Regioselective Synthesis of Thieno[3,2-b]quinolones by Acylation/Two-Fold Buchwald–Hartwig Reactions

Article abstract of DOI:10.1002/ejoc.201901247

A variety of thienoquinolones were synthesized from readily accessible thiophene derivatives by regioselective acylations and subsequent two-fold Buchwald–Hartwig–amination. This cyclization allows a convenient synthesis of biologically and pharmaceutically important thienoquinolones. Several thienoquinolones were synthesized in good to very good yields. The optical properties of the products were studied in detail.

Full text of DOI:10.1002/ejoc.201901247

DOI: 10.1002/ejoc.201901247
Full Paper
Synthetic Methods
Regioselective Synthesis of Thieno[3,2-b]quinolones by
Acylation/Two-Fold Buchwald–Hartwig Reactions
Julia Janke,[a] Peter Ehlers,[a,b] Alexander Villinger,[a] and Peter Langer*[a,b]
Abstract: A variety of thienoquinolones were synthesized from and pharmaceutically important thienoquinolones. Several thi-
readily accessible thiophene derivatives by regioselective acyl-
ations and subsequent two-fold Buchwald–Hartwig–amination.
This cyclization allows a convenient synthesis of biologically
enoquinolones were synthesized in good to very good yields.
The optical properties of the products were studied in detail.
Introduction
thienoquinolones based on regioselective acylations and subse-
quent cyclizations by double C–N couplings forming a six-mem-
bered ring. This methodology is highly versatile and allows the
synthesis of various functionalized products in good to excel-
lent yields.
Quinolines annulated to other heterocycles have recently drawn
much attention, due to their considerable pharmacological and
biological activities.[1] In this context, thienoquinolines are of
considerable current interest as they possess anti-bacterial, anti-
inflammatory and anti-tumor properties.[2–4] Moreover, they are
immunoregulators,[3] drug resistance modulators,[3] memory en-
hancers[4,5] as well as analgesics[5] and antipyretics.[4,5] The quin-
olone substructure, contained in thienoquinolones, shows many
of the attributes of an ideal antibiotic, combining high potency,
a broad spectrum of activity, good bioavailability and a poten-
tially low incidence of side-effects.[6] Furthermore, acridones,
benzoannulated 4-quinolones, have attracted attention of both
medicinal and synthetic chemists, due to their biological activi-
ties.[7–11] Acridone derivatives have been reported to be signifi-
cant antifungal and antiviral agents[8,10,11,12] and can also be em-
ployed as chemosensors and fluorescent labels in biodiagnostics,
or find application as opto-electronic materials such as OLEDs.[12]
Due to the structural resemblance of quinolones and acridones
to thienoquinolones, it can be assumed that the latter also have
interesting biological or physical (optical) properties.
Results and Discussion
The starting material, (2-bromophenyl)(3-bromothiophen-2-yl)-
methanone 3a, was prepared by Friedel–Crafts-acylation of
commercially available 3-bromothiophene with 2-bromobenzo-
yl chloride in the presence of aluminum chloride (Scheme 1).
Scheme 1. Synthesis of 3a.
Subsequently, the palladium catalyzed Buchwald–Hartwig-
amination of 3a with p-toluidine was studied (Table 1). To our
delight, an initial test reaction using Pd2dba3 and dppf in tolu-
ene gave the desired product 4a in 45 % yield (Table 1, entry 1).
The use of different palladium catalysts could not increase the
yield of 4a (Table 1, entry 2–4). Next, we screened several phos-
phane ligands and solvents under otherwise identical condi-
tions (Table 1, entries 5–11). The bidentate phosphane ligands
BINAP and dppf gave an improved yield of 40 % (Table 1, en-
tries 5 and 10). All other ligands resulted in significantly lower
yields. Surprisingly, potassium tert-butoxide proved to be more
efficient than sodium tert-butoxide and led to a significantly
increased yield of 76 % (Table 1, entry 12).
Several intramolecular synthetic methodologies have been
developed to obtain the acridone scaffold in the past.[13] In
particular, we recently reported the synthesis of acridones by a
ring-closing two-fold Buchwald–Hartwig reaction of 2,2′-di-
bromobenzophenones.[14] This strategy has been frequently
used for the construction of 5-membered rings,[15] but has only
scarcely been employed for the construction of larger N-hetero-
cycles.[16] In the present study, we report what is, to the best of
our knowledge, a new and convenient synthesis of substituted
[a] Institute of Chemistry, University Rostock,
Albert-Einstein-Str. 3a, 18059 Rostock, Germany
[b] Leibniz-Institut für Katalyse e.V. an der Universität Rostock,
A.-Einstein-Str. 29a, 18059 Rostock, Germany
With the optimized conditions in hand, the Buchwald–
Hartwig reaction with various amines was studied (Table 2). The
yields vary from moderate to excellent. With regard to the sub-
stitution pattern of the employed anilines, electron-withdraw-
ing and electron-donating groups both proved to be compati-
E-mail: peter.langer@uni-rostock.de
https://www.langer.chemie.uni-rostock.de/
Supporting information and ORCID(s) from the author(s) for this article are
available on the WWW under https://doi.org/10.1002/ejoc.201901247.
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Table 1. Optimization for the Buchwald–Hartwig-amination of 4a.[a]
Entry
Catalyst
Ligand
Base
Solvent
Temperature
[°C]
Yield[b]
[%]
1
2
3
4
5
6
7
8
Pd2dba3
Pd(dba)2
Pd(PPh3)4
Pd(PPh3)4
Pd2dba3
Pd2dba3
Pd2dba3
Pd2dba3
Pd2dba3
Pd2dba3
Pd2dba3
Pd2dba3
Dppf
Dppf
–
NaOtBu
NaOtBu
NaOtBu
NaOtBu
NaOtBu
NaOtBu
NaOtBu
NaOtBu
NaOtBu
NaOtBu
NaOtBu
KOtBu
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Xylene
100
100
100
100
100
100
100
100
100
140
90
45
16
4
Dppf
13
40
10
26
22
24
40
22
76
BINAP
Xantphos
RuPhos
PtBu3·HBF4
XPhos
Dppf
9
10
11
12
Dppf
Dppf
1,4-dioxane
Toluene
100
[a] Reaction conditions: 3a (1.0 equiv., 0.3 mmol), Pd2dba3 (0.05 equiv., 0.015 mmol), p-toluidine (3.0 equiv., 0.9 mmol) and ligand (monodentate PtBu3·HBF4,
RuPhos or XPhos 0.2 equiv.; bidentate BINAP, Xantphos or dppf 0.1 equiv.), base (6.0 equiv., 1.8 mmol), 3.0 mL of solvent, 24 h. [b] Isolated yields.
Table 2. Synthesis of 4a–p.[a,b]
ble with the developed reaction conditions and gave equally
good results. The highest yield was observed for 4b (91 %),
while 4h, containing a CF3-group attached in ortho-position of
the aniline, could be isolated in only 32 % yield. Thus, steric
congestion has a high impact on the reaction outcome. On the
other hand, the electronic nature of the aniline does not appear
to have a clear influence on the yield. The reaction condition
could be successfully applied to the use of various benzylic
and aliphatic amines. These reactions gave rise to formation of
thienoquinolones 4k–p in slightly lower yields as compared to
the aniline derived derivatives (up to 57 %).
The molecular structures of 4c and 4o were independently
confirmed by X-ray crystal structure analysis (Figure 1 and Fig-
[a] Reaction conditions: 3a (1.0 equiv.), Pd2dba3 (0.05 equiv.), amine
(3.0 equiv.); dppf (0.1 equiv.), KOtBu (6.0 equiv.), toluene, 100 °C, 24 h. [b]
Isolated yields are given in parenthesis.
Figure 1. ORTEP of 4c.
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ure 2).[17] 4-(4-tert-Butylphenyl)thieno[3,2-b]quinolin-9(4H)-one
(4c) forms layers in a monoclinic crystal lattice. The thienoquin-
olone core is planar with the 4-tert-butylphenyl group twisted
out of the aromatic plane by 79.4°. In contrast, 4-hexylthi-
eno[3,2-b]quinolin-9(4H)-one (4o) forms layers in an orthorhom-
bic crystal lattice.
Figure 3. Starting materials 1b,c and 2b,c.
Substituted (2-bromophenyl)(3-bromothiophen-2-yl)meth-
anones 3b–e were prepared according to the same conditions
as reported for the synthesis of 3a. The yields vary from being
moderate (3e, 59 %) to very good (3b, 80 %) (Figure 4).
Figure 4. Substituted (2-bromophenyl)(3-bromothiophen-2-yl)methanones
3b–e.
The subsequent Buchwald–Hartwig reaction of 3b-3e with
tert-butylaniline and starting materials gave equally good yields
in a range from 55–69 % yield (Scheme 2).
Figure 2. ORTEP of 4o.
Optical Properties
Next, we turned our attention to the employment of substi-
tuted (2-bromophenyl)(3-bromothiophen-2-yl)methanone de- Selected compounds (4c, 4d, 4f, 4i and 4o) were investigated
rivatives. Exemplarily, we chose substituted thiophenes (1b and by UV/Vis and fluorescence spectroscopy in dichloromethane.
1c) as well as acid chlorides containing either a methoxy group The optical properties of these compounds are summarized in
(2b) or a fluorine moiety (2c) (Figure 3).
Table 3 and depicted in Figure 5.
Scheme 2. A: Synthesis of 4q,r; B: synthesis of 4s,t.
Table 3. Optical data of selected thienoquinolones.
λ
abs1[nm] (ε1)[a]
λ
abs2 [nm] (ε2)[a]
λ
abs3 [nm] (ε3)[a]
λem1 [nm]
λem2 [nm]
φ [%][b]
4d
4c
4i
4f
4o
254[b] (2.9)
253[b] (2.9)
254[b] (3.9)
252[b] (2.9)
258b (4.1)
350 (1.4)
351 (1.3)
351 (1.8)
349 (1.3)
355 (1.6)
367 (2.0)
368 (2.0)
367 (2.6)
365 (2.0)
373 (2.4)
374
376
380
373
378
391
392
389
390
397
6
8
3
5
11
[a] [10–4 L mol–1 cm–1]. [b] Using quinine sulfate in 0.05
M
H2SO4 fluorescence standard (φ = 0.51).[18]
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Table 4. Solvatochromic studies using 4o.
Solvent
λ
abs2 [nm] (ε2)[a]
λ
abs3 [nm] (ε3)[a]
λem1 [nm]
λem2 [nm]
φ [%][b]
Acetonitrile
Acetone
Toluene
353 (1.2)
353 (1.1)
353 (1.0)
350 (1.0)
371 (1.8)
370 (1.7)
371 (1.7)
368 (1.8)
377
375
377
371
395
394
395
390
83
49
21
1
Cyclohexane
[a] [10–4 L mol–1 cm–1]. [b] Using quinine sulfate in 0.05
M
H2SO4 fluorescence standard (φ = 0.51).[18]
Figure 6. Solvatochromic effects for compound 4o.
Figure 5. Normalized absorption- and emission spectra of selected com-
pounds in dichloromethane.
mic shifts of absorption- and emission bands accompanying
with high quantum yields (λmax = 403 nm; λem = 413, 435;
f = 68 %).[19]
All measured absorption and emission spectra of analyzed
compounds show similar band shapes and intensities. The ab-
sorption spectra consist of three absorption bands with a cer-
tain fine structure, while the emission spectra show a maximum
between 373–380 nm with a shoulder at lower energies. Aro-
matic substituents on the thienoquinolone nitrogen have only
marginal impact on the absorption and emission spectra, while
the presence of an aliphatic side chain leads to a slight red shift
of the absorption spectrum which might be due to an im-
proved donor ability of the alkyl chain as compared to the dis-
torted aryl rings (see Figure 1 and Figure 2). In case of 4i, the
shoulder at higher wavelengths of the emission spectrum is
more pronounced leading to a broader emission band. Quan-
tum yields are generally low in the measured solvent dichloro-
methane with the highest value of f = 11 % for 4o and the
lowest for 4i (f = 3 %).
Conclusion
In conclusion, we developed a new and convenient synthetic
pathway for the preparation of thienoquinolones via formation
of a six-membered ring by palladium catalyzed Buchwald–Hart-
wig aminations. Optimized reaction conditions allow modular
synthesis of various functionalized thienoquinolones tolerating
functional groups on the aromatic and heteroaromatic ring as
well as employment of anilines, benzylic- and aliphatic amines,
leading to corresponding products in good yields.
Experimental Section
Afterwards we analyzed the steady-state optical properties
of compound 4o in different solvents. While the shifts of ab-
sorption and emission bands shift only marginally (slightly
hypsochromic in cyclohexane), the optical quantum yield of
compound 4o depended strongly on the employed solvent
(Table 4 and Figure 6). In polar solvents, 4o exhibits high quan-
tum yields, with the best value measured in acetonitrile
(f = 83 %). In contrast, only low quantum yields are obtained in
nonpolar solvents with nearly no fluorescence in cyclohexane.
Comparing the UV/Vis data of 4o with corresponding n-hexyl
General. If not otherwise indicated, chemicals used in this study
were obtained from commercial sources. No further purifications
were done. Solvents, which were employed for work-up and purifi-
cation processes, were distilled according to standard procedures.
Silica gel (particle sizes 0.006 - 0.043 mm) were used for column
chromatography. Micro-Hot-Stage Galen TM III Cambridge Instru-
ment was used for melting point determination. The results were
not further corrected. NMR samples were measured with Bruker
AVANCE 250 II (built 2006), Bruker AVANCE 300 III (built 2007) and
AVANCE 500 (built 2001). NMR-peaks were calibrated using standard
1
peaks of chloroform (7.260 ppm for H and at 77.160 ppm for 13C).
acridone it becomes apparent that acridones show bathochro- For peak descriptions, following abbreviations were used: s (singlet),
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d (doublet), t (triplet), dd (double doublet), ddd (double double
doublet), pt (pseudo triplet), q (quartet), p (pentet), hept (heptet).
CH3). 13C NMR (75 MHz, [D]Chloroform): δ = 186.7 (CO), 149.9 (CAr),
140.7 (CAr), 134.8 (CAr), 133.0 (CHAr), 132.3 (CHHetar), 131.3 (CHAr),
128.5 (CHAr), 127.4 (CHAr), 119.5 (CAr), 117.0 (CAr), 16.0 (CH3).
IR measurement was performed with Bruker ALPHA-P spectrometer
IR (ATR, cm–1): ν = 1620 (m), 1587 (m), 1513 (m), 1426 (s), 1289 (m),
˜
using ATR sampling technique.
W (weak), m (medium) and
1252 (m), 1173 (m), 1118 (m), 1026 (m), 1018 (m), 822 (m), 746 (s),
730 (m), 601 (m). MS (EI, 70 eV): m/z (%) = 362 ([M]+, 34), 361 (8),
360 ([M]+, 66), 359 (5), 358 ([M]+, 32), 205 (100), 203 (97), 200 (15),
185 (19), 183 (19), 172 (5), 171 (15), 157 (17), 155 (17). HRMS (EI):
Calculated for C12H8O1Br2S1 [M]+ 357.86571 found 357.86506, calcu-
lated for C12H8O1Br181Br1S1 [M]+ 359.86367 found 359.86315, calcu-
lated for C12H8O181Br2S1 [M]+ 361.86162 found 361.86083.
s (strong) were used for peak description. GC/MS-measurements
were conducted with Finnigan MAT 95-XP device using HP-5 capil-
lary column with helium carrier gas and electron ionization (EI) scan
technique at 70 eV. For HRMS, Finnigan MAT 95 XP device was
employed. Only signals with deviation of less than 2 m Da were
accounted as correct. X-ray single crystal structure analysis was per-
formed on a Bruker-Nonius Apex X8 CCD-diffractometer.
(3-Bromo-4,5-dimethylthiophen-2-yl)(2-bromophenyl)meth-
anone 3c
General synthetic procedure for the synthesis of (2-bromo-
phenyl)(3-bromothiophen-2-yl)methanone derivatives 3a–e
Compound 3c was synthesized according to the general procedure
as yellow solid (141 mg, 72 %) with a melting point of 95 – 97 °C.
1H NMR (300 MHz, [D]Chloroform): δ = 7.63 – 7.58 (m, 1H, CHAr),
7.42 – 7.36 (m, 1H, CHAr), 7.36 – 7.33 (m, 1H, CHAr), 7.33 – 7.29 (m,
1H, CHAr), 2.45 (d, 5J = 0.6 Hz, 3H, CH3), 2.15 (d, 5J = 0.6 Hz, 3H,
CH3). 13C NMR (75 MHz, [D]Chloroform): δ = 186.6 (CO), 143.8 (CAr),
141.3 (CAr), 136.8 (CAr), 133.0 (CHAr), 132.8 (CAr), 131.1 (CHAr), 128.4
(CHAr), 127.3 (CHAr), 120.3 (CAr), 119.5 (CAr), 15.0 (CH3), 14.0 (CH3).
Aluminum chloride (0.6 mmol, 410 mg) was subjected to a Schlenk
flask under argon and solved in 6.0 mL of dried dichloromethane.
After 15 minutes stirring at 0 °C, 2-bromobenzoyl chloride deriva-
tives 2a–c (1.2 mmol, 0.8 mL) were added and the reaction mixture
was stirred for further 15 minutes at 0 °C. Subsequently, 3-bromo-
thiophene derivatives 1a–c (0.6 mmol, 0.3 mL) were added and the
flask was sealed with a septum before being stirred at 25 °C for 5 h.
The residue was diluted with dichloromethane (20.0 mL), washed
with water and dried with Na2SO4 and filtered afterwards. After
evaporation of the solvent, the crude solid was purified by column
chromatography (heptane/ethyl acetate, 10:1).
IR (ATR, cm–1): ν = 2921 (w), 2852 (w), 1620 (m), 1588 (m), 1423 (s),
˜
1293 (m), 1252 (m), 1138 (m), 1024 (m), 1006 (m), 743 (s), 724 (m),
632 (m). MS (EI, 70 eV): m/z (%) = 376 ([M]+, 44), 375 (15), 374 ([M]+,
63), 373 (15), 372 ([M]+, 30), 219 (85), 217 (100), 214 (18), 185 (40),
183 (35), 157 (44), 155 (50). HRMS (EI): Calculated for C13H10O1Br2S1
[M]+ 371.88136 found 371.88097, calculated for C13H10O1Br181Br1S1
[M]+ 373.87932 found 373.87904, calculated for C13H10O181Br2S1
[M]+ 375.87727 found 375.87710.
General synthetic procedure for the synthesis of thienoquinol-
ones 4a–t
(2-Bromophenyl)(3-bromothiophen-2-yl)methanone derivatives 3a–
e (0.3 mmol, 100 mg), Pd2dba3 (0.015 mmol, 14 mg), dppf
(0.03 mmol, 16 mg), KOtBu (1.8 mmol, 200 mg) and the respective
amine (0.9 mmol, 0.1 mL) were subjected to a dried glass pressure
tube under argon. The solids were solved in 3.0 mL of dried toluene,
sealed with a Teflon cap before being heated to 100 °C. After 24 h,
it was cooled to room temperature. The residue was dissolved in
(2-Bromo-5-methoxyphenyl)(3-bromothiophen-2-yl)meth-
anone 3d
Compound 3d was synthesized according to the general procedure
as yellow solid (154 mg, 67 %) with a melting point of 85 – 87 °C.
1H NMR (300 MHz, [D]Chloroform): δ = 7.61 (d, 3J = 5.2 Hz, 1H,
CH2Cl2 (20.0 mL), washed with hydrochloric acid (1 M, 20.0 mL) and
3
CHHetar), 7.47 – 7.39 (m, 1H, CHAr), 7.07 (d, J = 5.2 Hz, 1H, CHHetar),
dried with Na2SO4, and filtered afterwards. After evaporation of the
solvent, the crude solid was purified by column chromatography
(heptane/ethyl acetate, 10:1).
6.89 – 6.84 (m, 2H, CHAr), 3.75 (s, 3H, OCH3). 13C NMR (75 MHz,
[D]Chloroform): δ = 186.7 (CO), 158.9 (CAr), 141.0 (CAr), 136.7 (CAr),
134.3 (CHHetar), 133.9 (CHHetar), 133.8 (CHAr), 117.8 (CHAr), 117.1 (CAr),
(2-Bromophenyl)(3-bromothiophen-2-yl)methanone 3a
113.9 (CHAr), 109.7 (CAr), 55.7 (OCH3). IR (ATR, cm–1): ν = 3101 (w),
˜
2933 (w), 1652 (m), 1566 (m), 1462 (m), 1393 (s), 1352 (m), 1289
(m), 1236 (m), 1217 (m), 1119 (m), 1050 (m), 1015 (m), 875 (m), 790
(s), 590 (m). MS (EI, 70 eV): m/z (%) = 378 ([M]+, 20), 376 ([M]+, 42),
374 ([M]+, 18), 216 (64), 191 (100), 189 (98), 172 (34), 170 (33), 145
(28), 82 (66). HRMS (EI): Calculated for C12H8O2Br2S1 [M]+ 373.86063
found 373.86033, calculated for C12H8O2Br181Br1S1 [M]+ 375.85858
found 375.85845, calculated for C12H8O281Br2S1 [M]+ 377.85653
found 377.85636.
Compound 3a was synthesized according to the general procedure
as yellow solid (159 mg, 75 %), with a melting point of 103 – 105 °C.
1H NMR (300 MHz, [D]Chloroform): δ = 7.66 – 7.60 (m, 2H, CHAr),
3
7.46 – 7.31 (m, 3H, CHAr), 7.12 (d, J = 5.2 Hz, 1H, CHHetar). 13C NMR
(75 MHz, [D]Chloroform): δ = 187.3 (CO), 140.6 (CAr), 137.2 (CAr),
134.0 (CHHetar), 133.8 (CHHetar), 133.2 (CHAr), 131.7 (CHAr), 128.8
(CHAr), 127.6 (CHAr), 119.7 (CAr), 117.1 (CAr). IR (ATR, cm–1): ν = 3101
˜
(w), 3087 (w), 1650 (m), 1483 (m), 1429 (m), 1394 (s), 1355 (m), 1265
(m), 1133 (m), 1027 (m), 937 (m), 927 (m), 877 (s), 808 (m), 765 (m),
757 (s), 738 (s). MS (EI, 70 eV): m/z (%) = 348 ([M]+, 40), 347 (10),
346 ([M]+, 74), 344 ([M]+, 37), 191 (100), 189 (99), 186 (23), 185
(39), 183 (41), 158 (18), 157 (28), 155 (26). HRMS (EI): Calculated
for C11H6O1Br2S1 [M]+ 343.85006 found 343.84993, calculated for
C11H6O1Br181Br1S1 [M]+ 345.84802 found 345.84798, calculated for
C11H6O181Br2S1 [M]+ 347.84597 found 347.84600.
(2-Bromo-4-fluorophenyl)(3-bromothiophen-2-yl)methanone
3e
Compound 3e was synthesized according to the general procedure
as yellow solid (132 mg, 59 %) with a melting point of 92 – 94 °C.
1H NMR (300 MHz, [D]Chloroform): δ = 7.64 (d, 3J = 5.2 Hz, 1H,
CHHetar), 7.42 – 7.33 (m, 2H, CHAr), 7.18 – 7.08 (m, 2H, CHAr). 19F NMR
(282 MHz, [D]Chloroform): δ = –107.1. 13C NMR (75 MHz, [D]Chloro-
(3-Bromo-5-methylthiophen-2-yl)(2-bromophenyl)methanone
3b
1
form): δ = 186.0 (CO), 162.9 (d, JCF = 255.1 Hz, CF), 136.7 (CAr),
4
136.3 (d, JCF = 3.7 Hz, CAr), 133.8 (CHHetar), 133.4 (CHHetar), 130.0
3
2
Compound 3b was synthesized according to the general procedure (d, JCF = 9.1 Hz, CHAr), 120.3 (d, JCF = 24.6 Hz, CHAr), 120.3
3
2
as yellow solid (162 mg, 80 %) with a melting point of 84 – 86 °C.
(d, JCF = 9.9 Hz, CAr), 116.7 (CAr), 114.6 (d, JCF = 21.6 Hz, CHAr).
1H NMR (300 MHz, [D]Chloroform): δ = 7.63 – 7.59 (m, 1H, CHAr), IR (ATR, cm–1): ν = 3100 (w), 3087 (m), 1650 (m), 1483 (m), 1428 (m),
˜
7.44 – 7.38 (m, 1H, CHAr), 7.36 – 7.35 (m, 1H, CHAr), 7.34 – 7.30 (m,
1394 (s), 1355 (m), 1264 (m), 1234 (m), 1133 (m), 1080 (m), 1026
4
4
1H, CHAr), 6.83 (q, J = 1.0 Hz, 1H, CHHetar), 2.52 (d, J = 1.0 Hz, 3H,
(m), 928 (m), 877 (m), 756 (s), 628 (m). MS (EI, 70 eV): m/z (%) = 366
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3
4
5
([M]+, 53), 364 ([M]+, 100), 362 ([M]+, 48), 203 (58), 201 (58), 191 [D]Chloroform): δ = 8.59 (ddd, J = 8.0 Hz, J = 1.7 Hz, J = 0.5 Hz,
(95), 189 (91), 175 (28), 173 (27), 94 (41). HRMS (EI): Calculated for
1H, CHAr), 7.73 – 7.65 (m, 3H, CHAr), 7.64 (d, 3J = 5.5 Hz, 1H, CHHetar),
C11H5O1Br2F1S1 [M]+ 361.84064 found 361.84064, calculated for 7.52 (ddd, 3J = 8.6 Hz,3J = 7.0 Hz, J = 1.7 Hz, 1H, CHAr), 7.45 – 7.40
4
C11H5O1Br181Br1F1S1 [M]+ 363.83859 found 363.83787, calculated for
C11H5O181Br2F1S1 [M]+ 365.83655 found 365.83590.
(m, 2H, CHAr), 7.35 (ddd, 3J = 8.1 Hz, 3J = 7.0 Hz, 4J = 1.1 Hz, 1H,
CHAr), 6.94 (ddd, 3J = 8.6 Hz, 4J = 1.0 Hz, 5J = 0.5 Hz, 1H, CHAr), 6.50
(d, J = 5.5 Hz, 1H, CHHetar). 13C NMR (75 MHz, [D]Chloroform): δ =
3
4-p-Tolylthieno[3,2-b]quinolin-9(4H)-one 4a
173.6 (CO), 148.2 (CAr), 142.6 (CAr), 140.0 (CAr), 134.3 (CHHetar), 132.6
(CHAr), 131.3 (2CHAr), 130.3 (CHAr), 129.5 (2CHAr), 127.1 (CHAr), 123.0
(CAr), 123.0 (CHAr), 122.3 (CAr), 118.8 (CHHetar), 117.0 (CHAr).
Compound 4a was synthesized according to the general procedure
as pale yellow solid (64 mg, 76 %) with a melting point of 278 -
280 °C. 1H NMR (250 MHz, [D]Chloroform): δ = 8.57 (dd, 3J = 8.2 Hz,
IR (ATR, cm–1): ν = 3050 (w), 2921 (w), 1619 (m), 1581 (s), 1527 (m),
˜
3
4J = 1.5 Hz, 1H, CHAr), 7.61 (d, J = 5.4 Hz, 1H, CHHetar), 7.54 – 7.41
1486 (m), 1463 (m), 1295 (m), 1155 (m), 1033 (m), 879 (m), 844 (m),
802 (m), 769 (m), 750 (s). MS (EI, 70 eV): m/z (%) = 279 (6), 278 (19),
277 ([M]+, 100), 276 (14), 249 (8), 248 (9), 247 (6), 204 (6), 138 (5),
128 (4), 77 (4), 51 (4). HRMS (EI): Calculated for C17H11O1N1S1 [M]+
277.05559 found 277.05557.
(m, 3H, CHAr), 7.37 – 7.24 (m, 3H, CHAr), 6.96 (d, 3J = 8.5 Hz, 1H,
CHAr), 6.52 (d, 3J = 5.4 Hz, 1H, CHHetar), 2.51 (s, 3H, CH3). 13C NMR
(63 MHz, [D]Chloroform): δ = 173.0 (CO), 148.0 (CAr), 142.3 (CAr),
140.0 (CAr), 136.9 (CAr), 133.8 (CHHetar), 132.1 (CHAr), 131.4 (2CHAr),
128.7 (2CHAr), 126.5 (CHAr), 122.5 (CAr), 122.4 (CHAr), 121.7 (CAr),
4-(4-Chlorophenyl)thieno[3,2-b]quinolin-9(4H)-one 4e
118.5 (CHHetar), 116.6 (CHAr), 21.4 (CH3). IR (ATR, cm–1): ν = 3112 (w),
˜
Compound 4e was synthesized according to the general procedure
as pale yellow solid (36 mg, 40 %) with a melting point of 266 –
268 °C. 1H NMR (250 MHz, [D]Chloroform): δ = 8.59 (dd, 3J = 8.1 Hz,
4J = 1.3 Hz, 1H, CHAr), 7.71 – 7.63 (m, 3H, CHAr), 7.60 – 7.50 (m, 1H,
CHAr), 7.44 – 7.33 (m, 3H, CHAr), 7.02 – 6.87 (m, 1H, CHAr), 6.52 (d,
3J = 5.2 Hz, 1H, CHHetar). 13C NMR (63 MHz, [D]Chloroform): δ =
172.8 (CO), 147.3 (CAr), 141.8 (CAr), 137.9 (CAr), 135.9 (CAr), 134.1
(CHHetar), 132.3 (CHAr), 131.1 (2CHAr), 130.5 (2CHAr), 126.6 (CHAr),
122.6 (CHAr), 122.3 (CAr), 121.8 (CAr), 117.9 (CHHetar), 116.1 (CHAr).
2921 (w), 1618 (m), 1591 (s), 1511 (m), 1488 (m), 1295 (m), 1261
(m), 1182 (m), 1168 (m), 1095 (m), 1031 (m), 879 (m), 823 (m), 808
(m), 754 (s). MS (EI, 70 eV): m/z (%) = 293 (6), 292 (19), 291 ([M]+,
100), 290 (11), 276 (4), 263 (5), 262 (5), 247 (4), 145 (8), 138 (5).
HRMS (EI): Calculated for C18H13O1N1S1 [M]+ 291.07124 found
291.07116.
4-(4-Ethylphenyl)thieno[3,2-b]quinolin-9(4H)-one 4b
Compound 4b was synthesized according to the general procedure
as pale yellow solid (80 mg, 91 %) with a melting point of 205 –
207 °C. 1H NMR (250 MHz, [D]Chloroform): δ = 8.69 (dd, 3J = 8.1 Hz,
IR (ATR, cm–1): ν = 2921 (w), 2852 (w), 1619 (m), 1587 (s), 1527 (m),
˜
1486 (m), 1444 (m), 1297 (m), 1166 (m), 1153 (m), 1089 (m), 1012
(m), 923 (m), 879 (m), 827 (m), 752 (s). MS (EI, 70 eV): m/z (%) = 313
(36), 312 (21), 311 ([M]+, 100), 283 (8), 247 (13), 172 (9), 138 (8),
128 (11), 102 (8), 76 (8), 75 (19), 50 (9). HRMS (EI): Calculated for
C17H10O1N1Cl1S1 [M]+ 311.01661 found 311.01643.
3
4J = 1.4 Hz, 1H, CHAr), 7.74 (d, J = 5.5 Hz, 1H, CHHetar), 7.61 (m, 3H,
3
CHAr), 7.49 – 7.37 (m, 3H, CHAr), 7.08 (d, J = 8.2 Hz, 1H, CHAr), 6.64
(d, 3J = 5.5 Hz, 1H, CHHetar), 2.93 (q, 3J = 7.6 Hz, 2H, CH2), 1.48 (t,
3J = 7.6 Hz, 3H, CH3). 13C NMR (63 MHz, [D]Chloroform): δ = 172.5
(CO), 147.5 (CAr), 145.7 (CAr), 141.8 (CAr), 136.5 (CAr), 133.3 (CHHetar),
131.6 (CHAr), 129.7 (2CHAr), 128.2 (2CHAr), 126.0 (CHAr), 121.9 (CAr),
121.9 (CHAr), 121.2 (CAr), 118.0 (CHHetar), 116.1 (CHAr), 28.2 (CH2),
4-(4-Fluorophenyl)thieno[3,2-b]quinolin-9(4H)-one 4f
Compound 4f was synthesized according to the general procedure
as pale yellow solid (62 mg, 73 %) with a melting point of 258 –
260 °C. 1H NMR (300 MHz, [D]Chloroform): δ = 8.59 (ddd, 3J =
14.9 (CH3). IR (ATR, cm–1): ν = 2972 (w), 2842 (w), 1619 (m), 1589
˜
(s), 1519 (m), 1490 (m), 1295 (m), 1168 (m), 1110 (m), 1049 (m), 923
(m), 871 (m), 829 (m), 750 (s). MS (EI, 70 eV): m/z (%) = 307 (6), 306
(21), 305 ([M]+, 100), 291 (6), 290 (29), 289 (7), 288 (5), 276 (8), 275
(4), 260 (5). HRMS (EI): Calculated for C19H15O1N1S1 [M]+ 305.08689
found 305.08667.
4
5
3
8.0 Hz, J = 1.7 Hz, J = 0.5 Hz, 1H, CHAr), 7.67 (d, J = 5.5 Hz, 1H,
CHHetar), 7.54 (ddd, 3J = 8.6 Hz, 3J = 7.0 Hz, J = 1.7 Hz, 1H, CHAr),
4
7.46 – 7.33 (m, 5H, CHAr), 6.91 (dd, 3J = 8.6 Hz, 5J = 0.5 Hz, 1H, CHAr),
6.50 (d, 3J = 5.5 Hz, 1H, CHHetar). 19F NMR (282 MHz, [D]Chloroform):
δ = –110.10. 13C NMR (75 MHz, [D]Chloroform): δ = 173.5 (CO), 163.5
(d, 1JCF = 251.0 Hz, CF), 148.2 (CAr), 142.7 (CAr), 136.0 (d, 4JCF = 3.6 Hz,
4-(4-tert-Butylphenyl)thieno[3,2-b]quinolin-9(4H)-one 4c
3
Compound 4c was synthesized according to the general procedure
as pale yellow solid (70 mg, 73 %) with a melting point of 200 –
202 °C. 1H NMR (300 MHz, [D]Chloroform): δ = 8.58 (ddd, 3J =
CAr), 134.5 (CHHetar), 132.8 (CHAr), 131.5 (d, JCF = 8.8 Hz, 2CHAr),
127.2 (CHAr), 123.1 (CHAr), 123.1 (CAr), 122.4 (CAr), 118.6 (CHHetar),
118.4 (d, 2JCF = 21.3 Hz, 2CHAr), 116.7 (CHAr). IR (ATR, cm–1): ν = 3050
˜
4
5
8.1 Hz, J = 1.7 Hz, J = 0.5 Hz, 1H, CHAr), 7.67 – 7.63 (m, 2H, CHAr),
(w), 2921 (w), 2852 (w), 1718 (w), 1621 (m), 1529 (s), 1508 (m), 1490
(m), 1297 (m), 1218 (m), 1157 (m), 1056 (m), 921 (m), 881 (m), 833
(m), 773 (m), 748 (s). MS (EI, 70 eV): m/z (%) = 297 (5), 296 (19), 295
([M]+, 100), 294 (10), 267 (10), 266 (8), 265 (5), 222 (6), 145 (8), 172
(4), 147 (4), 75 (4). HRMS (EI): Calculated for C17H10O1N1F1S1 [M]+
295.04616 found 295.04577.
3
3
3
7.61 (d, J = 5.5 Hz, 1H, CHHetar), 7.51 (ddd, J = 8.6 Hz, J = 7.0 Hz,
4J = 1.7 Hz, 1H, CHAr), 7.38 – 7.28 (m, 3H, CHAr), 6.99 – 6.94 (m, 1H,
CHAr), 6.53 (d, J = 5.5 Hz, 1H, CHHetarr), 1.44 (s, 9H, CH3). 13C NMR
3
(75 MHz, [D]Chloroform): δ = 173.1 (CO), 153.1 (CAr), 148.0 (CAr),
142.3 (CAr), 136.8 (CAr), 133.8 (CHHetar), 132.1 (CHAr), 128.4 (2CHAr),
127.7 (2CHAr), 126.5 (CHAr), 122.5 (CAr), 122.4 (CHAr), 121.7 (CAr),
118.6 (CHHetar), 116.7 (CHAr), 35.1 (CtBu), 31.5 (3CH3). IR (ATR, cm–1):
4-(3-Fluorophenyl)thieno[3,2-b]quinolin-9(4H)-one 4g
Compound 4g was synthesized according to the general procedure
as yellow solid (43 mg, 50 %) with a melting point of 260 – 262 °C.
1H NMR (250 MHz, [D]Chloroform): δ = 8.56 (dd, 3J = 8.1 Hz, 4J =
ν = 2960 (m), 2923 (m), 2865 (w), 1650 (m), 1618 (m), 1591 (s), 1488
˜
(m), 1446 (m), 1295 (m), 1247 (m), 1170 (m), 1116 (m), 1035 (m),
881 (m), 752 (s). MS (EI, 70 eV): m/z (%) = 335 (7), 334 (23), 333
([M]+, 100), 319 (15), 318 (66), 303 (5), 290 (11), 276 (5), 200 (6), 172
(7), 145 (18). HRMS (EI): Calculated for C21H19O1N1S1 [M]+ 333.11819
found 333.11809.
3
1.4 Hz, 1H, CHAr), 7.73 – 7.66 (m, 1H, CHAr), 7.66 (d, J = 5.3 Hz, 1H,
4
CHHetar), 7.53 (ddd, 3J = 8.6 Hz, 3J = 7.0 Hz, J = 1.6 Hz, 1H, CHAr),
7.42 – 7.23 (m, 3H, CHAr), 7.22 – 7.14 (m, 1H, CHAr), 6.93 (d, 3J =
8.5 Hz, 1H, CHAr), 6.52 (d, 3J = 5.4 Hz, 1H, CHHetar). 19F NMR
(282 MHz, [D]Chloroform): δ = –108.51. 13C NMR (63 MHz,
4-Phenylthieno[3,2-b]quinolin-9(4H)-one 4d
1
Compound 4d was synthesized according to the general procedure
[D]Chloroform): δ = 172.4 (CO), 163.2 (d, JCF = 251.3 Hz, CF), 146.8
1
3
as pale yellow solid (66 mg, 82 %) 290 – 292 °C. H NMR (300 MHz,
(CAr), 141.3 (CAr), 140.3 (d, JCF = 9.4 Hz, CAr), 133.8 (CHHetar), 131.9
Eur. J. Org. Chem. 2019, 7255–7263
www.eurjoc.org
7260
© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Full Paper
3
4
(CHAr), 131.7 (d, JCF = 9.0 Hz, CHAr), 126.1 (CHAr), 124.5 (d, JCF
=
(m), 1259 (m), 1203 (m), 1153 (m), 1057 (m), 1037 (m), 829 (m), 751
3.4 Hz, CHAr), 122.3 (CHAr), 121.9 (CAr), 121.4 (CAr), 117.5 (CHHetar), (s). MS (EI, 70 eV): m/z (%) = 339 (9), 338 (23), 337 ([M]+, 100), 336
116.8 (d, JCF = 20.8 Hz, CHAr), 116.3 (d, 2J = 22.4 Hz, CHAr), 115.7 (19), 321 (5), 250 (5), 69 (6), 63 (7), 51 (5). HRMS (EI): Calculated for
2
(CHAr). IR (ATR, cm–1): ν = 3052 (w), 1621 (m), 1592 (s), 1529 (m),
C19H15O3N1S1 [M]+ 337.07672 found 337.07643.
˜
1492 (m), 1465 (m), 1301 (m), 1224 (m), 1170 (m), 1078 (m), 962
(m), 881 (m), 835 (m), 796 (m), 746 (s). MS (EI, 70 eV): m/z (%) = 297
(6), 296 (19), 295 ([M]+, 100), 294 (12), 267 (9), 266 (7), 265 (4), 222
(5), 172 (4), 147 (4), 75 (4). HRMS (EI): Calculated for C17H10O1N1F1S1
[M]+ 295.04616 found 295.04664.
4-Benzylthieno[3,2-b]quinolin-9(4H)-one 4k
Compound 4k was synthesized according to the general procedure
as pale yellow solid (58 mg, 57 %) with a melting point of 157 –
159 °C. 1H NMR (250 MHz, [D]Chloroform): δ = 8.54 (dd, 3J = 8.0 Hz,
4J = 1.6 Hz, 1H, CHAr), 7.69 (d, 3J = 5.5 Hz, 1H, CHHetar), 7.54 (ddd,
4-(2-(Trifluoromethyl)phenyl)thieno[3,2-b]quinolin-9(4H)-one
3
4
3J = 8.6 Hz, J = 6.9 Hz, J = 1.6 Hz, 1H, CHAr), 7.40 – 7.22 (m, 5H,
CHAr), 7.11 – 7.08 (m, 2H, CHAr), 7.06 (d, 3J = 5.5 Hz, 1H, CHHetar),
5.55 (s, 2H, CH2). 13C NMR (63 MHz, [D]Chloroform): δ = 173.3 (CO),
147.9 (CAr), 141.4 (CAr), 135.8 (CAr), 135.2 (CHHetar), 133.2 (CHAr), 129.7
(2CHAr), 128.5 (CHAr), 127.4 (CHAr), 126.2 (2CHAr), 123.5 (CAr), 122.9
(CAr), 122.8 (CHAr), 117.6 (CHHetar), 115.5 (CHAr), 52.5 (CH2).
4h
Compound 4h was synthesized according to the general procedure
as yellow solid (32 mg, 32 %) with a melting point of 228 – 230 °C.
1H NMR (300 MHz, [D]Chloroform): δ = 8.58 (dd, 3J = 8.1 Hz, 4J =
1.5 Hz, 1H, CHAr), 8.01 (dd, 3J = 7.7 Hz, J = 1.1 Hz, 1H, CHAr), 7.93 –
4
7.76 (m, 2H, CHAr), 7.65 (d, 3J = 5.5 Hz, 1H, CHHetar), 7.57 – 7.45 (m,
IR (ATR, cm–1): ν = 3101 (w), 2921 (w), 1612 (m), 1573 (s), 1527 (m),
˜
3
3
4
2H, CHAr), 7.36 (ddd, J = 8.0 Hz, J = 7.1 Hz, J = 1.0 Hz, 1H, CHAr),
6.69 (d, 3J = 8.6 Hz, 1H, CHAr), 6.34 (d, 3J = 5.4 Hz, 1H, CHHetar).
19F NMR (282 MHz, [D]Chloroform): δ = –61.13. 13C NMR (75 MHz,
[D]Chloroform): δ = 173.6 (CO), 148.1 (CAr), 142.7 (CAr), 137.6 (d,
3JCF = 1.8 Hz, CAr), 135.2 (CHHetar), 134.7 (CHAr), 132.8 (CHAr), 132.4
1498 (m), 1454 (m), 1270 (m), 1174 (m), 747 (m), 1103 (m), 1076
(m), 966 (m), 883 (m), 823 (m), 756 (s). MS (EI, 70 eV): m/z (%) = 292
(7), 291 ([M]+, 39), 172 (4), 128 (4), 92 (7), 91 (100), 65 (9). HRMS (EI):
Calculated for C18H13O1N1S1 [M]+ 291.07124 found 291.07200.
4-(4-Methylbenzyl)thieno[3,2-b]quinolin-9(4H)-one 4l
2
3
(CHAr), 131.2 (CHAr), 130.3 (q, JCF = 31.8 Hz, C-CF3), 129.0 (q, JCF
4.9 Hz, CHAr), 127.0 (CHAr), 123.3 (CHAr), 123.0 (q, JCF = 274.2 Hz,
=
1
Compound 4l was synthesized according to the general procedure
as pale yellow solid (47 mg, 53 %) with a melting point of 256 –
258 °C. 1H NMR (250 MHz, [D]Chloroform): δ = 8.60 (dd, 3J = 8.1 Hz,
4J = 1.5 Hz, 1H, CHAr), 7.77 (d, 3J = 5.5 Hz, 1H, CHHetar), 7.61 (ddd,
CF3). 122.8 (CAr), 122.4 (CAr), 118.5 (CHHetar), 117.0 (CHAr).
IR (ATR, cm–1): ν = 3058 (w), 3037 (w), 1621 (m), 1592 (s), 1527 (m),
˜
1488 (m), 1450 (m), 1313 (m), 1268 (m), 1153 (m), 1108 (m), 1064
(m), 1035 (m), 879 (m), 846 (m), 756 (s). MS (EI, 70 eV): m/z (%) =
347 (6), 346 (20), 345 ([M]+, 100), 317 (11), 276 (9), 247 (4), 172 (7),
128 (4). HRMS (EI): Calculated for C18H10O1N1F3S1 [M]+ 345.04297
found 345.04311.
3
4
3
3J = 8.6 Hz, J = 6.9 Hz, J = 1.7 Hz, 1H, CHAr), 7.44 (d, J = 8.6 Hz,
3
3
4
1H, CHAr), 7.35 (ddd, J = 7.9 Hz, J = 6.9 Hz, J = 0.9 Hz, 1H, CHAr),
7.13 (d, 3J = 5.6 Hz, 1H, CHHetar), 7.12 (d, 3J = 7.7 Hz, 2H, CHAr), 7.02
(d, 3J = 8.1 Hz, 2H, CHAr), 5.58 (s, 2H, CH2), 2.31 (s, 3H, CH3). 13C NMR
(63 MHz, [D]Chloroform): δ = 172.9 (CO), 147.6 (CAr), 141.1 (CAr),
137.9 (CAr), 134.9 (CHHetar), 132.8 (CHAr), 132.2 (CAr), 130.0 (2CHAr),
127.1 (CHAr), 125.7 (2CHAr), 123.1 (CAr), 122.5 (CAr), 122.5 (CHAr),
117.1 (CHHetar), 115.0 (CHAr), 52.0 (CH2), 21.2 (CH3). IR (ATR, cm–1):
4-(4-Methoxyphenyl)thieno[3,2-b]quinolin-9(4H)-one 4i
Compound 4i was synthesized according to the general procedure
as pale yellow solid (49 mg, 55 %) with a melting point of 245 –
247 °C. 1H NMR (300 MHz, [D]Chloroform): δ = 8.56 (dd, 3J = 8.1 Hz,
4J = 1.3 Hz, 1H, CHAr), 7.63 (d, 3J = 5.5 Hz, 1H, CHHetar), 7.51 (ddd,
ν = 2921 (w), 2819 (w), 1618 (m), 1587 (m), 1494 (s), 1265 (m), 1170
˜
(m), 1076 (m), 950 (m), 881 (m), 833 (m), 750 (s). MS (EI, 70 eV):
m/z (%) = 306 (4), 305 ([M]+, 25), 172 (4), 106 (8), 105 (100), 103 (6),
79 (8), 77 (10). HRMS (EI): Calculated for C19H15O1N1S1 [M]+
305.08689 found 305.08687.
3J = 8.6 Hz, J = 7.0 Hz, J = 1.7 Hz, 1H, CHAr), 7.39 – 7.28 (m, 3H,
3
4
3
CHAr), 7.19 – 7.09 (m, 2H, CHAr), 6.97 (d, J = 8.6 Hz, 1H, CHAr), 6.53
(d, 3J = 5.5 Hz, 1H, CHHetar), 3.93 (s, 3H, OCH3). 13C NMR (75 MHz,
[D]Chloroform): δ = 172.6 (CO), 159.9 (CAr), 147.9 (CAr), 142.1 (CAr),
133.5 (CHHetar), 131.8 (CHAr), 131.6 (CAr), 129.6 (2CHAr), 126.1 (CHAr),
122.0 (CHAr), 122.0 (CAr), 121.2 (CAr), 118.1 (CHHetar), 116.2 (CHAr),
4-Cyclopentylthieno[3,2-b]quinolin-9(4H)-one 4m
Compound 4m was synthesized according to the general procedure
as yellow solid (28 mg, 36 %) with a melting point of 170 – 172 °C.
1H NMR (250 MHz, [D]Chloroform): δ = 8.63 – 8.57 (m, 1H, CHAr),
7.78 (d, 3J = 5.6 Hz, 1H, CHHetar), 7.68 – 7.64 (m, 2H, CHAr), 7.37 –
7.30 (m, 1H, CHAr), 7.29 (d, 3J = 5.6 Hz, 1H, CHHetar), 5.39 (p, 3J =
9.2 Hz, 1H, CH), 2.45 – 2.27 (m, 2H, CH2), 2.25 – 2.06 (m, 4H, CH2),
1.97 – 1.81 (m, 2H, CH2). 13C NMR (63 MHz, [D]Chloroform): δ =
172.9 (CO), 146.1 (CAr), 141.1 (CAr), 133.6 (CHHetar), 131.9 (CHAr), 127.4
(CHAr), 123.8 (CAr), 123.7 (CAr), 122.0 (CHAr), 118.0 (CHHetar), 115.8
115.5 (2CHAr), 55.3 (OCH3). IR (ATR, cm–1): ν = 3101 (w), 2958 (w),
˜
1618 (m), 1589 (s), 1506 (m), 1486 (m), 1442 (m), 1292 (m), 1241
(m), 1168 (m), 1151 (m), 1106 (m), 1049 (m), 1010 (m), 919 (m), 838
(m), 817 (m), 752 (s). MS (EI, 70 eV): m/z (%) = 309 (6), 308 (19), 307
([M]+, 100), 292 (24), 264 (6), 263 (9), 262 (6), 234 (5). HRMS (EI):
Calculated for C18H13O2N1S1 [M]+ 307.06615 found 307.06594.
4-(3,5-Dimethoxyphenyl)thieno[3,2-b]quinolin-9(4H)-one 4j
(CHAr), 60.9 (CH), 28.9 (CH2), 25.4 (CH2). IR (ATR, cm–1): ν = 2948 (m),
Compound 4j was synthesized according to the general procedure
as yellow solid (56 mg, 57 %) with a melting point of 261 – 264 °C.
1H NMR (500 MHz, [D]Chloroform): δ = 8.56 (dd, 3J = 8.1 Hz, 4J =
1.6 Hz, 1H, CHAr), 7.64 (d, 3J = 5.4 Hz, 1H, CHHetar), 7.53 (ddd, 3J =
8.6 Hz, 3J = 6.9 Hz, 4J = 1.7 Hz, 1H, CHAr), 7.34 (ddd, 3J = 7.9 Hz,
˜
2867 (m), 1614 (m), 1589 (s), 1521 (m), 1494 (m), 1388 (m), 1251
(m), 1187 (m), 1172 (m), 1078 (m), 1045 (m), 952 (m), 889 (m), 840
(m), 752 (s). MS (EI, 70 eV): m/z (%) = 270 (5), 269 ([M]+, 33), 203 (5),
202 (13), 201 (100), 173 (9), 172 (9), 128 (5), 69 (4), 41 (8). HRMS (EI):
Calculated for C16H15O1N1S1 [M]+ 269.08689 found 269.08651.
3J = 6.9, J = 1.0 Hz, 1H, CHAr), 7.06 (d, J = 8.6 Hz, 1H, CHAr), 6.68
(t, 4J = 2.3 Hz, 1H, CHAr), 6.63 (d, 3J = 5.4 Hz, 1H, CHHetar), 6.56
(d, 4J = 2.2 Hz, 2H, CHAr), 3.83 (s, 6H, OCH3). 13C NMR (126 MHz,
[D]Chloroform): δ = 173.0 (CO), 162.3 (2CAr), 147.4 (CAr), 141.8 (CAr),
4
3
4-Allylthieno[3,2-b]quinolin-9(4H)-one 4n
Compound 4n was synthesized according to the general procedure
141.0 (CAr), 133.7 (CHHetar), 132.1 (CHAr), 126.4 (CHAr), 122.4 (CHAr), as yellow solid (38 mg, 54 %) with a melting point of 112 – 114 °C.
122.3 (CAr), 121.6 (CAr), 118.4 (CHHetar), 116.6 (CHAr), 106.8 (2CHAr),
1H NMR (250 MHz, [D]Chloroform): δ = 8.56 (dd, 3J = 8.1 Hz, 4J =
101.8 (CHAr), 55.7 (2OCH3). IR (ATR, cm–1): ν = 2920 (m), 2851 (w), 1.5 Hz, 1H, CHAr), 7.76 (d, 3J = 5.5 Hz, 1H, CHHetar), 7.65 (ddd, 3J =
˜
3
4
1620 (m), 1590 (s), 1527 (m), 1491 (m), 1463 (m), 1425 (m), 1358 8.7 Hz, J = 6.9 Hz, J = 1.7 Hz, 1H, CHAr), 7.50 – 7.39 (m, 1H, CHAr),
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4
7.33 (ddd, 3J = 7.9 Hz, 3J = 7.0 Hz, J = 0.9 Hz, 1H, CHAr), 7.10 (d, 116.6 (CHAr), 35.1 (CtBu), 31.5 (3CH3), 17.0 (CH3). IR (ATR, cm–1): ν =
˜
3J = 5.5 Hz, 1H, CHHetar), 6.11 – 5.94 (m, 1H, CH), 5.30 – 4.99 (m, 2H,
2960 (w), 2868 (w), 1624 (m), 1592 (s), 1487 (m), 1446 (m), 1297 (m),
1264 (m), 1168 (m), 1154 (m), 1030 (m), 802 (m), 746 (s).
2CHC=C), 4.99 – 4.95 (m, 2H, CH2). 13C NMR (63 MHz, [D]Chloroform):
δ = 172.4 (CO), 146.6 (CAr), 140.2 (CAr), 134.2 (CHHetar), 132.2 (CHAr), MS (EI, 70 eV): m/z (%) = 349 (7), 348 (24), 347 ([M]+, 100), 333 (12),
130.0 (CH), 126.5 (CHAr), 122.4 (CAr), 121.9 (CAr), 121.8 (CHAr), 117.4 332 (54), 317 (8), 304 (6), 186 (4), 152 (10). HRMS (EI): Calculated for
(CH2=CH), 116.4 (CHHetar), 114.3 (CHAr), 50.1 (CH2). IR (ATR, cm–1):
C
22H21O1N1S1 [M]+ 347.13384 found 347.13348.
ν = 1704 (m), 1618 (m), 1583 (s), 1527 (m), 1500 (m), 1469 (m), 1359
˜
4-(4-tert-Butylphenyl)-2,3-dimethylthieno[3,2-b]quinolin-9(4H)-
one 4r
(m), 1267 (m), 1222 (m), 1174 (m), 1091 (m), 1043 (m), 883 (m), 835
(m), 758 (s). MS (EI, 70 eV): m/z (%) = 243 (5), 242 (16), 241 ([M]+,
100), 240 (20), 226 (9), 201 (14), 200 (97), 173 (6), 172 (48), 146 (9),
128 (21). HRMS (EI): Calculated for C14H11O1N1S1 [M]+ 241.05559
found 241.05491.
Compound 4r was synthesized according to the general procedure
as yellow solid (56 mg, 58 %) with a melting point of 325 – 327 °C.
1H NMR (250 MHz, [D]Chloroform): δ = 8.51 (dd, 3J = 8.1 Hz, 4J =
3
1.5 Hz, 1H, CHAr), 7.64 – 7.56 (m, 2H, CHAr), 7.44 (ddd, J = 8.7 Hz,
4-n-Hexylthieno[3,2-b]quinolin-9(4H)-one 4o
3J = 7.0 Hz, 4J = 1.7 Hz, 1H, CHAr), 7.36 – 7.27 (m, 3H, CHAr), 6.85 (d,
3J = 8.3 Hz, 1H, CHAr), 2.36 (s, 3H, CH3), 1.43 (s, 9H, CH3), 1.35 (s, 3H,
CH3). 13C NMR (63 MHz, [D]Chloroform): δ = 172.3 (CO), 153.5 (CAr),
145.7 (CAr), 144.4 (CAr), 143.2 (CAr), 136.6 (CAr), 131.6 (CHAr), 130.0
(2CHAr), 126.9 (2CHAr), 126.0 (CHAr), 124.0 (CAr), 122.2 (CHAr), 121.8
(CAr), 120.5 (CAr), 117.1 (CHAr), 35.0 (CtBu), 31.5 (3CH3), 15.7 (CH3),
Compound 4o was synthesized according to the general procedure
as pale yellow solid (44 mg, 53 %) with a melting point of 105 –
1
3
107 °C H NMR (300 MHz, [D]Chloroform): δ = 8.54 (d, J = 7.4 Hz,
1H, CHAr), 7.76 (d, J = 5.1 Hz, 1H, CHHetar), 7.66 (pt,3J = 7.4 Hz, 1H,
3
CHAr), 7.47 (d, 3J = 8.6 Hz, 1H, CHAr), 7.31 (pt, 3J = 7.4 Hz, 1H, CHAr),
7.15 (d, 3J = 5.2 Hz, 1H, CHHetar), 4.38 – 4.19 (m, 2H, CH2), 1.97 –
13.2 (CH3). IR (ATR, cm–1): ν = 2958 (w), 2922 (w), 2852 (w), 1618
˜
3
1.72 (m, 2H, CH2), 1.59 – 1.13 (m, 6H, CH2), 0.88 (t, J = 6.7 Hz, 3H,
(m), 1590 (s), 1476 (m), 1428 (m), 1294 (m), 1266 (m), 1166 (m), 1097
(m), 1029 (m), 895 (m), 745 (s). MS (EI, 70 eV): m/z (%) = 363 (9),
362 (27), 361 ([M]+, 100), 347 (15), 346 (73), 228 (8), 167 (10), 159
(13), 115 (10), 91 (12), 89 (14). HRMS (EI): Calculated for
CH3). 13C NMR (75 MHz, [D]Chloroform): δ = 173.0 (CO), 147.3 (CAr),
140.8 (CAr), 134.9 (CHHetar), 132.9 (CHAr), 127.5 (CHAr), 123.4 (CAr),
122.7 (CAr), 122.4 (CHAr), 117.2 (CHHetar), 114.8 (CHAr), 49.0 (CH2),
31.9 (CH2), 28.5 (CH2), 27.0 (CH2), 23.0 (CH2), 14.4 (CH3). IR C23H23O1N1S1 [M]+ 361.14949 found 361.14953.
(ATR, cm–1): ν = 2919 (m), 2858 (m), 1619 (m), 1587 (s), 1529 (m),
˜
4-(4-tert-Butylphenyl)-6-fluorothieno[3,2-b]quinolin-9(4H)-one
4s
1494 (m), 1467 (m), 1375 (m), 1270 (m), 1168 (m), 1079 (m), 1041
(m), 962 (m), 879 (m), 823 (m), 750 (s). MS (EI, 70 eV): m/z (%) = 285
([M]+, 43), 215 (15), 214 (100), 201 (12), 186 (15), 172 (6), 128 (5), 115
(5). HRMS (EI): Calculated for C17H19O1N1S1 [M]+ 285.11819 found
285.11827.
Compound 4t was synthesized according to the general procedure
as pale yellow solid (53 mg, 55 %) with a melting point of 275 –
277 °C. 1H NMR (300 MHz, [D]Chloroform): δ = 8.53 (dd, 3J = 9.0 Hz,
3J = 6.5 Hz, 1H, CHAr), 7.70 – 7.63 (m, 2H, CHAr), 7.59 (d, 3J = 5.4 Hz,
1H, CHHetar), 7.36 – 7.28 (m, 2H, CHAr), 7.01 (ddd, 3J = 9.0 Hz, 3J =
4-nButylthieno[3,2-b]quinolin-9(4H)-one 4p
4
3
4
Compound 4p was synthesized according to the general procedure 7.9 Hz, J = 2.4 Hz, 1H, CHAr), 6.59 (dd, J = 8.8 Hz, J = 2.3 Hz, 1H,
as yellow solid (32 mg, 43 %) with a melting point of 82 – 84 °C.
CHAr), 6.50 (d, 3J = 5.4 Hz, 1H, CHHetar), 1.43 (s, 9H, CH3). 19F NMR
(282 MHz, [D]Chloroform): δ = –105.23. 13C NMR (75 MHz,
3
4
1H NMR (300 MHz, [D]Chloroform): δ = 8.57 (ddd, J = 8.0 Hz, J =
5
3
1
1.7 Hz, J = 0.4 Hz, 1H, CHAr), 7.79 (d, J = 5.5 Hz, 1H, CHHetar), 7.69
(ddd, 3J = 8.7 Hz, 3J = 6.9 Hz, 4J = 1.7 Hz, 1H, CHAr), 7.50 (d, 3J =
8.4 Hz, 1H, CHAr), 7.34 (ddd, 3J = 8.0 Hz, 3J = 6.9 Hz, 4J = 1.0 Hz, 1H,
CHAr), 7.18 (d, 3J = 5.5 Hz, 1H, CHHetar), 4.37 – 4.30 (m, 2H, CH2),
1.93 – 1.77 (m, 2H, CH2), 1.57 – 1.41 (m, 2H, CH2), 1.01 (t, 3J = 7.3 Hz,
3H, CH3). 13C NMR (75 MHz, [D]Chloroform): δ = 173.2 (CO), 147.3
(CAr), 140.9 (CAr), 134.9 (CHHetar), 132.9 (CHAr), 127.6 (CHAr), 123.6
(CAr), 122.9 (CAr), 122.5 (CHAr), 117.2 (CHHetar), 114.8 (CHAr), 48.7
[D]Chloroform): δ = 172.2 (CO), 165.0 (d, JCF = 250.8 Hz, CF), 153.4
3
(CAr), 148.2 (CAr), 143.8 (d, JCF = 11.8 Hz, CAr), 136.4 (CAr), 133.8
(CHHetar), 129.4 (d, 3JCF = 10.8 Hz, CHAr), 128.2 (2CHAr), 127.9 (2CHAr),
4
121.9 (CAr), 119.3 (d, JCF = 1.5 Hz, CAr), 118.6 (CHHetar), 111.2 (d,
2JCF = 23.4 Hz, CHAr), 102.5 (d, 2JCF = 27.1 Hz, CHAr), 35.1 (CtBu), 31.4
(3CH3). IR (ATR, cm–1): ν = 2960 (w), 2868 (w), 1630 (m), 1593 (m),
˜
1508 (m), 1474 (s), 1300 (m), 1259 (m), 1208 (m), 1167 (m), 1089
(m), 1054 (m), 990 (m), 839 (m), 762 (s). MS (EI, 70 eV): m/z (%) =
(CH2), 30.6 (CH2), 20.7 (CH2), 14.3 (CH3). IR (ATR, cm–1): ν = 3056 (m), 353 (7), 352 (24), 351 ([M]+, 100), 338 (5), 337 (17), 336 (74), 321
˜
2962 (m), 2931 (m), 2869 (m), 1616 (m), 1579 (s), 1556 (m), 1525
(m), 1500 (m), 1463 (m), 1380 (m), 1267 (m), 1182 (m), 1110 (m),
1085 (m), 883 (m), 823 (m), 786 (m), 750 (s). MS (EI, 70 eV): m/z (%) =
258 (8), 257 ([M]+, 47), 216 (5), 215 (14), 214 (100), 201 (9), 186 (15),
172 (7), 128 (5), 115 (5). HRMS (ESI): Calculated for C15H15O1N1S1 [M
+ H]+ 258.09471 found 258.09457.
(5), 308 (17), 218 (5), 190 (7), 154 (14). HRMS (EI): Calculated for
C21H18O1N1F1S1 [M]+ 351.10876 found 351.10819.
4-(4-tert-Butylphenyl)-7-methoxythieno[3,2-b]quinolin-9(4H)-
one 4t
Compound 4s was synthesized according to the general procedure
as pale yellow solid (60 mg, 62 %) with a melting point of 267 –
4-(4-tert-Butylphenyl)-2-methylthieno[3,2-b]quinolin-9(4H)-
one 4q
1
4
269 °C. H NMR (250 MHz, [D]Chloroform): δ = 7.91 (d, J = 3.0 Hz,
1H, CHAr), 7.65 – 7.59 (m, 2H, CHAr), 7.56 (d, 3J = 5.5 Hz, 1H, CHHetar),
7.33 – 7.26 (m, 2H, CHAr), 7.12 (dd, 3J = 9.3 Hz, 4J = 3.0 Hz, 1H, CHAr),
6.90 (d, 3J = 9.3 Hz, 1H, CHAr), 6.50 (d, 3J = 5.5 Hz, 1H, CHHetar), 3.90
(s, 3H, OCH3), 1.41 (s, 9H, CH3). 13C NMR (63 MHz, [D]Chloroform):
δ = 172.4 (CO), 155.3 (CAr), 153.0 (CAr), 147.4 (CAr), 137.0 (CAr), 136.8
(CAr), 133.4 (CHHetar), 128.3 (2CHAr), 127.5 (2CHAr), 123.2 (CAr), 122.9
(CHAr), 121.0 (CAr), 118.4 (CHAr), 118.4 (CHHetar), 105.1 (CHAr), 55.8
Compound 4q was synthesized according to the general procedure
as pale yellow solid (67 mg, 69 %) with a melting point of 296 –
299 °C. 1H NMR (250 MHz, [D]Chloroform): δ = 8.54 (dd, 3J = 8.1 Hz,
4J = 1.4 Hz, 1H, CHAr), 7.72 – 7.59 (m, 2H, CHAr), 7.47 (ddd, 3J =
3
4
8.6 Hz, J = 7.0 Hz, J = 1.7 Hz, 1H, CHAr), 7.35 – 7.23 (m, 3H, CHAr),
6.92 (d, 3J = 8.2 Hz, 1H, CHAr), 6.19 (q, 4J = 1.0 Hz, 1H, CHHetar),
4
2.49 (d, J = 1.0 Hz, 3H, CH3), 1.44 (s, 9H, CH3). 13C NMR (63 MHz,
(OCH3), 35.0 (CtBu), 31.4 (3CH3). IR (ATR, cm–1): ν = 2962 (w), 2867
˜
[D]Chloroform): δ = 172.2 (CO), 153.0 (CAr), 149.7 (CAr), 148.2 (CAr),
(w), 1593 (m), 1511 (m), 1492 (s), 1471 (m), 1367 (m), 1302 (m), 1267
142.0 (CAr), 136.8 (CAr), 131.7 (CHAr), 128.4 (2CHAr), 127.6 (2CHAr), (m), 1229 (m), 1151 (m), 1115 (m), 1037 (m), 1028 (m), 810 (m), 731
126.3 (CHAr), 122.6 (CAr), 122.3 (CHAr), 120.3 (CAr), 116.8 (CHHetar),
(s). MS (EI, 70 eV): m/z (%) = 365 (7), 364 (24), 363 ([M]+, 100), 362
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HRMS (EI): Calculated for C22H21O2N1S1 [M]+ 363.12875 found
363.12799.
Acknowledgments
Financial support by the state of Mecklenburg-Vorpommern is
gratefully acknowledged.
[13]
Keywords: Catalysis · Cyclization · Heterocycles ·
Palladium · Regioselectivity
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Received: August 22, 2019
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