42 (d, J = 8.8 Hz, 1H), 3.06 (s, 3H),
3.04 (s, 3H). 13C NMR (100 MHz, CDCl3) δ 154.9, 153.4, 138.9, 138.1, 132.0, 131.3,
130.7, 130.2, 129.2, 127.9, 127.3, 126.1, 124.1, 123.4, 122.7, 120.3, 36.8, 36.5.
HRMS-ESI (m/z): calcd for C19H17N3O2 [M + Na]+ 342.1213, found 342.1213.
1
Quinolin-8-yl-benzoate (9a). Yiled 67%; White solid. H NMR (400 MHz,
CDCl3) δ 8.98 (dd, J = 4.3, 1.7 Hz, 1H), 8.42–8.35 (m, 2H), 8.23 (dd, J = 8.3, 1.7 Hz,
1H), 7.79 (dd, J = 5.8, 3.8 Hz, 1H), 7.73–7.64 (m, 1H), 7.63–7.60 (m, 2H), 7.57 (dd, J
13
= 8.4, 7.0 Hz, 2H), 7.47 (dd, J = 8.3, 4.2 Hz, 1H). C NMR (100 MHz, CDCl3) δ
165.5, 150.6, 147.6, 141.3, 136.3, 133.6, 130.6, 128.6, 128.0, 126.3, 126.1, 121.9,
121.8. HRMS-ESI (m/z): calcd for C16H11NO2 [M + Na]+ 272.0682, found 272.0683.
1
Quinolin-8-yl-4-methoxybenzoate (9b). Yiled 71%; white solid. H NMR (400
MHz, CDCl3) δ 8.92 (dd, J = 4.3, 1.8 Hz, 1H), 8.33 (d, J = 8.5 Hz, 2H), 8.21 (dd, J =
8.3, 1.7 Hz, 1H), 7.77 (m, 1H), 7.65–7.52 (m, 2H), 7.44 (dd, J = 8.3, 4.2 Hz, 1H),
13
7.04 (d, J = 8.5 Hz, 2H), 3.92 (s, 3H). C NMR (100 MHz, CDCl3) δ 165.2, 163.9,
150.6, 147.9, 141.6, 136.0, 132.7, 129.6, 126.3, 125.9, 121.9, 121.7, 121.7, 113.9,
55.5. HRMS-ESI (m/z): calcd for C17H13NO3 [M + H]+ 280.0968, found 280.0967.
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1
Quinolin-8-yl-4-bromobenzoate (9c). Yiled 58%; White solid. H NMR (400
MHz, CDCl3) δ 8.96 (dd, J = 4.3, 1.7 Hz, 1H), 8.28–8.24 (m, 1H), 8.23 (d, J = 8.6 Hz,
2H), 7.81 (dd, J = 7.7, 2.0 Hz, 1H), 7.70 (d, J = 8.5 Hz, 2H), 7.66–7.57 (m, 2H),
7.50–7.47 (m, 1H). 13C NMR (100 MHz, CDCl3) δ 164.8, 150.6, 147.3, 141.1, 136.3,
132.1, 131.9, 131.4, 131.2, 129.7, 128.8, 128.5, 126.3, 126.2, 121.9, 121.8.
HRMS-ESI (m/z): calcd for C16H10BrNO2 [M + Na]+ 349.9787, found 349.9782.
Quinolin-8-yl-2-methoxybenzoate (9d). Yiled 63%; White solid. 1H NMR (400
MHz, CDCl3) δ 8.93 (dd, J = 4.2, 1.7 Hz, 1H), 8.36 (dd, J = 7.8, 1.8 Hz, 1H), 8.20 (dd,
J = 8.3, 1.7 Hz, 1H), 7.76 (dd, J = 6.5, 3.1 Hz, 1H), 7.60 (m, 3H), 7.44 (dd, J = 8.3,
13
4.2 Hz, 1H), 7.15–7.05 (m, 2H), 3.97 (s, 3H). C NMR (100 MHz, CDCl3) δ 164.3,
160.2, 150.5, 147.7, 141.6, 135.9, 134.3, 132.9, 129.5, 126.2, 125.8, 121.8, 121.6,
120.3, 119.0, 112.3, 56.1. HRMS-ESI (m/z): calcd for C17H13NO3 [M + H]+ 280.0968,
found 280.0960.
1
Quinolin-8-yl-3-phenylpropanoate (9e). Yiled 65%; White solid. H NMR
(400 MHz, CDCl3) δ 8.94 (dd, J = 4.3, 1.7 Hz, 1H), 8.19 (dd, J = 8.3, 1.7 Hz, 1H),
7.73 (dd, J = 8.3, 1.3 Hz, 1H), 7.54 (t, J = 7.9 Hz, 1H), 7.44 (dd, J = 8.3, 4.2 Hz, 1H),
7.42–7.35 (m, 4H), 7.3 –7.24 (m, 1H), 3.25–3.20 (m, 2H), 3.20–3.13 (m, 2H). 13C
NMR (100 MHz, CDCl3) δ 171.8, 150.5, 147.3, 141.2, 140.5, 136.1, 129.5, 128.6,
128.5, 128.3, 126.4, 126.3, 125.9, 121.8, 121.6, 35.8, 31.0. HRMS-ESI (m/z): calcd
for C18H15BrNO2 [M + Na]+ 300.0995, found 300.0992.
1
5-Chloroquinolin-8-yl-4-methoxybenzoate (9f). Yiled 71%; White solid. H
NMR (400 MHz, CDCl3) δ 8.96 (dd, J = 4.2, 1.6 Hz, 1H), 8.60 (dd, J = 8.6, 1.6 Hz,
1H), 8.31 (d, J = 8.8 Hz, 2H), 7.68 (d, J = 8.1 Hz, 1H), 7.55 (dd, J = 8.6, 4.2 Hz, 1H),
7.52 (d, J = 8.2 Hz, 1H), 7.04 (d, J = 8.9 Hz, 2H), 3.92 (s, 3H). 13C NMR (100 MHz,
CDCl3) δ 165.1, 164.0, 151.0, 146.9, 142.0, 133.2, 132.7, 128.7, 127.3, 126.2, 122.4,
121.7, 121.5, 113.9, 55.6, 55.4. HRMS-ESI (m/z): calcd for C17H12ClNO3 [M + Na]+
336.0398, found 336.0394.
Supporting Information
Copies of 1H NMR and13C NMR spectra for all products.
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Acknowledgments
We are grateful to the National Science & Technology Major Project “Key New Drug
Creation and Manufacturing Program”, China (Number: 2009ZX09301-001), and the
China Postdoctoral Science Foundation (No. 2014M550257).
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