Transition-metal- and oxidant-free three-component reaction of quinoline: N -oxides, sodium metabisulfite and aryldiazonium tetrafluoroborates via a dual radical coupling process

Article abstract of DOI:10.1039/c9ob02106j

A convenient and straightforward three-component transformation of quinoline N-oxides, sodium metabisulfite and aryldiazonium tetrafluoroborates has been developed, providing the target products in moderate to good yields. Compared with previous studies, the present methodology avoids the use of transition-metal catalysts and excess oxidants, providing a simple and practical alternative approach for the construction of 2-sulfonylquinolines. Control experiments indicate that a dual radical coupling process is responsible for this reaction.

Full text of DOI:10.1039/c9ob02106j

Organic &
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Transition-metal- and oxidant-free
three-component reaction of quinoline
N-oxides, sodium metabisulfite and
aryldiazonium tetrafluoroborates via
a dual radical coupling process†
Cite this: Org. Biomol. Chem., 2019,
17, 9479
a
Guirong You,a Dan Xi,b Jian Sun,a Liqiang Haoa and Chengcai Xia
*
A convenient and straightforward three-component transformation of quinoline N-oxides, sodium meta-
bisulfite and aryldiazonium tetrafluoroborates has been developed, providing the target products in mod-
erate to good yields. Compared with previous studies, the present methodology avoids the use of tran-
sition-metal catalysts and excess oxidants, providing a simple and practical alternative approach for the
construction of 2-sulfonylquinolines. Control experiments indicate that a dual radical coupling process is
responsible for this reaction.
Received 28th September 2019,
Accepted 17th October 2019
DOI: 10.1039/c9ob02106j
rsc.li/obc
far, a number of transformations have been reported, such as
arylation,6 alkylation,7 alkenylation,8 alkynylation,9 acylation,10
Introduction
The heterocyclic aromatic sulfone skeleton has been recog- etherification,11 esterification,12 trifluoromethylation,13 halo-
nized as an important building block in organic synthesis, genation,14 hydroxylation,15 amination,16 amidation,17 azida-
medicinal chemistry, and advanced materials.1 Traditional tion,18 phosphorization,19 and thioetherification.20 Recently,
methods to prepare such compounds are nucleophilic substi- the development of a two-component reaction for the construc-
tution transformations of aryl halides with thiols, followed by tion of 2-sulfonylquinolines from quinoline N-oxides has also
the oxidation of the corresponding thioethers.2 However, some attracted much attention.21 The main mechanism for such a
aryl halides are not commercially available and are difficult to transformation is nucleophilic addition, which has been well
prepare. In addition, plenty of oxidants should be employed in established.21a–g In sharp contrast, C2–H sulfonylation of qui-
the second step. Such problems violate the purpose of green noline N-oxides through a radical pathway continues to be
chemistry. Therefore, it is necessary to develop simple and scarce.21h–j In 2016, Pan, Han and co-workers reported the first
efficient approaches for the synthesis of heterocyclic aromatic example of copper-catalyzed C2-sulfonylation of quinoline
sulfones from a synthetic practicality standpoint.3
N-oxides with sodium sulfinates through radical coupling
Quinoline and its derivatives have received considerable (Scheme 1a).21i In 2018, He et al. achieved a K2S2O8-mediated
attention, as these compounds exhibit numerous biological C2-sulfonylation of quinoline N-oxides with sodium sulfinates
activities and pharmacological effects.4 In this regard, the via a dual radical coupling process (Scheme 1a).21j Very
development of new approaches for the construction of quino- recently, the same group demonstrated a visible-light-induced
line-containing compounds is highly desired. In recent years, deoxygenative C2-sulfonylation of quinoline N-oxides with sul-
the C–H functionalization of quinoline N-oxides has been finic acids (Scheme 1b).21j Despite these great advancements,
regarded as a powerful tool for direct modification at the C2 such transformations required catalysts and excess oxidants,
and C8 positions of quinoline and its derivatives, since such a which failed to meet the principle of atom economy.
strategy leads to high efficiency and good atom economy.5 So Furthermore, the commonly employed sulfonylating reagents
in previous studies were limited to benzene sulfonyl chloride,
sodium benzenesulfinate, benzenesulfonyl hydrazide, and
benzene sulfinic acid. Therefore, it is still meaningful to
develop novel approaches for C2-sulfonylation of quinoline
N-oxides by using other sulfone sources.
aPharmacy College, Shandong First Medical University & Shandong Academy of
Medical Sciences, Taian 271000, China. E-mail: xiachc@163.com
bShandong Institute for Product Quality Inspection, Jinan 250102, China
†Electronic supplementary information (ESI) available: Detailed experimental
In recent years, great efforts have been devoted to the use of
sulfur dioxide as a sulfone source for the synthesis of hetero-
procedures and analytical data. CCDC 1953274. For ESI and crystallographic
data in CIF or other electronic format see DOI: 10.1039/c9ob02106j
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Table 1 Screening of reaction conditionsa
Na2S2O5
[x equiv.]
Temp.
[°C]
Yieldb
[%]
Entry
Solvent
1
2
3
4
5
6
7
8
CH3CN
DMF
1,4-Dioxane
Toluene
THF
H2O
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.5
2.0
2.5
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
30
30
30
30
30
30
30
30
30
30
50
80
rt
25
18
Trace
Trace
29
Trace
38
49
58
57
71
69
18
53
72
Trace
70
21
9
10
11
12
13
14c
15d
16e
17f
18g
50
50
50
50
50
Scheme 1 Direct C2–H sulfonylation of quinoline N-oxides.
cyclic aromatic sulfones. Generally, DABCO·(SO2)2,22 metabi-
sulfites23 and rongalite24 were commonly used as the source of
sulfur dioxide. More recently, Wang and coworkers reported
the first example of three-component C2-sulfonylation of qui-
nolone N-oxides with DABCO·(SO2)2 and phenyldiazonium tet-
a Reaction conditions: 1a (0.2 mmol), Na2S2O5 (x equiv.), 2a
(2.0 equiv.), solvent (2.0 mL), temp., N2, 12 h. b Isolated yields. c 2a
(1.0 equiv.). d 2a (1.5 equiv.). e Under air. f The reaction was performed
for 24 h. g Used K2S2O5 instead of Na2S2O5.
rafluoroborates through
a reductive elimination process
(Scheme 1c).22v Although this work fills up the research gap,
only 18 examples have been explored. Furthermore, the copper
catalyst is toxic, and removal of trace amounts of copper resi-
dues from the products is quite costly and challenging, while
crucial, especially in the pharmaceutical industry. To avoid the
use of metal catalysts, the development of a transition-metal-
free method is imperative. As part of our investigations
devoted to the synthesis of nitrogen containing heterocyclic
was conducted at different reaction temperatures. It was found
that the reaction was sensitive to the reaction temperature and
a higher yield of 71% was obtained when the reaction was per-
formed at 50 °C (Table 1, entries 11–13). To further improve
the yield of the target product, the amount of phenyl diazo-
nium tetrafluoroborate (2a) was also studied (Table 1, entries
14 and 15). However, no better result was obtained. It was
worth noting that the yield of the target product showed no
obvious change when the amount of phenyl diazonium tetra-
fluoroborate (2a) was reduced from 2.0 equivalents to 1.5
equivalents (Table 1, entry 15). No desired product was
observed when the reaction was carried out under an air atmo-
sphere (Table 1, entry 16). Further investigations on the reac-
tion and sulfone source did not improve the product yield
(Table 1, entries 17 and 18).
compounds,25 herein, we report
a transition-metal- and
oxidant-free C2-sulfonylation of quinoline N-oxides with
sodium metabisulfite and aryldiazonium tetrafluoroborates,
providing a new methodology for the synthesis of 2-sulfonyl-
quinolines (Scheme 1d).
With the optimal reaction conditions in hand, we then
explored the substrate scope of the three-component reaction.
Results and discussion
We first carried out the reaction of quinoline N-oxide (1a) with Firstly, aryldiazonium tetrafluoroborates with various substitu-
sodium metabisulfite, and phenyl diazonium tetrafluoroborate ent groups such as methyl, tert-butyl, methoxyl, trifluoro-
(2a) in CH3CN at 30 °C for 12 hours, and the target product 3a methoxy, trifluoromethyl and halo (F, Cl and Br) were tested
was obtained in 25% yield (Table 1, entry 1). Then, some other under the standard conditions, giving the corresponding pro-
solvents such as dimethyl formamide (DMF), 1,4-dioxane, ducts in moderate to good yields (Table 2). According to the
toluene, tetrahydrofuran (THF), H2O, and 1,2-dichloroethane steric hindrance effect, the reactivities of aryldiazonium tetra-
(DCE) were studied (Table 1, entries 2–7). The yield improved fluoroborates bearing para-substituents were better than those
to 38% when the reaction was performed in 1,2-dichloroethane bearing meta- and ortho-substituents. On the other hand,
(DCE) (Table 1, entry 7). Subsequently, the amount of sodium based on the electronic characteristics, aryldiazonium tetra-
metabisulfite was investigated, and the best result was fluoroborates bearing electron-donating groups (3a–e, 3j and
obtained when 2.0 equivalents of sodium metabisulfite were 3o) reacted better than those bearing electron-withdrawing
employed (Table 1, entries 8–10). After this, the transformation groups (3f–i, 3k–n and 3p–s). Unfortunately, pyridine N-oxide
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Table 2 Substrate scope of aryldiazonium tetrafluoroboratesa,b
Scheme 2 Gram-scale synthesis.
dehalogenation process of iodoquinoline N-oxides was respon-
sible for this result. Furthermore, to demonstrate the appli-
cation value of the transformation, a gram-scale synthesis of 2-
(phenylsulfonyl)quinoline was carried out, giving the target
product in 63% yield (Scheme 2).
To study the mechanism of the three-component reaction,
some control experiments were conducted (Scheme 3). First of
all, the transformation was completely suppressed by using
TEMPO as the radical inhibitor (Scheme 3a). Further investi-
gations found that triphenylethylene 5 and (2-(phenylsulfonyl)
ethene-1,1-diyl)dibenzene 6 were obtained in 15% and 29%
yields, respectively, by using 1,1-diphenylethylene as the
radical trapping reagent. These results implied that a radical
pathway was involved in this transformation (Scheme 3b).
Meanwhile, the results of 1H NMR and HRMS revealed that
benzenesulfonic acid was generated during the transformation
(Scheme 3c).
a Reaction conditions: 1a (0.2 mmol), Na2S2O5 (2.0 equiv.), 2 (1.5
equiv.), DCE (2.0 mL), 50 °C, N2, 12 h. b Isolated yields.
(1j) and quinoxaline N-oxide (1k) could not be converted into
the corresponding product under the standard conditions (see
the ESI†).
Next, the transformations of different aryldiazonium tetra-
fluoroborates with quinoline N-oxides bearing various syn-
thetically useful functional groups were studied (Table 3). In
general, all the substrates could be converted into the corres-
ponding products smoothly. Quinoline N-oxides with common
groups such as methyl (–CH3) and methoxy (–OCH3) were well
compatible under the standard conditions, yielding the corres-
ponding products (3t, 3w, 3x, 3aa, 3ag–ak and 3ao–aq) in
acceptable yields. Isoquinoline N-oxide was also tested under
the standard conditions, and the product (3ab) was obtained
in 61% yield. Halogen-containing substrates, which could be
further functionalized, were also tolerated, giving the products
(3u, 3v, 3y, 3z, 3ac–af and 3al–3an) in 37–69% yields. It is
worth mentioning that iodoquinoline N-oxides provided the
corresponding products (3z and 3ak–am) in lower yields than
other substituted quinoline N-oxides. We suspected that the
Based on the mechanism research in previous reports21h–j,23
and the results of the above control experiments, a plausible
mechanism was proposed for the three-component reaction
(Scheme 4). Firstly, phenyldiazonium tetrafluoroborates under-
went a decomposition process to generate phenyl radical A,
which subsequently attacked Na2S2O5 to give benzene sulfonyl
radical B. Then, the benzene sulfonyl radical B reacted with
quinoline N-oxide 1a via a Minisci-like radical transformation
Table 3 Substrate scope of quinoline N-oxidesa,b
Scheme 3 Control experiments.
a Reaction conditions: 1 (0.2 mmol), Na2S2O5 (2.0 equiv.), 2 (1.5
equiv.), DCE (2.0 mL), 50 °C, N2, 12 h. b Isolated yields.
Scheme 4 Plausible mechanism.
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to provide radical intermediate C. After another molecule of (d, J = 8.1 Hz, 1H), 7.72 (ddd, J = 8.4, 6.9, 1.3 Hz, 1H),
benzene sulfonyl radical B coupled with radical intermediate C 7.62–7.57 (m, 1H), 7.54 (ddd, J = 6.6, 3.8, 1.2 Hz, 1H), 7.47
to produce intermediate D, target product 3a was obtained (dd, J = 10.4, 4.7 Hz, 2H). 13C NMR (126 MHz, CDCl3) δ 157.12,
through an aromatization process with the release of benzene- 146.46, 138.14, 137.70, 132.70, 129.97, 129.43, 128.20, 128.06,
sulfonic acid.21i
128.05, 127.84, 126.68, 116.72.
2-Tosylquinoline (3b).21h Obtained as a white solid, 75%
yield. 1H NMR (500 MHz, CDCl3) δ 8.34 (d, J = 8.5 Hz, 1H), 8.15
(dd, J = 12.7, 8.6 Hz, 2H), 8.00 (d, J = 8.2 Hz, 2H), 7.84 (d, J =
8.2 Hz, 1H), 7.78–7.71 (m, 1H), 7.62 (dd, J = 8.1, 7.0 Hz, 1H),
7.30 (d, J = 8.0 Hz, 2H), 2.36 (s, 3H). 13C NMR (126 MHz,
CDCl3) δ 157.17, 146.28, 143.73, 137.64, 134.99, 129.85, 129.19,
128.67, 128.03, 127.91, 127.65, 126.61, 116.55, 20.53.
2-((4-(tert-Butyl)phenyl)sulfonyl)quinoline (3c).21h Obtained
Conclusions
In conclusion, we reported a novel and simple approach for
the synthesis of 2-sulfonylquinolines from quinoline N-oxides,
sodium metabisulfite, and aryldiazonium tetrafluoroborates
under transition-metal- and oxidant-free conditions, giving the
corresponding products in moderate to good yields. The
control experiments revealed that a dual radical coupling
process was responsible for this transformation.
1
as a white solid, 70% yield. H NMR (500 MHz, CDCl3) δ 8.45
(d, J = 2.5 Hz, 1H), 8.10 (d, J = 8.5 Hz, 1H), 7.96 (d, J = 2.4 Hz,
1H), 7.79 (t, J = 8.0 Hz, 3H), 7.76–7.69 (m, 1H), 7.60 (t, J =
7.5 Hz, 1H), 7.55 (d, J = 8.6 Hz, 2H), 1.34 (s, 9H). 13C NMR
(126 MHz, CDCl3) δ 157.97, 145.30, 144.25, 142.05, 130.68,
128.97, 128.18, 127.38, 127.04, 126.92, 126.88, 126.76, 125.48,
34.41, 29.96.
Experimental section
General information
2-((4-Methoxyphenyl)sulfonyl)quinoline (3d).21h Obtained as
All commercial reagents were used as received. All products
were isolated by short chromatography on
1
a white solid, 66% yield. H NMR (500 MHz, CDCl3) δ 8.36 (d,
a silica gel
J = 8.5 Hz, 1H), 8.21–8.14 (m, 2H), 8.07 (d, J = 8.9 Hz, 2H), 7.87
(d, J = 8.0 Hz, 1H), 7.77 (dd, J = 11.3, 4.0 Hz, 1H), 7.65 (t, J =
7.5 Hz, 1H), 7.00 (d, J = 8.9 Hz, 2H), 3.84 (s, 3H). 13C NMR
(126 MHz, CDCl3) δ 163.91, 158.66, 147.44, 138.69, 131.31,
130.92, 130.50, 130.38, 129.07, 128.77, 127.70, 117.57, 114.41,
55.67.
(200–300 mesh) column using petroleum ether (60–90 °C) and
1
ethyl acetate. H and 13C NMR spectra were recorded using a
Bruker Advance DRX-500 spectrometer at ambient temperature
with CDCl3 as the solvent and tetramethylsilane (TMS) as the
internal standard. All chemical shift values are quoted in ppm
and coupling constants are quoted in Hz. Compounds for
HRMS were analyzed by positive mode electrospray ionization
(ESI) using an Agilent 6530 QTOF mass spectrometer.
2-((4-(Trifluoromethoxy)phenyl)sulfonyl)quinoline
(3e).21g
Obtained as a white solid, 62% yield. 1H NMR (500 MHz,
CDCl3) δ 8.42 (s, 1H), 8.22 (dd, J = 8.7, 6.7 Hz, 3H), 8.17 (d, J =
8.6 Hz, 1H), 7.90 (d, J = 8.2 Hz, 1H), 7.84–7.78 (m, 1H), 7.69 (t,
J = 7.2 Hz, 1H), 7.36 (d, J = 8.4 Hz, 2H). 13C NMR (126 MHz,
CDCl3) δ 157.72, 153.10, 147.50, 138.92, 137.27, 131.42, 131.19,
130.39, 129.42, 128.95, 127.77, 120.77, 120.19 (q, J = 259.6 Hz),
117.54.
General experimental procedure for synthesis of products 3
A solution of quinoline N-oxides 1 (0.2 mmol), sodium metabi-
sulfite (2.0 equiv.), and aryldiazonium tetrafluoroborates 2 (1.5
equiv.) in DCE (2.0 mL) was stirred under a N2 atmosphere at
50 °C for 12 hours. After the conversion was completed as indi-
cated by TLC, the mixture was diluted with water and extracted
with EA. The collected organic solvent was then evaporated
under reduced pressure. The residue was purified directly by
flash column chromatography (EA/PE, 1 : 5) to give products 3.
2-((4-(Trifluoromethyl)phenyl)sulfonyl)quinoline (3f).21h
Obtained as a white solid, 52% yield. 1H NMR (500 MHz,
CDCl3) δ 8.42 (d, J = 8.5 Hz, 1H), 8.29 (d, J = 8.2 Hz, 2H), 8.24
(d, J = 8.5 Hz, 1H), 8.15 (d, J = 8.6 Hz, 1H), 7.90 (d, J = 8.2 Hz,
1H), 7.81 (d, J = 8.1 Hz, 3H), 7.69 (t, J = 7.5 Hz, 1H). 13C NMR
(126 MHz, CDCl3) δ 156.31, 146.47, 141.61, 137.98, 134.28 (q,
J = 31.5 Hz), 130.25, 129.32, 128.70, 128.52, 127.96, 126.76,
125.14 (q, J = 3.8 Hz), 122.13 (q, J = 273.4 Hz), 116.55.
General experimental procedure for gram-scale synthesis of
product 3a
A solution of quinoline N-oxides 1a (7.0 mmol), sodium meta-
2-((4-Fluorophenyl)sulfonyl)quinoline (3g).21h Obtained as a
bisulfite (2.0 equiv.), and benzenediazonium tetrafluorobo- white solid, 58% yield. 1H NMR (500 MHz, CDCl3) δ 8.39 (d, J =
rates 2a (1.5 equiv.) in DCE (30 mL) was stirred under a N2 8.5 Hz, 1H), 8.20 (d, J = 8.5 Hz, 1H), 8.18–8.12 (m, 3H), 7.88
atmosphere at 50 °C for 12 hours. After the conversion was (d, J = 8.1 Hz, 1H), 7.78 (ddd, J = 8.4, 6.9, 1.4 Hz, 1H), 7.66
completed as indicated by TLC, the mixture was diluted with (ddd, J = 8.1, 7.0, 1.0 Hz, 1H), 7.20 (t, J = 8.6 Hz, 2H). 13C NMR
water and extracted with EA. The collected organic solvent was (126 MHz, CDCl3) δ 164.86 (d, J = 257.0 Hz), 156.86, 146.35,
then evaporated under reduced pressure. The residue was puri- 137.83, 133.93 (d, J = 3.8 Hz), 130.92 (d, J = 10.1 Hz), 130.06,
fied directly by flash column chromatography (EA/PE, 1 : 5) to 129.23, 128.26, 127.79, 126.70, 116.41, 115.37 (d, J = 22.7 Hz).
give product 3a.
2-((4-Chlorophenyl)sulfonyl)quinoline (3h).21h Obtained as a
2-(Phenylsulfonyl)quinoline (3a).21h Obtained as a white white solid, 62% yield. 1H NMR (500 MHz, CDCl3) δ 8.39 (d, J =
solid, 72% yield. 1H NMR (500 MHz, CDCl3) δ 8.31 (d, J = 8.5 Hz, 1H), 8.20 (d, J = 8.5 Hz, 1H), 8.15 (d, J = 8.6 Hz, 1H),
8.5 Hz, 1H), 8.15 (d, J = 8.5 Hz, 1H), 8.12–8.05 (m, 3H), 7.81 8.08 (d, J = 8.5 Hz, 2H), 7.89 (d, J = 8.2 Hz, 1H), 7.80 (t, J = 7.7 Hz,
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1H), 7.67 (t, J = 7.5 Hz, 1H), 7.51 (d, J = 8.5 Hz, 2H). 13C NMR δ 157.27, 148.81, 138.38, 138.28, 135.07, 134.86, 132.69,
(126 MHz, CDCl3) δ 157.80, 147.47, 140.60, 138.91, 137.52, 130.93, 130.35, 129.25, 129.04, 129.01, 127.81, 127.77, 118.69.
131.17, 130.59, 130.36, 129.44, 129.39, 128.91, 127.77, 117.52.
2-(m-Tolylsulfonyl)quinoline (3o).3e Obtained as a white
2-((4-Bromophenyl)sulfonyl)quinoline (3i).21h Obtained as a solid, 69% yield. 1H NMR (600 MHz, CDCl3) δ 8.42 (d, J =
white solid, 64% yield. 1H NMR (500 MHz, CDCl3) δ 8.33 (d, J = 8.5 Hz, 1H), 8.29 (t, J = 1.7 Hz, 1H), 8.22 (d, J = 8.5 Hz, 1H),
8.5 Hz, 1H), 8.14 (d, J = 8.5 Hz, 1H), 8.08 (d, J = 8.6 Hz, 1H), 8.19 (d, J = 8.6 Hz, 1H), 8.10–8.08 (m, 1H), 7.91 (d, J = 8.2 Hz,
7.94 (d, J = 8.6 Hz, 2H), 7.82 (d, J = 8.0 Hz, 1H), 7.75–7.71 (m, 1H), 7.84–7.80 (m, 1H), 7.75–7.72 (m, 1H), 7.71–7.68 (m, 1H),
1H), 7.63–7.58 (m, 3H). 13C NMR (126 MHz, CDCl3) δ 156.70, 2.55 (s, 3H). 13C NMR (126 MHz, CDCl3) δ 155.54, 145.49,
146.44, 137.86, 137.01, 131.38, 130.14, 129.61, 129.33, 128.36, 138.82, 136.89, 133.29, 131.86, 129.16, 128.42, 128.32, 127.42,
128.22, 127.88, 126.73, 116.49.
127.07, 126.94, 125.73, 125.25, 115.63, 20.83.
2-((3-(Trifluoromethyl)phenyl)sulfonyl)quinoline (3p). Obtained
2-(o-Tolylsulfonyl)quinoline (3j).21g Obtained as a white
1
solid, 65% yield. H NMR (600 MHz, CDCl3) δ 8.40 (d, J = 8.5 as a white solid, 49% yield. M.p. 109–110 °C. 1H NMR
Hz, 1H), 8.32 (dd, J = 7.9, 1.2 Hz, 1H), 8.19 (d, J = 8.5 Hz, 1H), (500 MHz, CDCl3) δ 8.38–8.31 (m, 2H), 8.28 (d, J = 7.9 Hz, 1H),
8.12 (d, J = 8.2 Hz, 1H), 7.90 (d, J = 8.3 Hz, 1H), 7.78 (ddd, J = 8.16 (d, J = 8.5 Hz, 1H), 8.05 (d, J = 8.6 Hz, 1H), 7.82 (d, J =
8.4, 6.9, 1.4 Hz, 1H), 7.67 (ddd, J = 8.1, 6.9, 1.1 Hz, 1H), 7.51 8.2 Hz, 1H), 7.78 (d, J = 7.8 Hz, 1H), 7.72 (ddd, J = 8.4, 7.0, 1.3
(td, J = 7.6, 1.4 Hz, 1H), 7.43 (t, J = 7.7 Hz, 1H), 7.26 (d, J = 5.7 Hz, 1H), 7.64–7.57 (m, 2H). 13C NMR (126 MHz, CDCl3) δ
Hz, 1H), 2.57 (s, 3H). 13C NMR (126 MHz, CDCl3) δ 158.28, 156.35, 146.45, 139.25, 138.00, 131.47, 130.72 (q, J = 34.80 Hz),
147.22, 139.16, 138.60, 137.17, 133.91, 132.46, 130.96, 130.68, 130.24, 129.38 (q, J = 3.8 Hz), 129.29, 128.80, 128.49, 127.95,
130.46, 129.18, 128.92, 127.72, 126.41, 117.77, 20.74.
126.76, 125.24 (q, J = 3.8 Hz), 1122.14 (q, J = 273.4 Hz), 116.46.
2-((2-(Trifluoromethyl)phenyl)sulfonyl)quinoline (3k). Obtained HRMS (ESI) calculated for C16H10F3NO2S+: 338.0457 [M + H]+,
as a white solid, 44% yield. M.p. 117–118 °C. 1H NMR found: 338.0451.
(500 MHz, CDCl3) δ 8.64 (d, J = 7.9 Hz, 1H), 8.35 (d, J = 8.6 Hz,
2-((3-Fluorophenyl)sulfonyl)quinoline (3q). Obtained as a
1
1H), 8.18 (d, J = 8.6 Hz, 1H), 7.89 (d, J = 8.6 Hz, 1H), 7.82 (dd, white solid, 65% yield. M.p. 128–129 °C. H NMR (500 MHz,
J = 14.4, 7.5 Hz, 2H), 7.77 (d, J = 6.8 Hz, 1H), 7.72 (t, J = 7.6 Hz, CDCl3) δ 8.33 (d, J = 8.5 Hz, 1H), 8.14 (d, J = 8.5 Hz, 1H), 8.10
1H), 7.67 (t, J = 7.0 Hz, 1H), 7.61–7.56 (m, 1H). 13C NMR (d, J = 8.6 Hz, 1H), 7.87 (d, J = 7.9 Hz, 1H), 7.82 (d, J = 8.2 Hz,
(126 MHz, CDCl3) δ 157.42, 145.98, 137.51, 135.99, 133.17, 1H), 7.80–7.77 (m, 1H), 7.74 (ddd, J = 8.4, 6.9, 1.3 Hz, 1H),
132.79, 131.19, 129.86, 129.12, 128.37 (q, J = 34.0 Hz), 128.13, 7.63–7.58 (m, 1H), 7.45 (td, J = 8.1, 5.2 Hz, 1H), 7.23 (td, J =
127.94, 127.17 (q, J = 6.3 Hz), 126.79, 121.53 (q, J = 274.7 Hz), 8.3, 1.9 Hz, 1H). 13C NMR (126 MHz, CDCl3) δ 161.35 (d, J =
115.97. HRMS (ESI) calculated for C16H10F3NO2S+: 338.0457 253.3 Hz), 156.55, 146.47, 140.13 (d, J = 7.8 Hz), 137.87, 130.15,
[M + H]+, found: 338.0459.
129.82 (d, J = 7.8 Hz), 129.40, 128.41, 127.93, 126.73, 123.87
2-((2-Fluorophenyl)sulfonyl)quinoline (3l). Obtained as a (d, J = 2.5 Hz), 120.00 (d, J = 21.4 Hz), 116.63, 115.41 (d, J =
1
white solid, 52% yield. M.p. 121–122 °C. H NMR (500 MHz, 21.4 Hz). HRMS (ESI) calculated for C15H10FNO2S+: 288.0489
CDCl3) δ 8.37 (d, J = 8.6 Hz, 1H), 8.24 (d, J = 8.6 Hz, 1H), [M + H]+, found: 288.0481.
8.22–8.18 (m, 1H), 8.04 (d, J = 8.6 Hz, 1H), 7.84 (d, J = 8.1 Hz,
2-((3-Chlorophenyl)sulfonyl)quinoline (3r).21h Obtained as a
1H), 7.70 (ddd, J = 8.4, 6.9, 1.3 Hz, 1H), 7.63–7.58 (m, 1H), 7.55 white solid, 57% yield. 1H NMR (500 MHz, CDCl3) δ 8.34 (d, J =
(ddd, J = 7.5, 4.6, 2.1 Hz, 1H), 7.36–7.29 (m, 1H), 7.03 (t, J = 9.1 8.5 Hz, 1H), 8.15 (d, J = 8.5 Hz, 1H), 8.11 (d, J = 8.6 Hz, 1H),
Hz, 1H). 13C NMR (126 MHz, CDCl3) δ 158.62 (d, J = 258.3 Hz), 8.06 (t, J = 1.9 Hz, 1H), 7.97 (d, J = 7.9 Hz, 1H), 7.83 (d,
156.58, 146.26, 137.71, 135.34 (d, J = 8.8 Hz), 130.13, 129.97, J = 8.2 Hz, 1H), 7.76–7.72 (m, 1H), 7.63–7.59 (m, 1H),
129.36, 128.30, 128.15, 126.75, 126.13 (d, J = 13.9 Hz), 123.56 7.52–7.49 (m, 1H), 7.41 (t, J = 7.9 Hz, 1H). 13C NMR
(d, J = 3.8 Hz), 116.89 (d, J = 2.5 Hz), 115.97 (d, J = 21.4 Hz). (126 MHz, CDCl3) δ 156.54, 146.48, 139.82, 137.89, 134.29,
HRMS (ESI) calculated for C15H10FNO2S+: 288.0489 [M + H]+, 132.86, 130.15, 129.42, 129.31, 128.41, 128.06, 127.94, 126.73,
found: 288.0484.
126.24, 116.62.
2-((2-Chlorophenyl)sulfonyl)quinoline (3m).21h Obtained
2-((3-Bromophenyl)sulfonyl)quinoline (3s).21g Obtained as a
as a white solid, 54% yield. 1H NMR (500 MHz, CDCl3) white solid, 60% yield. 1H NMR (600 MHz, CDCl3) δ 8.34 (d, J =
δ 8.46–8.42 (m, 1H), 8.37 (d, J = 8.6 Hz, 1H), 8.27 (d, J = 8.6 Hz, 8.5 Hz, 1H), 8.21 (t, J = 1.7 Hz, 1H), 8.14 (d, J = 8.5 Hz, 1H),
1H), 7.98 (d, J = 8.5 Hz, 1H), 7.85 (d, J = 8.2 Hz, 1H), 7.71–7.67 8.11 (d, J = 8.6 Hz, 1H), 8.03–8.00 (m, 1H), 7.83 (d, J = 8.2 Hz,
(m, 1H), 7.60 (t, J = 7.5 Hz, 1H), 7.53–7.48 (m, 2H), 7.37–7.32 1H), 7.76–7.73 (m, 1H), 7.67–7.65 (m, 1H), 7.63–7.60 (m, 1H),
(m, 1H). 13C NMR (126 MHz, CDCl3) δ 156.40, 146.22, 137.34, 7.35 (t, J = 8.0 Hz, 1H). 13C NMR (126 MHz, CDCl3) δ 156.52,
135.75, 133.87, 132.09, 131.20, 130.52, 129.90, 129.31, 128.22, 146.48, 139.95, 137.90, 135.77, 130.85, 130.16, 129.53, 129.41,
128.02, 126.77, 126.17, 117.39.
128.42, 127.94, 126.73, 126.70, 122.02, 116.62.
2-((2-Bromophenyl)sulfonyl)quinoline (3n).21f Obtained as a
3-Methyl-2-(phenylsulfonyl)quinoline (3t).21c Obtained as a
1
white solid, 58% yield. H NMR (500 MHz, CDCl3) δ 8.55 (dd, white solid, 67% yield. 1H NMR (500 MHz, CDCl3) δ 8.07 (dd, J =
J = 7.8, 1.5 Hz, 1H), 8.44 (d, J = 8.5 Hz, 1H), 8.35 (d, J = 8.6 Hz, 4.0, 3.2 Hz, 3H), 7.88 (d, J = 8.5 Hz, 1H), 7.79–7.75 (m, 1H),
1H), 8.04 (d, J = 8.6 Hz, 1H), 7.92 (d, J = 8.2 Hz, 1H), 7.76 (dd, 7.70–7.63 (m, 2H), 7.61–7.55 (m, 3H), 2.88 (s, 3H). 13C NMR
J = 11.3, 4.1 Hz, 1H), 7.69 (d, J = 7.1 Hz, 1H), 7.63 (t, J = 7.9 Hz, (126 MHz, CDCl3) δ 156.94, 144.67, 139.88, 138.79, 133.55, 129.97,
2H), 7.49 (td, J = 7.7, 1.6 Hz, 1H). 13C NMR (126 MHz, CDCl3) 129.80, 129.49, 129.16, 129.03, 128.67, 128.59, 126.71, 18.80.
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3-Bromo-2-(phenylsulfonyl)quinoline (3u). Obtained as a
1-(Phenylsulfonyl)isoquinoline (3ab).21c Obtained as a white
white solid, 65% yield. M.p. 132–133 °C. H NMR (500 MHz, solid, 61% yield. 1H NMR (500 MHz, CDCl3) δ 9.20–9.13 (m,
CDCl3) δ 8.52 (s, 1H), 8.13–8.06 (m, 2H), 7.93 (d, J = 8.4 Hz, 1H), 8.42 (d, J = 5.5 Hz, 1H), 8.14–8.05 (m, 2H), 7.93–7.87 (m,
1H), 7.79–7.73 (m, 2H), 7.70–7.64 (m, 2H), 7.57 (t, J = 7.8 Hz, 1H), 7.82–7.73 (m, 3H), 7.64 (t, J = 7.4 Hz, 1H), 7.56 (t, J = 7.7
2H). 13C NMR (126 MHz, CDCl3) δ 153.31, 143.36, 141.89, Hz, 2H). 13C NMR (126 MHz, CDCl3) δ 157.07, 140.57, 139.13,
136.91, 132.83, 130.07, 129.17, 129.07, 128.74, 128.52, 127.66, 137.80, 133.71, 131.19, 129.30, 129.23, 128.91, 127.60, 125.30,
125.49, 110.27. HRMS (ESI) calculated for C15H10BrNO2S+: 125.08, 124.38.
1
347.9689 [M + H]+, found: 347.9682.
4-Chloro-2-((4-chlorophenyl)sulfonyl)quinoline
(3ac).
4-Chloro-2-(phenylsulfonyl)quinoline (3v). Obtained as a Obtained as a white solid, 65% yield. M.p. 176–177 °C. 1H
1
white solid, 69% yield. M.p. 162–163 °C. H NMR (500 MHz, NMR (500 MHz, CDCl3) δ 8.29 (s, 1H), 8.27 (dd, J = 8.5, 0.9 Hz,
CDCl3) δ 8.30 (s, 1H), 8.27 (d, J = 8.4 Hz, 1H), 8.19 (d, J = 1H), 8.17 (d, J = 8.5 Hz, 1H), 8.08 (d, J = 8.7 Hz, 2H), 7.88–7.83
8.5 Hz, 1H), 8.16–8.13 (m, 2H), 7.84 (t, J = 7.7 Hz, 1H), 7.76 (t, (m, 1H), 7.80–7.75 (m, 1H), 7.53 (d, J = 8.7 Hz, 2H). 13C NMR
J = 7.6 Hz, 1H), 7.63 (t, J = 7.4 Hz, 1H), 7.56 (t, J = 7.7 Hz, 2H). (126 MHz, CDCl3) δ 157.63, 148.15, 145.45, 140.94, 137.01,
13C NMR (126 MHz, CDCl3) δ 156.92, 147.14, 144.27, 137.62, 131.98, 130.79, 130.69, 130.38, 129.55, 127.16, 124.29, 117.80.
132.99, 130.80, 129.83, 129.21, 128.18, 128.14, 126.08, 123.21, HRMS (ESI) calculated for C15H9Cl2NO2S+: 337.9804 [M + H]+,
116.97. HRMS (ESI) calculated for C15H10ClNO2S+: 304.0194 found: 337.9800.
[M + H]+, found: 304.0191.
2-((4-Bromophenyl)sulfonyl)-4-chloroquinoline
(3ad).
6-Methyl-2-(phenylsulfonyl)quinoline (3w). Obtained as a Obtained as a white solid, 68% yield. M.p. 186–187 °C. 1H
1
white solid, 72% yield. M.p. 130–131 °C. H NMR (500 MHz, NMR (500 MHz, CDCl3) δ 8.32–8.26 (m, 2H), 8.17 (d, J = 8.5 Hz,
CDCl3) δ 8.26 (d, J = 8.5 Hz, 1H), 8.18–8.10 (m, 3H), 8.05 (d, J = 1H), 8.08 (d, J = 8.7 Hz, 2H), 7.88–7.84 (m, 1H), 7.80–7.75 (m,
8.5 Hz, 1H), 7.62–7.56 (m, 3H), 7.52 (t, J = 7.6 Hz, 2H), 2.54 (s, 1H), 7.53 (d, J = 8.7 Hz, 2H). 13C NMR (126 MHz, CDCl3) δ
3H). 13C NMR (126 MHz, CDCl3) δ 156.09, 145.08, 138.68, 157.63, 148.16, 145.46, 140.94, 137.01, 131.97, 130.80, 130.69,
138.30, 136.80, 132.64, 132.58, 132.36, 128.98, 128.01, 127.91, 130.38, 129.56, 127.17, 124.30, 117.81. HRMS (ESI) calculated
125.38, 116.77, 20.76. HRMS (ESI) calculated for C16H13NO2S+: for C15H9BrClNO2S+: 381.9299 [M + H]+, found: 381.9293.
284.0740 [M + H]+, found: 284.0734.
5-Bromo-2-(m-tolylsulfonyl)quinoline (3ae). Obtained as a
1
6-Methoxy-2-(phenylsulfonyl)quinoline (3x).21c Obtained as white solid, 57% yield. M.p. 176–177 °C. H NMR (500 MHz,
1
a white solid, 63% yield. H NMR (500 MHz, CDCl3) δ 8.21 (d, CDCl3) δ 8.77 (d, J = 8.8 Hz, 1H), 8.33–8.27 (m, 1H), 8.16 (d, J =
J = 8.6 Hz, 1H), 8.15–8.09 (m, 3H), 8.03 (d, J = 9.3 Hz, 1H), 7.57 8.6 Hz, 1H), 8.00–7.88 (m, 3H), 7.68–7.61 (m, 1H), 7.47–7.40
(t, J = 7.4 Hz, 1H), 7.51 (t, J = 7.6 Hz, 2H), 7.40 (dd, J = 9.3, 2.7 (m, 2H), 2.43 (s, 3H). 13C NMR (126 MHz, CDCl3) δ 159.08,
Hz, 1H), 7.07 (d, J = 2.7 Hz, 1H), 3.92 (s, 3H). 13C NMR 148.17, 139.48, 138.65, 138.60, 134.78, 132.77, 131.17, 130.35,
(126 MHz, CDCl3) δ 158.81, 154.34, 142.59, 138.47, 135.81, 129.33, 129.06, 128.36, 126.29, 121.88, 118.94, 21.34. HRMS
132.50, 130.74, 129.39, 127.99, 127.78, 123.29, 117.23, 103.57, (ESI) calculated for C16H12BrNO2S+: 361.9845 [M + H]+, found:
54.69.
6-Chloro-2-(phenylsulfonyl)quinoline (3y).21c Obtained as a
361.9850.
5-Bromo-2-((4-bromophenyl)sulfonyl)quinoline
(3af).
white solid, 66% yield. 1H NMR (500 MHz, CDCl3) δ 8.30 (d, J = Obtained as a white solid, 62% yield. M.p. 187–188 °C. 1H
8.6 Hz, 1H), 8.23 (d, J = 8.6 Hz, 1H), 8.17–8.11 (m, 2H), 8.10 (d, J NMR (500 MHz, CDCl3) δ 8.79 (d, J = 8.8 Hz, 1H), 8.29 (d, J =
= 9.1 Hz, 1H), 7.86 (d, J = 2.2 Hz, 1H), 7.71 (dd, J = 9.1, 2.3 Hz, 8.8 Hz, 1H), 8.12 (d, J = 8.6 Hz, 1H), 8.00 (d, J = 8.6 Hz, 2H),
1H), 7.62 (t, J = 7.4 Hz, 1H), 7.55 (t, J = 7.6 Hz, 2H). 13C NMR 7.97–7.92 (m, 1H), 7.69 (d, J = 8.6 Hz, 2H), 7.68–7.62 (m, 1H).
(126 MHz, CDCl3) δ 157.40, 144.77, 137.81, 136.79, 134.32, 13C NMR (126 MHz, CDCl3) δ 158.63, 148.13, 138.80, 137.69,
132.86, 131.09, 130.89, 128.35, 128.13, 128.08, 125.33, 117.63.
132.95, 132.50, 131.36, 130.71, 130.23, 129.51, 128.42, 121.93,
6-Iodo-2-(phenylsulfonyl)quinoline (3z). Obtained as a white 118.62. HRMS (ESI) calculated for C15H9Br2NO2S+: 425.8794
1
solid, 49% yield. M.p. 142–143 °C. H NMR (500 MHz, CDCl3) [M + H]+, found: 425.8797.
δ 8.14 (d, J = 8.6 Hz, 1H), 8.05 (dt, J = 9.0, 3.4 Hz, 3H), 7.96 (d, J
6-Methyl-2-tosylquinoline (3ag).21c Obtained as a white
1
= 9.3 Hz, 1H), 7.50 (t, J = 7.4 Hz, 1H), 7.44 (t, J = 7.6 Hz, 2H), solid, 75% yield. H NMR (500 MHz, CDCl3) δ 8.25 (d, J = 8.5
7.33 (dd, J = 9.3, 2.7 Hz, 1H), 7.00 (d, J = 2.7 Hz, 1H). 13C NMR Hz, 1H), 8.15 (d, J = 8.5 Hz, 1H), 8.06 (d, J = 8.5 Hz, 1H), 8.01
(126 MHz, CDCl3) δ 157.81, 153.34, 141.59, 137.47, 134.81, (d, J = 8.3 Hz, 2H), 7.61 (d, J = 8.9 Hz, 2H), 7.32 (d, J = 8.1 Hz,
131.50, 129.74, 128.39, 126.99, 126.78, 122.29, 116.23, 95.68. 2H), 2.55 (s, 3H), 2.40 (s, 3H). 13C NMR (126 MHz, CDCl3) δ
HRMS (ESI) calculated for C15H10INO2S+: 395.9550 [M + H]+, 157.45, 146.13, 144.67, 139.60, 137.78, 136.38, 133.33, 130.06,
found: 395.9555.
129.75, 129.01, 128.93, 126.42, 117.78, 21.82, 21.66.
2-((4-Bromophenyl)sulfonyl)-6-methylquinoline
8-Methyl-2-(phenylsulfonyl)quinoline (3aa).21c Obtained as a
(3ah).21c
white solid, 74% yield. 1H NMR (500 MHz, CDCl3) δ 8.33 (d, J = Obtained as a white solid, 67% yield. 1H NMR (500 MHz,
8.5 Hz, 1H), 8.24–8.14 (m, 3H), 7.68 (d, J = 8.1 Hz, 1H), CDCl3) δ 8.28 (d, J = 8.5 Hz, 1H), 8.15 (d, J = 8.5 Hz, 1H), 8.03
7.63–7.57 (m, 2H), 7.53 (dd, J = 16.2, 8.0 Hz, 3H), 2.65 (s, 3H). (d, J = 8.5 Hz, 1H), 8.00 (d, J = 8.5 Hz, 2H), 7.67 (d, J = 8.5 Hz,
13C NMR (126 MHz, CDCl3) δ 156.05, 145.31, 137.84, 137.73, 2H), 7.62 (d, J = 9.0 Hz, 2H), 2.55 (s, 3H). 13C NMR (126 MHz,
137.34, 132.60, 129.88, 128.33, 127.94, 127.81, 127.77, 124.51, CDCl3) δ 156.77, 146.14, 139.93, 138.30, 137.98, 133.58, 132.38,
115.66, 16.41.
130.57, 129.96, 129.10, 129.03, 126.49, 117.61, 21.85.
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6-Methoxy-2-(m-tolylsulfonyl)quinoline (3ai). Obtained as a
8-Methyl-2-(o-tolylsulfonyl)quinoline (3ao). Obtained as a
1
1
white solid, 50% yield. M.p. 195–196 °C. H NMR (500 MHz, white solid, 59% yield. M.p. 132–133 °C. H NMR (500 MHz,
CDCl3) δ 8.22 (d, J = 8.6 Hz, 1H), 8.15 (d, J = 8.6 Hz, 1H), 8.07 CDCl3) δ 8.36 (d, J = 8.5 Hz, 1H), 8.27 (dd, J = 7.9, 0.9 Hz, 1H),
(d, J = 9.3 Hz, 1H), 7.92 (d, J = 8.9 Hz, 2H), 7.45–7.36 (m, 3H), 8.20 (d, J = 8.5 Hz, 1H), 7.71 (d, J = 8.0 Hz, 1H), 7.59 (d, J = 6.8
7.09 (d, J = 2.6 Hz, 1H), 3.94 (s, 3H), 2.41 (s, 3H). 13C NMR Hz, 1H), 7.55–7.49 (m, 2H), 7.41 (t, J = 7.5 Hz, 1H), 7.28 (d, J =
(126 MHz, CDCl3) δ 159.85, 155.55, 143.69, 139.40, 139.31, 7.6 Hz, 1H), 2.65 (s, 3H), 2.58 (s, 3H). 13C NMR (126 MHz,
136.83, 134.39, 131.89, 130.45, 129.09, 128.94, 126.02, 124.29, CDCl3) δ 157.30, 146.16, 139.58, 138.80, 138.50, 137.14, 133.77,
118.38, 104.62, 55.75, 21.33. HRMS (ESI) calculated for 132.31, 130.96, 130.87, 129.02, 128.98, 126.27, 125.59, 116.91,
C17H15NO3S+: 314.0846 [M + H]+, found: 314.0843.
2-((4-Bromophenyl)sulfonyl)-6-methoxyquinoline (3aj). Obtained [M + H]+, found: 298.0890.
as a white solid, 58% yield. M.p. 201–202 °C. 1H NMR
8-Methyl-2-tosylquinoline (3ap). Obtained as a white solid,
20.96, 17.44. HRMS (ESI) calculated for C17H15NO2S+: 298.0896
1
(500 MHz, CDCl3) δ 8.24 (d, J = 8.6 Hz, 1H), 8.15 (d, J = 8.5 Hz, 70% yield. M.p. 125–126 °C. H NMR (500 MHz, CDCl3) δ 8.32
1H), 8.03 (d, J = 9.3 Hz, 1H), 7.99 (d, J = 8.6 Hz, 2H), 7.67 (d, J = (d, J = 8.5 Hz, 1H), 8.20 (d, J = 8.5 Hz, 1H), 8.06 (d, J = 8.1 Hz,
8.6 Hz, 2H), 7.44 (dd, J = 9.3, 2.7 Hz, 1H), 7.10 (d, J = 2.7 Hz, 2H), 7.68 (d, J = 8.1 Hz, 1H), 7.59 (d, J = 6.8 Hz, 1H), 7.51 (t, J =
1H), 3.95 (s, 3H). 13C NMR (126 MHz, CDCl3) δ 160.00, 155.07, 7.6 Hz, 1H), 7.34 (d, J = 8.0 Hz, 2H), 2.68 (s, 3H), 2.41 (s, 3H).
143.71, 138.49, 136.93, 132.37, 131.82, 130.54, 130.48, 129.00, 13C NMR (126 MHz, CDCl3) δ 157.38, 146.44, 144.69, 138.72,
124.53, 118.11, 104.61, 55.77. HRMS (ESI) calculated for 138.43, 136.00, 130.88, 129.52, 129.43, 128.92, 128.84, 125.56,
C16H12BrNO3S+: 377.9794 [M + H]+, found: 377.9796.
116.75, 21.68, 17.53. HRMS (ESI) calculated for C17H15NO2S+:
6-Methoxy-2-((4-(trifluoromethyl)phenyl)sulfonyl)quinoline 298.0896 [M + H]+, found: 298.0888.
(3ak). Obtained as a white solid, 53% yield. M.p. 190–191 °C.
2-((4-Fluorophenyl)sulfonyl)-8-methylquinoline (3aq). Obtained
1H NMR (500 MHz, CDCl3) δ 8.26 (dd, J = 8.2, 4.2 Hz, 3H), 8.18 as a white solid, 67% yield. M.p. 117–118 °C. 1H NMR (500 MHz,
(d, J = 8.5 Hz, 1H), 8.03 (d, J = 9.3 Hz, 1H), 7.80 (d, J = 8.2 Hz, CDCl3) δ 8.35 (d, J = 8.5 Hz, 1H), 8.26–8.17 (m, 3H), 7.71 (d, J =
2H), 7.47–7.41 (m, 1H), 7.10 (d, J = 2.2 Hz, 1H), 3.95 (s, 3H). 8.1 Hz, 1H), 7.61 (d, J = 7.0 Hz, 1H), 7.56–7.50 (m, 1H), 7.22 (dd,
13C NMR (126 MHz, CDCl3) δ 160.12, 154.61, 143.75, 143.08, J = 20.7, 12.0 Hz, 2H), 2.65 (s, 3H). 13C NMR (126 MHz, CDCl3) δ
137.01, 135.13 (q, J = 32.8 Hz), 131.80, 130.65, 129.53, 126.13 165.99 (d, J = 257.0 Hz), 157.00, 148.29, 146.35, 138.92, 138.32,
(q, J = 2.5 Hz), 124.67, 123.19 (q, J = 273.4 Hz), 118.21, 104.61, 132.32 (d, J = 10.1 Hz), 131.07, 129.10, 128.92, 125.63, 116.54,
55.79. HRMS (ESI) calculated for C17H12F3NO3S+: 368.0563 [M 116.15 (d, J = 22.7 Hz), 17.49. HRMS (ESI) calculated for
+ H]+, found: 368.0560.
6-Iodo-2-(o-tolylsulfonyl)quinoline (3al). Obtained as a white
C16H12FNO2S+: 302.0646 [M + H]+, found: 302.0649.
Ethene-1,1,2-triyltribenzene (5).26 Obtained as
a
yellow
1
1
solid, 37% yield. M.p. 149–150 °C. H NMR (500 MHz, CDCl3) liquid, 18% yield. H NMR (500 MHz, CDCl3) δ 7.34–7.27 (m,
δ 8.28 (d, J = 1.8 Hz, 1H), 8.25 (d, J = 8.6 Hz, 1H), 8.20 (d, J = 8H), 7.23–7.18 (m, 2H), 7.15–7.09 (m, 3H), 7.04–7.01 (m, 2H),
8.6 Hz, 1H), 8.03–7.98 (m, 3H), 7.87 (d, J = 9.0 Hz, 1H), 7.34 (d, 6.97 (s, 1H). 13C NMR (126 MHz, CDCl3) δ 143.45, 142.60,
J = 8.2 Hz, 2H), 2.41 (s, 3H). 13C NMR (126 MHz, CDCl3) δ 140.37, 137.40, 130.40, 129.56, 128.64, 128.22, 128.18, 127.97,
158.91, 146.34, 145.03, 139.80, 137.41, 136.49, 135.82, 131.77, 127.62, 127.52, 127.42, 126.75.
131.53, 130.42, 130.17, 129.85, 129.15, 118.47, 95.57, 21.69.
HRMS (ESI) calculated for C16H12INO2S+: 409.9706 [M + H]+, as a yellow liquid, 29% yield. 1H NMR (500 MHz, CDCl3) δ 7.58
found: 409.9705. (dd, J = 8.3, 1.1 Hz, 2H), 7.46 (t, J = 7.5 Hz, 1H), 7.38–7.31 (m,
(2-(Phenylsulfonyl)ethene-1,1-diyl)dibenzene (6).27 Obtained
2-((4-Chlorophenyl)sulfonyl)-6-iodoquinoline (3am). Obtained 4H), 7.27 (dd, J = 12.1, 7.6 Hz, 4H), 7.22–7.17 (m, 2H),
as a white solid, 42% yield. M.p. 152–153 °C. 1H NMR 7.09–7.04 (m, 2H), 7.03 (s, 1H). 13C NMR (126 MHz, CDCl3) δ
(500 MHz, CDCl3) δ 8.30 (d, J = 1.8 Hz, 1H), 8.28 (d, J = 8.6 Hz, 155.27, 141.49, 139.10, 135.50, 132.93, 130.41, 129.80, 128.94,
1H), 8.21 (d, J = 8.6 Hz, 1H), 8.07 (d, J = 8.7 Hz, 2H), 8.03 (dd, J 128.79, 128.75, 128.66, 128.26, 127.91, 127.65.
= 9.0, 1.9 Hz, 1H), 7.85 (d, J = 9.0 Hz, 1H), 7.52 (d, J = 8.7 Hz,
2H). 13C NMR (126 MHz, CDCl3) δ 160.07, 155.14, 143.78,
Conflicts of interest
138.55, 136.99, 132.43, 131.89, 130.61, 130.55, 129.07, 124.59,
118.18, 95.57. HRMS (ESI) calculated for C15H9ClINO2S+:
There are no conflicts to declare.
408.0933 [M + H]+, found: 408.0931.
2-((4-Fluorophenyl)sulfonyl)-6-iodoquinoline (3an). Obtained
as a white solid, 47% yield. M.p. 141–142 °C. 1H NMR Acknowledgements
(500 MHz, CDCl3) δ 8.29 (dd, J = 10.2, 5.2 Hz, 2H), 8.21 (d, J =
This work was supported by the Shandong Provincial Natural
Science Foundation (ZR2017LB006).
8.6 Hz, 1H), 8.19–8.12 (m, 2H), 8.02 (dd, J = 9.0, 1.9 Hz, 1H),
7.85 (d, J = 9.0 Hz, 1H), 7.23 (t, J = 8.6 Hz, 2H). 13C NMR
(126 MHz, CDCl3) δ 166.06 (d, J = 257.0 Hz), 158.50, 146.32,
139.99, 137.59, 136.56, 134.68, 132.10 (d, J = 8.8 Hz), 131.66,
Notes and references
130.22, 118.27, 116.53 (d, J = 22.7 Hz), 95.82. HRMS (ESI)
calculated for C15H9FINO2S+: 413.9456 [M + H]+, found:
413.9451.
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