Regioselective synthesis of 5-(arylsulfanyl)- and 5-(benzylsulfanyl)-6- phenylsalicylates by one-pot cyclizations of 1,3-bis(silyloxy)buta-1,3-dienes with 2-(arylsulfanyl)- and 5-(benzylsulfanyl)-3-ethoxy-1-phenylprop-2-en-1-ones

Article abstract of DOI:10.1002/hlca.200900393

5-(Arylsulfanyl)-6-phenylsalicylates were prepared by one-pot cyclizations of 1,3-bis(trimethylsilyloxy) buta-1,3-dienes with 2-(arylsulfanyl)-3-ethoxy-1- phenylprop-2-en-1-ones.

Full text of DOI:10.1002/hlca.200900393

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Helvetica Chimica Acta – Vol. 93 (2010)
Regioselective Synthesis of 5-(Arylsulfanyl)- and 5-(Benzylsulfanyl)-6-
phenylsalicylates by One-Pot Cyclizations of 1,3-Bis(silyloxy)buta-1,3-dienes
with 2-(Arylsulfanyl)- and 5-(Benzylsulfanyl)-3-ethoxy-1-phenylprop-2-en-1-
ones
by Olumide Fatunsina), Mohanad Shkoora), Abdolmajid Riahia), Munawar Hussaina),
Alexander Villingerb), Christine Fischerb), and Peter Langer*a)b)
a) Institut fꢀr Chemie, Universitꢁt Rostock, Albert-Einstein-Strasse 3a, DE-18059 Rostock
(fax: þ 493814986412; e-mail: peter.langer@uni-rostock.de)
b) Leibniz-Institut fꢀr Katalyse e.V. an der Universitꢁt Rostock, Albert-Einstein-Strasse 29a,
DE-18059 Rostock
5-(Arylsulfanyl)-6-phenylsalicylates were prepared by one-pot cyclizations of 1,3-bis(trimethylsilyl-
oxy)buta-1,3-dienes with 2-(arylsulfanyl)-3-ethoxy-1-phenylprop-2-en-1-ones.
1. Introduction. – Natural and non-natural diaryl sulfides (diaryl thioethers) are of
pharmacological relevance and have been isolated as natural products (for dibenzo-
thiophenes, see [1a]; for lissoclinotoxins (varacins), see [1b][1c][1d]; for lissoclibadins,
see [1e][1f]; for cyclo(penta-1,4-phenylenesulfide) and cyclotetra(p-phenylenesul-
fide), see [1g]; and for natural products isolated from Streptomyces griseus, see [1h]).
For example, fluorinated diaryl sulfides have been reported to act as serotonin
transporter ligands [2]. Diaryl sulfides have been prepared mainly by formation of a
CꢀS bond. This includes, for example, the reaction of copper thiolates with aryl halides.
An alternative relies on the reduction of aryl sulfones or aryl sulfoxides. All these
methods are often limited by the harsh conditions, required by the formation of
polysulfides, preparative scope, use of toxic reagents (such as HMPTA), or low
regioselectivity (for the thermal reaction of arenes with sulfur, see, e.g., [3a][3b]; for
the trifluoromethanesulfonic acid-catalyzed sulfurization of cycloalkanes, see [3c];
for condensations of organometallic compounds with chlorophenyl sulfide, see, e.g.,
[3d]; and for base-mediated reactions of chloroarenes with thiophenols, see
[3e][3f][3g][3h]). Mild metal-catalyzed and metal-free reactions for the synthesis
of diaryl sulfides have also been reported [4 – 6]. These methods are often limited by
the fact that highly substituted and sterically encumbered products are not readily
available. In addition, the synthesis of the starting materials, substituted arenes and
thiophenols, can be difficult.
The use of S-containing building blocks in cyclization reactions (building-block
approach) provides an alternative procedure to diaryl sulfides. This approach involves
the assembly of the arene moiety by formation of two CꢀC bonds. Hilt and co-workers
reported an efficient synthesis of diaryl sulfides by CoI-catalyzed [4 þ 2] cycloaddition
ꢂ 2010 Verlag Helvetica Chimica Acta AG, Zꢀrich

Helvetica Chimica Acta – Vol. 93 (2010)
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of alkynyl sulfides with buta-1,3-dienes [7]. Syntheses of 2-(arylsulfanyl)benzoates and
related products by cyclization reactions of (arylsulfanyl)-1-(trimethylsilyloxy)buta-
1,3-dienes were reported by Chan and Prasad [8], by us [9], and by others [10].
Recently, we reported [11] the synthesis of 3- and 5-(arylsulfanyl)salicylates based on
formal [3 þ 3] cyclizations [12] of 1,3-bis(trimethylsilyloxy)buta-1,3-dienes with 3-
(silyloxy)prop-2-en-1-ones and 1,1-diacetylcyclopropane [12]. Despite the usefulness
of these reactions, they are limited by the fact that, in most cases, only symmetrical 1,3-
dielectrophiles can be employed. In addition, a Me group must generally be present at
4-position. Here, we report, to the best of our knowledge, the first synthesis of 6-aryl-5-
(arylsulfanyl)salicylates unsubstituted at C(4) by one-pot cyclizations of 1,3-bis(trime-
thylsilyloxy)buta-1,3-dienes with 2-(arylsulfanyl)-3-ethoxy-1-phenylprop-2-en-1-ones.
2. Results and Discussion. – The novel 2-(arylsulfanyl)-3-ethoxy-1-phenylprop-2-
en-1-ones 3a – 3f were prepared by reaction of a-bromoacetophenone with thiophenols
1a – 1f to give 2a – 2f (Scheme 1 and Table 1). The reaction of the latter with triethyl
orthoformate HC(OEt)3 afforded the 2-(arylsulfanyl)-3-ethoxy-1-phenylprop-2-en-1-
ones 3a – 3f.
Scheme 1. Synthesis of 3a – 3f
i) EtONa (1.0 equiv.), 2-bromoacetophenone (1.0 equiv.), 1a – 1f (1.0 equiv.). ii) 2a – 2f (1.0 equiv.),
HC(OEt)3 (3 equiv.), Ac2O (3 equiv.), reflux, 15 h at 1408; products exist as mixtures of (E)- and (Z)-
isomers.
Table 1. Synthesis of 3a – 3f
1 – 3
Ar
Yield [%]a)
2
3
a
b
c
d
e
f
Ph
95
98
92
99
99
96
41
54
55
45
42
50
4-MeꢀC6H4
4-FꢀC6H4
4-NO2ꢀC6H4
PhCH2
Naphthalen-2-yl
a) Yields of isolated products.
The [3 þ 3] cyclization of 1,3-bis(trimethylsilyloxy)buta-1,3-diene 4a, prepared in
two steps from methyl acetoacetate, with 3a afforded the novel 5-(phenylsulfanyl)-6-
phenylsalicylates 5a in 44% yield (Scheme 2). The best yield was obtained when the
reaction was carried out in highly concentrated solution, and when TiCl4 was employed
as Lewis acid. It is worthy to be noted that the cyclization proceeded with excellent

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Helvetica Chimica Acta – Vol. 93 (2010)
regioselectivity. The moderate yield of 5a can be explained by practical problems
during the chromatographic purification. The formation of the other regioisomer was
not observed.
Scheme 2. Possible Mechanism of the Formation of 5a
The formation of product 5a can be explained by reaction of 3a with TiCl4 to give
intermediate A, attack of the terminal C-atom of 4a onto A, resulting in intermediate
B, formation of intermediate C, cyclization via the central C-atom (intermediate D),
and subsequent aromatization. The regioselectivity of the formation of 5a might be
explained by steric hindrance at the ketone CO group.
The [3 þ 3] cyclization of 1,3-bis(trimethylsilyloxy)buta-1,3-dienes 4a – 4g, pre-
pared in two steps from the corresponding b-keto esters, with 3a – 3f afforded the novel
5-(arylsulfanyl)-6-phenylsalicylates 5a – 5q (Scheme 3 and Table 2). The reactions
could be successfully carried out with 2-(arylsulfanyl)-3-ethoxy-1-phenylprop-2-en-1-
ones containing electron-donating or electron-withdrawing groups. Cyclizations of 1,3-
bis(trimethylsilyloxy)buta-1,3-dienes 4b – 4g, containing a substituent at the terminal
C-atom, gave slightly higher yields than the reactions of unsubstituted derivative 4a.
The synthesis of product 5p showed that the method can be successfully applied for the
preparation of 5-(benzylsulfanyl)salicylates.
The structures of all products were confirmed by spectroscopic methods (HMBC,
NOESY). The structures of products 5a and 5i, which contain a H-atom at C(3), are
evident by Jo ¼ 8.8 and 8.7 Hz, respectively. The structure of 5j was independently
confirmed by an X-ray crystal structure analysis (Fig.) [13].
In conclusion, a variety of 5-(arylsulfanyl)-6-phenylsalicylates were prepared by
one-pot cyclizations of 1,3-bis(trimethylsilyloxy)buta-1,3-dienes with 2-(arylsulfanyl)-
3-ethoxy-1-phenylprop-2-en-1-ones. The products are not readily available by other
methods.

Helvetica Chimica Acta – Vol. 93 (2010)
Scheme 3. Synthesis of 5a – 5q
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Table 2. Synthesis of 5a – 5q
3
4
5
Ar
R
Yield of 5a) [%]
a
a
a
a
b
b
c
a
c
f
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
Ph
Ph
Ph
Ph
H
Et
44
48
51
52
37
38
43
45
35
48
40
48
42
45
50
47
52
Octyl
Decyl
Et
Decyl
Me
Decyl
H
Me
g
c
g
b
g
a
b
c
d
e
f
4-MeꢀC6H4
4-MeꢀC6H4
4-FꢀC6H4
4-FꢀC6H4
4-NO2ꢀC6H4
4-NO2ꢀC6H4
4-NO2ꢀC6H4
4-NO2ꢀC6H4
4-NO2ꢀC6H4
4-NO2ꢀC6H4
4-NO2ꢀC6H4
PhCH2
c
d
d
d
d
d
d
d
e
f
Et
Pentyl
Hexyl
Octyl
Decyl
Et
g
c
c
Naphthalen-2-yl
Et
a) Yields of isolated products.
Experimental Part
General. All solvents were dried by standard methods, and all reactions were carried out under an
inert atmosphere. Prep. scale column chromatography (CC): silica gel (SiO2; 60 – 200 mesh, Merck) with
heptane/AcOEt as eluent were used. M.p.: Microheating table HMK 67/1825 Kuestner (Bꢀchi
.
apparatus); uncorrected. IR Spectra: Nicolet 380 FT-IR spectrometer; in cmꢀ1 1H- and 13C-NMR
spectra: Bruker AVANCE 300 III and Bruker AVANCE 250 II spectrometer; in CDCl3 at 300 and
75 MHz, resp. EI-MS and HR-EI-MS: MAT 95-XP instrument; in m/z.
General Procedure for the Synthesis of 2a – 2f (GP 1). To a suspension of EtONa (1.0 equiv.) in
EtOH (0.7 ml per 1 mmol of EtONa) was added 1 (1.0 equiv.) at 258, followed by portionwise addition of
2-bromoacetophenone (1.0 equiv.). The mixture was heated to reflux for 10 min and poured into 2 l of
ice-water. Filtration of the suspension gave the respective product 2.
1-Phenyl-2-(phenylsulfanyl)ethanone (2a). GP 1 with EtONa (1.361 g, 20.0 mmol), 1a (2.20 g,
20.0 mmol), and 2-bromoacetophenone (4.00 g, 20.0 mmol): 2a (4.286 g, 93%). Brown semi-solid. IR
(KBr): 3339w, 3057w, 2902w, 1675s, 1596m, 1579m, 1480m, 1447m, 1438m, 1412w, 1394w, 1317m, 1273s,
1197m, 1158m, 1088m, 1024m, 999m, 932w, 906w, 843w, 736s, 685s, 641s, 616m, 555m. 1H-NMR: 4.20 (s,

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Helvetica Chimica Acta – Vol. 93 (2010)
Figure. Crystal structure of 5j
CH2); 7.13 – 7.24 (m, 3 arom. H); 7.29 – 7.33 (m, 2 arom. H); 7.36 – 7.41 (m, 2 arom. H); 7.48 – 7.53 (m, 1
arom. H); 7.85 – 7.89 (m, 2 arom. H). 13C-NMR: 41.2 (CH2); 127.1 (arom. CH); 128.7 (4 arom. CH); 129.1
(2 arom. CH); 130.6 (2 arom. CH); 133.5 (arom. CH); 134.8, 135.4 (arom. C); 194.1 (CO). GC/EI-MS
(70 eV): 228 (39, Mþ), 123 (8), 105 (100), 77 (32), 65 (6), 51 (10). HR-EI-MS: 228.0603 (Mþ, C14H12OSþ;
calc. 228.0603).
2-[(4-Methylphenyl)sulfanyl]-1-phenylethanone (2b). GP 1 with EtONa (1.361 g, 20.0 mmol), 1b
(2.484 g, 20.0 mmol), and 2-bromoacetophenone (4.00 g, 20.0 mmol): 2b (4.773 g, 98%). Brown semi-
solid. IR (neat): 3340w, 3055w, 2918w, 2732w, 1675s, 1593m, 1475m, 1447m, 1317m, 1273s, 1195m, 1134m,
1035w, 987m, 854m, 748m, 685s, 641m, 623w, 610w, 557m. 1H-NMR: 2.22 (s, Me); 4.19 (s, CH2); 6.94 – 6.96
(m, 1 arom. H); 7.09 – 7.13 (m, 3 arom. H); 7.35 – 7.40 (m, 2 arom. H); 7.47 – 7.52 (m, 1 arom. H); 7.85 – 7.88
(m, 2 arom. H). 13C-NMR: 21.3 (Me); 41.3 (CH2); 127.5, 128.0 (arom. CH); 128.6 (2 arom. CH); 128.7 (2
arom. CH); 128.9, 131.2, 133.4 (arom. CH); 134.5, 135.5, 138.9 (arom. C); 194.1 (CO). GC/EI-MS
(70 eV): 242 (45, Mþ), 137 (14), 105 (100), 91 (9), 77 (30), 65 (7), 51 (7). HR-EI-MS: 242.0765 (Mþ,
C15H14OSþ; calc. 242.0760).
2-[(4-Fluorophenyl)sulfanyl]-1-phenylethanone (2c). GP 1 with EtONa (1.361 g, 20.0 mmol), 1c
(2.563 g, 20.0 mmol), and 2-bromoacetophenone (4.00 g, 20.0 mmol): 2c (4.554 g, 92%). Slightly brown
oil. IR (neat): 3338w, 3062w, 2905w, 1675s, 1589m, 1580m, 1489s, 1448m, 1396m, 1274m, 1221s, 1196s,
1
1156m, 1090m, 1000m, 932w, 826m, 748m, 687s, 646m, 625m, 557m. H-NMR: 4.22 (s, CH2); 6.97 – 7.03
(m, 2 arom. H); 7.39 – 7.44 (m, 2 arom. H); 7.46 – 7.52 (m, 2 arom. H); 7.59 – 7.64 (m, 1 arom. H); 7.93 – 7.96
(m, 2 arom. H). 13C-NMR: 42.1 (CH2); 116.2 (d, 2J(C,F) ¼ 22.0); 128.7 (4 arom. CH); 129.4 (arom. C);
133.5 (arom. CH); 133.9 (d, 3J(C,F) ¼ 8.2); 135.3 (arom. C); 162.5 (d, 1J(C,F) ¼ 247.8); 193.9 (CO). 19F-
NMR (285 MHz, CDCl3): ꢀ 113.5. GC/EI-MS (70 eV): 246 (30, Mþ), 141 (4), 127 (5), 105 (100), 83 (6),
77 (33), 51 (8). HR-EI-MS: 246.0509 (Mþ, C14H11FOSþ; calc. 246.0509).
2-[(4-Nitrophenyl)sulfanyl]-1-phenylethanone (2d). GP 1 with EtONa (1.361 g, 20 mmol), 1d
(3.104 g, 20 mmol), and 2-bromoacetophenone (4.00 g, 20 mmol): 2d (5.438 g, 99%). Brown solid.

Helvetica Chimica Acta – Vol. 93 (2010)
1615
M.p. 150 – 1528. IR (neat): 3370w, 3094w, 3062w, 2918w, 2850w, 1677m, 1594m, 1575s, 1502s, 1448m,
1392m, 1334s, 1276m, 1196m, 1108m, 1069m, 988m, 906w, 852m, 755m, 737s, 680s, 623m, 610m, 566m,
1
537m. H-NMR: 4.37 (s, CH2); 7.33 – 7.36 (m, 2 arom. H); 7.41 – 7.46 (m, 3 arom. H); 7.90 – 7.93 (m, 2
arom. H); 8.03 – 8.06 (m, 2 arom. H). 13C-NMR: 39.1 (CH2); 124.0 (2 arom. CH); 127.2 (2 arom. CH);
128.6 (2 arom. CH); 128.9 (2 arom. CH); 134.0 (arom. CH); 134.9, 145.4, 145.7 (arom. C); 192.7 (CO).
GC/EI-MS (70 eV): 273 (8, Mþ), 105 (100), 77 (30), 51 (6). HR-EI-MS: 273.0457 (Mþ, C14H11NO3Sþ;
calc. 273.0454).
2-(Benzylsulfanyl)-1-phenylethanone (2e). GP 1 with EtONa (1.361 g, 20.0 mmol), 1e (2.484 g,
20.0 mmol), and 2-bromoacetophenone (4.00 g, 20.0 mmol): 2e (4.828 g, 99%). Semi-brown solid. IR
(neat): 3648w, 3327w, 3083w, 3059w, 3027w, 2919w, 2626w, 2321w, 1964w, 1900w, 1813w, 1766w, 1670s,
1596m, 1579m, 1493m, 1447m, 1417w, 1315m, 1275s, 1197m, 1130m, 1071m, 1013m, 932w, 803w, 748m,
1
698s, 686s, 645m, 618w, 588w, 561m. H-NMR: 3.70 (s, CH2); 3.79 (s, CH2); 7.28 – 7.32 (m, 2 arom. H);
7.34 – 7.38 (m, 3 arom. H); 7.46 – 7.52 (m, 2 arom. H); 7.57 – 7.62 (m, 1 arom. H); 7.94 – 7.98 (m, 2 arom. H).
13C-NMR: 35.9, 36.1 (CH2); 127.3 (arom. CH); 128.5 (2 arom. CH); 128.6 (2 arom. CH); 128.7 (2 arom.
CH); 129.3 (2 arom. CH); 133.3 (arom. CH); 135.4, 137.3 (arom. C); 194.5 (CO). GC/EI-MS (70 eV):
242 (15, Mþ), 120 (70), 105 (100), 91 (45), 77 (39), 65 (12), 51 (11). HR-EI-MS: 242.0763 (Mþ,
C15H14OSþ; calc. 242.0760).
2-[(Naphthalen-2-yl)sulfanyl]-1-phenylethanone (2f). GC 1 with EtONa (1.361 g, 20.0 mmol), 1f
(3.205 g, 20.0 mmol), and 2-bromoacetophenone (4.00 g, 20.0 mmol): 2f (5.389 g, 96%). Semi-brown
solid. IR (neat): 3328w, 3104w, 3052w, 2985w, 2943w, 2902w, 2853w, 1971w, 1954w, 1916w, 1828w, 1686m,
1668m, 1621m, 1578m, 1498m, 1446m, 1417w, 1338w, 1270m, 1194m, 1130m, 1068m, 1012m, 941m, 846m,
814s, 738s, 686s, 651m, 626m, 599w, 553m. 1H-NMR: 4.29 (s, CH2); 7.35 – 7.40 (m, 5 arom); 7.63 – 7.75 (m, 5
arom); 7.86 – 7.89 (m, 2 arom. H). 13C-NMR: 41.2 (CH2); 126.2, 126.6, 127.4, 127.7, 128.0, 128.6 (arom.
CH); 128.7 (4 arom. CH); 128.9 (arom. CH); 132.2 (arom. C); 133.5 (arom. CH); 133.7, 134.0, 135.5
(arom. C); 194.1 (CO). GC/EI-MS (70 eV): 278 (88, Mþ), 173 (29), 129 (11), 115 (20), 105 (100), 77
(26), 51 (6). HR-EI-MS: 278.0762 (Mþ, C18H14OSþ; calc. 278.076).
General Procedure for the Synthesis of 3a – 3f (GP 2). To a soln. of 2a – 2f (1 equiv.) in Ac2O
(3 equiv.) was added HC(OEt)3 (3.0 equiv.). The mixture was heated for 15 h at 1408. The mixture was
dried in vacuo and was purified by chromatography (SiO2) to give 3.
3-Ethoxy-1-phenyl-2-(phenylsulfanyl)prop-2-en-1-one (3a). GP 2 with 2a (2.00 g, 8.8 mmol),
HC(OEt)3 (3.90 g, 26.3 mmol), and Ac2O (2.68 g, 26.3 mmol): 3a (1.013 g, 41%). Yellowish oil. IR
(neat): 3057w, 2981w, 2935w, 2895w, 1644m, 1588s, 1475m, 1439m, 1390m, 1297m, 1212s, 1178m, 1089m,
1009m, 892m, 822m, 737m, 688s, 657s, 616m, 577m, 541m. 1H-NMR: 1.25 (t, 3J ¼ 7.1, MeCH2O); 4.09 (q,
3J ¼ 7.1, MeCH2O); 6.99 – 7.04 (m, 1 arom. H); 7.09 – 7.12 (m, 1 arom. H); 7.13 – 7.19 (m, 3 arom. H); 7.28 –
7.34 (m, 2 arom. H); 7.38 – 7.44 (m, 1 arom. H); 7.55 – 7.58 (m, 3 arom. H). 13C-NMR: 15.3 (Me); 71.8
(CH2O); 112.3 (C); 125.7 (arom. CH); 128.1 (4 arom. CH); 128.7 (2 arom. CH); 128.8 (2 arom. CH);
131.5 (arom. CH); 135.8, 138.9 (arom. C); 166.4 (C); 193.5 (CO). GC/EI-MS (70 eV): 284 (100, Mþ), 255
(6), 149 (10), 135 (6), 121 (15), 105 (90), 77 (46), 51 (10). HR-EI-MS: 284.0860 (Mþ, C17H16O2Sþ; calc.
284.0866).
3-Ethoxy-2-[(4-methylphenyl)sulfanyl]-1-phenylprop-2-en-1-one (3b). GP 2 with 2b (2.00 g,
8.3 mmol), HC(OEt)3 (3.67 g, 24.7 mmol), and Ac2O (2.53 g, 24.7 mmol): 3b (1.333 g, 54%). Yellowish
oil. 1H-NMR: 1.25 (t, 3J ¼ 7.1, MeCH2O); 2.18 (s, Me); 4.10 (q, 3J ¼ 7.1, MeCH2O); 6.96 – 7.00 (m, 2 arom.
H); 7.28 – 7.34 (m, 2 arom. H); 7.38 – 7.43 (m, 2 arom. H); 7.53 – 7.58 (m, 3 arom. H); 7.82 – 7.85 (m, 1 arom.
H). 13C-NMR: 15.4, 21.3 (Me); 71.7 (CH2O); 112.3 (C); 125.1, 126.6, 127.7, 128.1, 128.6, 128.8, 128.9,
131.5, 133.9 (arom. CH); 135.4, 138.4, 139.0 (arom. CH); 166.3 (CH); 192.1 (CO). IR (neat): 3057w,
2980w, 2930w, 1749m, 1703m, 1645m, 1591s, 1447m, 1370m, 1272m, 1214s, 1180m, 1085m, 1011m, 893m,
822m, 755m, 687s, 658m, 617w, 562m, 542w. GC/EI-MS (70 eV): 298 (100, Mþ), 149 (12), 135 (11), 123
(9), 105 (88), 91 (9), 77 (40), 51 (6). HR-EI-MS: 298.1016 (Mþ, C18H18O2Sþ; calc. 298.1022).
3-Ethoxy-2-[(4-fluorophenyl)sulfanyl]-1-phenylprop-2-en-1-one (3c). GP 2 with 2c (2.00 g,
8.1 mmol), HC(OEt)3 (3.61 g, 24.4 mmol), and Ac2O (2.49 g, 24.4 mmol): 3c (1.351 g, 55%). Brownish
oil. IR (neat): 3062w, 2982w, 2936w, 2896w, 2816w, 1749w, 1704w, 1644m, 1586s, 1487s, 1445m, 1392m,
1334w, 1272m, 1212s, 1153m, 1086m, 1010s, 928w, 822m, 755w, 657m, 625m, 562w. 1H-NMR: 1.26 (t, 3J ¼
7.1, MeCH2O); 4.09 (q, 3J ¼ 7.1, MeCH2O); 6.79 – 6.85 (m, 2 arom. H); 7.16 – 7.21 (m, 2 arom. H); 7.29 –

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Helvetica Chimica Acta – Vol. 93 (2010)
7.34 (m, 2 arom. H); 7.39 – 7.44 (m, 1 arom. H); 7.48 (s, CH); 7.52 – 7.56 (m, 2 arom. H). 13C-NMR: 15.4
(Me); 71.8 (CH2O); 113.2 (C); 115.8 (d, 2J(C,F) ¼ 22.0); 128.2 (2 arom. CH); 128.8 (2 arom. CH); 131.1
(d, 3J(C,F) ¼ 8.1); 130.7 (arom. C); 131.6 (arom. CH); 138.9 (arom. C); 161.6 (d, 1J(C,F) ¼ 245.5); 165.9
(CH); 193.3 (CO). 19F-NMR (285 MHz, CDCl3): ꢀ 116.5. GC/EI-MS (70 eV): 302 (100, Mþ), 273 (5),
127 (12), 105 (94), 77 (43), 51 (7). HR-EI-MS: 302.0774 (Mþ, C17H15FO2Sþ; calc. 302.0771).
3-Ethoxy-2-[(4-nitrophenyl)sulfanyl]-1-phenylprop-2-en-1-one (3d). GP 2 with 2d (2.00 g,
7.3 mmol), HC(OEt)3 (3.25 g, 22.0 mmol), and Ac2O (2.24 g, 22.0 mmol): 3d (1.078 g, 45%). Yellowish
oil. IR (neat): 3272w, 3092w, 3011w, 2951w, 2891w, 2605w, 2440w, 1672m, 1643m, 1592m, 1574s, 1558s,
1500s, 1471m, 1386m, 1332s, 1314s, 1217s, 1175s, 1109m, 1013s, 934m, 910s, 844s, 794m, 717s, 697s, 681s,
659m, 645s, 625m, 565m, 541m. 1H-NMR: 1.27 (t, 3J ¼ 7.1, MeCH2O); 4.15 (q, 3J ¼ 7.1, MeCH2O); 7.19 –
7.22 (m, 2 arom. H); 7.34 – 7.39 (m, 2 arom. H); 7.43 – 7.48 (m, 1 arom. H); 7.58 – 7.61 (m, 2 arom. H); 7.74
(s, 1 arom. H); 7.97 – 8.00 (m, 2 arom. H). 13C-NMR: 15.4 (Me); 72.5 (CH2O); 109.3 (C); 123.9 (2 arom.
CH); 126.2 (2 arom. CH); 128.4 (2 arom. CH); 128.8 (2 arom. CH); 132.0 (arom. CH); 138.4, 145.2, 146.4
(arom. C); 168.7 (CH); 192.6 (CO). GC/EI-MS (70 eV): 329 (68, Mþ), 300 (8), 255 (6), 197 (6), 165 (6),
105 (100), 77 (27), 50 (7). HR-EI-MS: 329.0718 (Mþ, C17H15NO4Sþ); calc. 329.0716).
2-(Benzylsulfanyl)-3-ethoxy-1-phenylprop-2-en-1-one (3e). GP 2 with 2e (2.00 g, 8.3 mmol),
HC(OEt)3 (3.67 g, 24.8 mmol), and Ac2O (2.53 g, 24.8 mmol): 3e (1.033 g, 42%). Yellowish oil. IR
(neat): 3060w, 3028w, 2978w, 2924w, 1750w, 1704w, 1672m, 1596m, 1492m, 1447m, 1340m, 1275m, 1217m,
1179m, 1071m, 1014m, 967m, 843m, 765m, 696s, 687s, 646m, 618m, 563m, 540m. 1H-NMR: 1.19 (t, 3J ¼ 7.1,
MeCH2O); 3.90 – 3.97 (m, CH2, MeCH2O); 7.13 – 7.19 (m, 5 arom. H); 7.26 – 7.28 (m, 4 arom. H); 7.36 –
7.41 (m, 2 arom. H). 13C-NMR: 15.3 (Me); 36.7 (CH2); 71.3 (CH2O); 112.3 (C); 126.8 (arom. CH); 128.0
(2 arom. CH); 128.1 (2 arom. CH); 128.8 (2 arom. CH); 129.3 (2 arom. CH); 131.2 (arom. CH); 138.3,
139.3 (arom. C); 166.1 (CH); 193.6 (CO). GC/EI-MS (70 eV): 298 (Mþ, 34); 252 (30), 147 (51), 131 (10),
105 (79), 91 (100), 77 (49), 65 (13), 51 (8), 39 (8). HR-EI-MS: 298.1026 (Mþ, C18H18O2Sþ; calc.
298.1022).
3-Ethoxy-2-[(naphthalen-2-yl)sulfanyl]-1-phenylprop-2-en-1-one (3f). GP 2 with 2f (2.00 g,
7.2 mmol), HC(OEt)3 (3.19 g, 21.5 mmol), and Ac2O (2.20 g, 21.5 mmol): 3f (1.201 g, 50%). Yellowish
oil. IR (neat): 3053w, 2979w, 2930w, 1749m, 1703m, 1644m, 1587m, 1500m, 1446m, 1339m, 1268m, 1215s,
1132m, 1086m, 1012m, 940m, 847m, 811s, 743m, 688s, 632m, 617m, 601m, 575m, 541m. 1H-NMR: 1.24 (t,
3
3J ¼ 7.1, MeCH2O); 4.11 (q, J ¼ 7.1, MeCH2O); 7.26 – 7.43 (m, 7 arom. H); 7.58 – 7.67 (m, 6 arom. H).
13C-NMR: 15.4 (Me); 71.8 (CH2O); 112.1 (C); 125.4, 126.2, (arom. CH); 126.3 (2 arom. CH); 127.1, 127.6
(arom. CH); 128.1 (2 arom. CH); 128.3 (arom. CH); 128.8 (2 arom. CH); 131.5 (arom. CH); 131.7, 133.3,
133.7, 138.9 (arom. C); 166.5 (CH); 193.5 (CO). GC/EI-MS (70 eV): 334 (100, Mþ), 159 (12), 115 (16),
105 (76), 77 (31). HR-EI-MS: 334.1022 (Mþ; C21H18O2Sþ; calc. 334.1022).
General Procedure for the Synthesis of 5a – 5q (GP 3). To a CH2Cl2 soln. (3 ml per 1 mmol of 3a – 3f)
of 3a – 3f was added 4a – 4g (1.1 mmol) and, subsequently, TiCl4 (1.1 mmol) at ꢀ 788. The soln. was
allowed to warm to 208 during 14 h with stirring. HCl (10%, 20 ml) was added to the soln., and the org.
and the aq. layer were separated. The latter was extracted with CH2Cl2 (3 ꢁ 20 ml). The combined org.
layers were dried (Na2SO4), filtered, and the filtrate was concentrated in vacuo. The residue was purified
by CC (SiO2) to give 5a – 5q.
Methyl 3-Hydroxy-6-(phenylsulfanyl)-1,1’-biphenyl-2-carboxylate (5a). GC 3 with 3a (0.427 g,
1.5 mmol) and 4a (0.430 g, 1.65 mmol): 5a (0.222 g, 44%). Yellowish oil. IR (neat): 3056w, 3021w,
2950w, 2850w, 2659w, 2536w, 1943w, 1880w, 1739w, 1663s, 1582m, 1496w, 1435s, 1335m, 1288m, 1208s,
1155m, 1094m, 1024m, 964m, 828m, 737s, 698s, 688s, 612m, 575m. 1H-NMR: 3.23 (s, MeO); 6.83 (d, 3J ¼
8.8, 1 arom. H); 6.92 – 6.95 (m, 4 arom. H); 6.99 – 7.05 (m, 3 arom. H); 7.14 – 7.17 (m, 3 arom. H); 7.28 (d,
3J ¼ 8.8, 1 arom. H); 10.67 (s, OH). 13C-NMR: 52.0 (MeO); 113.9 (CCOOMe); 118.2 (arom. CH); 126.1
(arom. C); 126.4, 127.0 (arom. CH); 127.4 (2 arom. CH); 128.5 (2 arom. CH); 128.9 (2 arom. CH); 130.0
(2 arom. CH); 137.3 (arom. C); 139.1 (arom. CH); 140.7, 146.1 (arom. C); 161.1 (COH); 171.0 (CO). GC/
EI-MS (70 eV): 336 (46, Mþ), 304 (100), 275 (8), 247 (17), 215 (8), 171 (17), 139 (10). HR-EI-MS:
336.0811 (Mþ, C20H16O3Sþ; calc. 336.0815).
Methyl 4-Ethyl-3-hydroxy-6-(phenylsulfanyl)-1,1’-biphenyl-2-carboxylate (5b). GP 3 with 3a
(0.427 g, 1.5 mmol) and 4c (0.476 g, 1.65 mmol): 5b (0.263 g, 48%). Yellowish oil. IR (neat): 3057w,
3023w, 2963m, 2951m, 2933w, 2874w, 1933w, 1701m, 1661s, 1598m, 1477m, 1436s, 1409m, 1338m, 1290m,

Helvetica Chimica Acta – Vol. 93 (2010)
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1229s, 1196s, 1161s, 1065m, 1024m, 968m, 907m, 841m, 815m, 737s, 697s, 689s, 628m, 569w, 530m.
1H-NMR: 1.02 (t, 3J ¼ 7.5, MeCH2); 2.50 (q, 3J ¼ 7.7, MeCH2); 3.19 (s, MeO); 6.84 – 6.90 (m, 4 arom. H);
6.96 – 7.03 (m, 2 arom. H); 7.08 – 7.12 (m, 5 arom); 10.89 (s, OH). 13C-NMR: 14.7 (Me); 24.1 (CH2); 53.1
(MeO); 114.6 (CCOOMe); 125.6 (arom. C); 127.1, 128.0 (arom. CH); 128.5 (2 arom. CH); 129.8 (2 arom.
CH); 130.0 (2 arom. CH); 130.3 (2 arom. CH); 134.4, 139.3 (arom. C); 140.2 (arom. CH); 142.2, 145.6
(arom. C); 160.7 (COH); 172.7 (CO). GC/EI-MS (70 eV): 364 (34, Mþ), 332 (100), 223 (37), 205 (11),
184 (7), 165 (14), 110 (9), 78 (11), 63 (9), 40 (31). HR-EI-MS: 364.1127 (Mþ; C22H20O3Sþ; calc.
364.1128).
Methyl 3-Hydroxy-4-octyl-6-(phenylsulfanyl)-1,1’-biphenyl-2-carboxylate (5c). GP 3 with 3a
(0.427 g, 1.5 mmol) and 4f (0.615 g, 1.65 mmol): 5c (0.344 g, 51%). Yellowish oil. IR (neat): 3058w,
3024w, 2952m, 2923m, 2853m, 1934w, 1703m, 1663m, 1598w, 1477w, 1437s, 1410m, 1340m, 1234s, 1197m,
1161m, 1024m, 905w, 842m, 813m, 749m, 698s, 629m, 616w, 596w, 572w, 532w. 1H-NMR: 0.70 (t, 3J ¼ 7.5,
Me(CH2)7); 1.07 – 1.12 (m, 5 CH2); 1.39 – 1.43 (m, CH2); 2.45 (t, 3J ¼ 7.5, Me(CH2)6CH2); 3.19 (s, MeO);
6.84 – 6.90 (m, 4 arom. H); 6.95 – 7.03 (m, 3 arom. H); 7.08 – 7.11 (m, 4 arom. H); 10.87 (s, OH). 13C-NMR:
15.3 (Me); 23.9, 30.2, 30.3, 30.5, 30.6, 30.9, 33.1 (CH2); 53.0 (MeO); 114.6 (CCOOMe); 125.4 (arom. C);
127.0, 128.0 (arom. CH); 128.4 (2 arom. CH); 129.8 (2 arom. CH); 130.0 (2 arom. CH); 130.2 (2 arom.
CH); 133.1, 139.4 (arom. C); 141.1 (arom. CH); 142.2, 145.6 (arom. C); 160.7 (COH); 172.7 (CO). GC/
EI-MS (70 eV): 448 (21, Mþ), 416 (15), 340 (72), 308 (81), 291 (10), 210 (100), 181 (16), 152 (28), 129
(17), 116 (37), 71 (9), 57 (16), 43 (15). HR-EI-MS: 448.2068 (Mþ, C28H32O3Sþ; calc. 448.2067).
Methyl 4-Decyl-3-hydroxy-6-(phenylsulfanyl)-1,1’-biphenyl-2-carboxylate (5d). GP 3 with 3a
(0.427 g, 1.5 mmol) and 4g (0.661 g, 1.65 mmol): 5d (0.372 g, 52%). Yellowish oil. IR (neat): 3058w,
3024w, 2951m, 2922s, 2852m, 1938w, 1745w, 1663m, 1598w, 1582w, 1477m, 1437s, 1410m, 1340m, 1292m,
1234m, 1197m, 1162m, 1072m, 1024m, 999m, 909w, 842w, 813m, 737s, 698s, 689s, 631w, 596w, 572w, 531w.
1H-NMR: 0.71 (t, 3J ¼ 7.1, Me(CH2)9); 1.07 – 1.10 (m, 7 CH2); 1.37 – 1.43 (m, CH2); 2.45 (t, 3J ¼ 7.5,
Me(CH2)8CH2); 3.19 (s, MeO); 6.84 – 6.90 (m, 4 arom. H); 7.00 – 7.12 (m, 7 arom. H); 10.87 (s, OH).
13C-NMR: 14.1 (Me); 22.7, 29.1, 29.3, 29.4, 29.5, 29.6, 29.7, 29.9, 31.9 (CH2); 51.9 (MeO); 113.4
(CCOOMe); 124.2 (arom. C); 125.8, 126.7, 127.2, 127.6, 128.1, 128.6 (arom. CH); 128.8 (2 arom. CH);
129.0 (2 arom. CH); 131.9, 138.2 (arom. C); 139.9 (arom. CH); 141.0, 144.4 (arom. C); 159.5 (COH);
171.5 (CO). GC/EI-MS (70 eV): 476 (14, Mþ), 444 (11), 368 (35), 336 (77), 318 (9), 304 (52), 210 (100),
182 (18), 152 (16), 129 (11), 116 (22), 43 (17). HR-EI-MS: 476.2385 (Mþ, C30H36O3Sþ; calc. 476.2380).
Methyl 4-Ethyl-3-hydroxy-6-[(4-methylphenyl)sulfanyl]-1,1’-biphenyl-2-carboxylate (5e). GP 3 with
3b (0.448 g, 1.5 mmol) and 4c (0.476 g, 1.65 mmol): 5e (0.210 g, 37%). Yellowish oil. IR (neat): 3054w,
3025w, 2963m, 2932m, 2908w, 2873w, 1934w, 1731m, 1662s, 1592m, 1574m, 1436s, 1413m, 1342m, 1289m,
1231s, 1197m, 1163m, 1080m, 1027m, 970m, 907w, 845m, 815m, 774m, 750m, 699s, 689m, 629w. 1H-NMR:
3
3
1.01 (t, J ¼ 7.5, MeCH2); 2.07 (s, Me); 2.49 (q, J ¼ 7.5, MeCH2); 3.20 (s, MeO); 6.65 – 6.73 (m, 2 arom.
H); 6.87 – 6.91 (m, 3 arom. H); 7.08 (s, 1 arom. H); 7.10 – 7.13 (m, 4 arom. H); 10.87 (s, OH). 13C-NMR:
14.8, 22.5 (Me); 24.1 (CH2); 53.1 (MeO); 114.5 (CCOOMe); 125.9 (arom. C); 127.6, 128.0, 128.1 (arom.
CH); 128.5 (2 arom. CH); 128.8, 129.2 (arom. CH); 129.9 (2 arom. CH); 134.3, 134.8, 139.8 (arom. C);
140.0 (arom. CH); 142.2, 145.3 (arom. C); 160.6 (COH); 172.8 (CO). GC/EI-MS (70 eV): 378 (38, Mþ),
346 (100), 254 (17), 223 (62), 205 (13), 184 (9), 165 (25), 124 (12), 105 (11), 91 (31), 77 (16), 44 (30).
HR-EI-MS: 378.1282 (Mþ, C23H22O3Sþ; calc. 378.1284).
Methyl 4-Decyl-3-hydroxy-6-[(4-methylphenyl)sulfanyl]-1,1’-biphenyl-2-carboxylate (5f). GP 3 with
3b (0.448 g, 1.5 mmol) and 4g (0.661 g, 1.65 mmol): 5f (0.280 g, 38%). Yellowish oil. IR (neat): 3055w,
3025w, 2951m, 2922s, 2852m, 1934w, 1749w, 1716w, 1704w, 1662s, 1592m, 1574w, 1437s, 1412m, 1339m,
1291m, 1234s, 1197m, 1162m, 1073w, 998m, 908w, 844m, 813m, 767m, 749m, 698s, 631w, 595w, 542w.
1H-NMR: 0.70 (t, 3J ¼ 7.1, Me(CH2)9); 1.07 – 1.10 (m, 7 CH2); 1.38 – 1.47 (m, CH2); 2.06 (s, Me); 2.45 (t,
3J ¼ 7.6, Me(CH2)8CH2); 3.19 (s, MeO); 6.65 – 6.69 (m, 2 arom. H); 6.87 – 6.90 (m, 3 arom. H); 7.07 – 7.12
(m, 5 arom); 10.86 (s, OH). 13C-NMR: 15.3, 22.5 (Me); 23.9, 30.3, 30.5, 30.6, 30.7, 30.8, 30.9, 31.1, 33.1
(CH2); 53.0 (MeO); 114.5 (CCOOMe); 125.7 (arom. C); 127.5, 128.0 (arom. CH); 128.4 (2 arom. CH);
128.8, 129.3 (arom. CH); 129.8 (2 arom. CH); 131.0 (arom. CH); 133.0, 138.9, 139.7 (arom. C); 140.8
(arom. CH); 142.2, 145.3 (arom. C); 160.6 (COH); 172.7 (CO). GC/EI-MS (70 eV): 490 (5, Mþ), 458 (6),
336 (32), 223 (11), 210 (100), 181 (19), 152 (29), 129 (14), 116 (31), 91 (16), 71 (16), 43 (33). HR-EI-MS:
490.2541 (Mþ, C31H38O3Sþ; calc. 490.2536).

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Helvetica Chimica Acta – Vol. 93 (2010)
Methyl 6-[(4-Fluorophenyl)sulfanyl]-3-hydroxy-4-methyl-1,1’-biphenyl-2-carboxylate (5g). GP 3
with 3c (0.454 g, 1.5 mmol) and 4b (0.453 g, 1.65 mmol): 5g (0.238 g, 43%). Yellowish oil. IR (neat):
3059w, 3025w, 2951w, 2926w, 2902w, 2854w, 1729w, 1664m, 1613w, 1599w, 1488m, 1437m, 1408m, 1338m,
1280m, 1243s, 1228s, 1197m, 1155m, 1086m, 1013m, 943w, 827s, 809s, 760m, 698s, 678m, 628m, 595w, 564w,
548w. 1H-NMR: 2.17 (s, Me); 3.30 (s, MeO); 6.94 – 6.99 (m, 4 arom. H); 7.18 – 7.25 (m, 6 arom. H); 10.98
2
(s, OH). 13C-NMR: 14.9 (Me); 50.9 (MeO); 112.2 (CCOOMe); 115.0 (d, J(C,F) ¼ 21.9); 125.9, 126.3
(arom. CH); 126.4 (arom. C); 126.6, 127.1, 127.7 (arom. CH); 131.1 (d, 3J(C,F) ¼ 8.1); 138.4 (arom. CH);
139.8, 141.3, 141.9, 142.6 (arom. C); 158.6 (COH); 160.7 (d, 1J(C,F) ¼ 246.5); 170.4 (CO). 19F-NMR
(285 MHz, CDCl3): ꢀ 115.6. GC/EI-MS (70 eV): 368 (28, Mþ), 336 (100), 240 (11), 209 (26), 184 (10),
152 (15), 128 (7). HR-EI-MS: 368.0880 (Mþ, C21H17FO3Sþ; calc. 368.0877).
Methyl 4-Decyl-6-[(4-fluorophenyl)sulfanyl]-3-hydroxy-1,1’-biphenyl-2-carboxylate (5h). GP 3 with
3c (0.454 g, 1.5 mmol) and 4g (0.661 g, 1.65 mmol): 5h (0.334 g, 45%). Yellowish oil. IR (neat): 3058w,
3025w, 2951m, 2922s, 2852m, 1935w, 1873w, 1746w, 1704w, 1663m, 1589m, 1556w, 1488s, 1437s, 1409m,
1339m, 1292m, 1227s, 1197m, 1155s, 1085w, 1012w, 999m, 883w, 822m, 749m, 698s, 626m, 598w, 573w.
1H-NMR: 0.71 (t, 3J ¼ 7.1, Me(CH2)9); 1.07 – 1.10 (m, 7 CH2); 1.38 – 1.42 (m, CH2); 2.44 (t, 3J ¼ 7.4,
Me(CH2)8CH2); 3.19 (s, MeO); 6.69 – 6.74 (m, 2 arom. H); 6.83 – 6.89 (m, 4 arom. H); 7.11 – 7.13 (m, 4
arom. H); 10.84 (s, OH). 13C-NMR: 15.3 (Me); 23.9, 30.3, 30.5, 30.6, 30.7 (CH2); 30.8 (2 CH2); 30.9, 33.1
2
(CH2); 53.1 (MeO); 114.6 (CCOOMe); 117.1 (d, J(C,F) ¼ 22.0); 126.3 (arom. C); 127.8 (arom. CH);
128.5 (2 arom. CH); 129.9 (2 arom. CH); 131.1 (d, 3J(C,F) ¼ 8.0); 133.8, 134.9 (arom. C); 140.1 (arom.
CH); 142.1, 144.8 (arom. C); 160.5 (COH); 162.9 (d, 1J(C,F) ¼ 246.0); 172.7 (CO). 19F-NMR (285 MHz,
CDCl3): ꢀ 115.7. GC/EI-MS (70 eV): 494 (100, Mþ), 462 (79), 377 (12), 335 (29), 240 (26), 209 (99), 152
(6), 128 (6). HR-EI-MS: 494.2292 (Mþ, C30H35FO3Sþ; calc. 494.2286).
Methyl 3-Hydroxy-6-[(4-nitrophenyl)sulfanyl]-1,1’-biphenyl-2-carboxylate (5i). GP 3 with 3d
(0.494 g, 1.5 mmol) and 4a (0.430 g, 1.65 mmol): 5i (0.200 g, 35%). Yellowish oil. IR (neat): 3093w,
3060w, 3024w, 2959w, 2924w, 2852w, 1737w, 1666m, 1574m, 1510m, 1476w, 1437m, 1334s, 1259m, 1214m,
1083m, 1012m, 902w, 852m, 796m, 741m, 700m, 643w, 625w, 613w, 575w, 544w. 1H-NMR: 3.33 (s, MeO);
6.88 – 6.93 (m, 4 arom. H); 7.06 (d, 3J ¼ 8.7, 1 arom. H); 7.17 – 7.19 (m, 3 arom. H); 7.60 (d, 3J ¼ 8.7, 1 arom.
H); 7.91 – 7.94 (m, 2 arom. H); 11.03 (s, OH). 13C-NMR: 51.2 (MeO); 113.6 (CCOOMe); 118.0 (arom.
CH); 120.1 (arom. C); 122.8 (2 arom. CH); 125.1 (2 arom. CH); 126.3 (arom. CH); 126.4 (2 arom. CH);
127.0 (2 arom. CH); 139.3 (arom. C); 141.1 (arom. CH); 144.1, 148.2, 148.5 (arom. C); 161.9 (COH);
169.7 (CO). GC/EI-MS (70 eV): 381 (39, Mþ), 349 (100), 319 (24), 303 (7), 274 (7), 247 (10), 202 (6),
171 (23), 139 (13). HR-EI-MS: 381.0669 (Mþ, C20H15O5NSþ; calc. 381.0665).
Methyl 3-Hydroxy-4-methyl-6-[(4-nitrophenyl)sulfanyl]-1,1’-biphenyl-2-carboxylate (5j). GP 3 with
3d (0.494 g, 1.5 mmol) and 4b (0.453 g, 1.65 mmol): 5j (0.285 g, 48%). Crystalline solid. M.p. 124 – 1268.
IR (neat): 3101w, 3088w, 3059w, 3021w, 2952w, 2922w, 2903w, 2855w, 1723w, 1713w, 1668m, 1592m,
1572m, 1499m, 1475m, 1439m, 1398m, 1326s, 1243s, 1196s, 1158s, 1108m, 1018m, 945m, 884m, 846s, 810s,
743s, 678s, 624m, 542m. 1H-NMR: 2.20 (s, Me); 3.26 (s, MeO); 6.81 – 6.87 (m, 4 arom. H); 7.08 – 7.13 (m, 3
arom. H); 7.43 (s, 1 arom. H); 7.83 – 7.88 (m, 2 arom. H); 11.20 (s, OH). 13C-NMR: 14.8 (Me); 51.1
(MeO); 112.7 (CCOOMe); 118.8 (arom. C); 122.8 (2 arom. CH); 124.9 (2 arom. CH); 126.0 (arom. CH);
126.2 (2 arom. CH); 127.1 (2 arom. CH); 127.5, 139.5 (arom. C); 141.5 (arom. CH); 144.0, 146.0, 148.7
(arom. C); 160.5 (COH); 170.2 (CO). GC/EI-MS (70 eV): 395 (27, Mþ), 363 (100), 333 (25), 316 (5), 219
(38), 209 (21), 184 (9), 152 (10), 129 (10), 93 (6), 73 (12). HR-EI-MS: 395.0754 (Mþ, C21H17NO5Sþ; calc.
395.0755). The structure of 5j was secured by an X-ray crystal-structure analysis (cf. Fig.)1)
Methyl 4-Ethyl-3-hydroxy-6-[(4-nitrophenyl)sulfanyl]-1-1’-biphenyl-2-carboxylate (5k). GP 3 with
3d (0.494 g, 1.5 mmol) and 4c (0.476 g, 1.65 mmol): 5k (0.246 g, 40%). Yellowish oil. IR (neat): 3107w,
3089w, 3062w, 3025w, 2961w, 2929w, 2851w, 1659m, 1593m, 1575m, 1556w, 1504m, 1476m, 1434m, 1407m,
1353m, 1332s, 1260m, 1197m, 1109m, 1016m, 926m, 853m, 787m, 740s, 699s, 650m, 625m, 565m, 542m.
1H-NMR: 1.19 (t, 3J ¼ 7.5, MeCH2); 2.68 (q, 3J ¼ 7.4, MeCH2); 3.32 (s, MeO); 6.86 – 6.93 (m, 4 arom. H);
1
)
CCDC-769128 contains all crystallographic details of this publication which are available free of
charge at www.ccdc.cam.ac.uk/conts/retrieving.html or can be ordered from the following address:
Cambridge Crystallographic Data Centre, 12 Union Road, GB-Cambridge CB21EZ; fax:
(þ44)1223-336-033; or deposit@ccdc.cam.ac.uk.

Helvetica Chimica Acta – Vol. 93 (2010)
1619
7.13 – 7.19 (m, 3 arom. H); 7.48 (s, 1 arom. H); 7.88 – 7.94 (m, 2 arom. H); 11.25 (s, OH). 13C-NMR: 12.5
(Me); 21.9 (CH2); 51.1 (MeO); 113.0 (CCOOMe); 119.0 (arom. C); 122.8 (2 arom. CH); 124.9 (2 arom.
CH); 126.1 (arom. CH); 126.2 (2 arom. CH); 127.1 (2 arom. CH); 133.2, 139.6 (arom. C); 140.0 (arom.
CH); 143.9, 146.0, 148.7 (arom. C); 160.1 (COH); 170.2 (CO). GC/EI-MS (70 eV): 409 (30, Mþ), 377
(100), 347 (49), 254 (15), 223 (70), 205 (31), 184 (12), 165 (26), 129 (12), 93 (12), 69 (8). HR-EI-MS:
409.0988 (Mþ, C22H19NO5Sþ; calc. 409.0978).
Methyl 3-Hydroxy-6-[(4-nitrophenyl)sulfanyl]-4-pentyl-1,1’-biphenyl-2-carboxylate (5l). GP 3 with
3d (0.494 g, 1.5 mmol) and 4d (0.546 g, 1.65 mmol): 5l (0.325 g, 48%). Yellowish oil. IR (neat): 3058w,
3024w, 2952w, 2926w, 2857w, 1746w, 1711w, 1662m, 1632w, 1594m, 1577m, 1512m, 1438m, 1409m, 1333s,
1296m, 1233m, 1198m, 1162m, 1109m, 1011m, 952w, 852m, 812m, 750m, 699m, 681m, 626w, 543w.
1H-NMR: 0.83 (t, 3J ¼ 7.1, Me(CH2)4); 1.26 – 1.30 (m, 2 CH2); 1.56 – 1.61 (m, CH2); 2.63 (t, 3J ¼ 7.5,
Me(CH2)3CH2); 3.31 (s, MeO); 6.86 – 6.93 (m, 4 arom. H); 7.15 – 7.19 (m, 3 arom. H); 7.46 (s, 1 arom. H);
7.89 – 7.92 (m, 2 arom. H); 11.23 (s, OH). 13C-NMR: 13.0 (Me); 21.5, 27.8, 28.7, 30.6 (CH2); 51.1 (MeO);
113.0 (CCOOMe); 118.9 (arom. C); 122.8 (2 arom. CH); 124.9 (2 arom. CH); 126.1 (arom. CH); 126.3
(2 arom. CH); 127.1 (2 arom. CH); 132.0, 139.6 (arom. C); 140.8 (arom. CH); 143.9, 146.0, 148.8 (arom.
C); 160.1 (COH); 170.2 (CO). GC/EI-MS (70 eV): 451 (64, Mþ), 419 (70), 402 (10), 389 (40), 363 (11),
346 (46), 265 (25), 240 (22), 209 (100), 152 (11). HR-EI-MS: 451.1457 (Mþ, C25H25NO5Sþ; calc.
451.1448).
Methyl 4-Hexyl-3-hydroxy-6-[(4-nitrophenyl)sulfanyl]-1,1’-biphenyl-2-carboxylate (5m). GP 3 with
3d (0.494 g, 1.5 mmol) and 3e (0.569 g, 1.65 mmol): 5m (0.293 g, 42%). Yellowish oil. IR (neat): 3059w,
3024w, 2953w, 2926m, 2855w, 2258w, 1932w, 1664m, 1594w, 1578m, 1514w, 1438m, 1409m, 1333s, 1234m,
1198m, 1161m, 1110w, 1085m, 1010w, 907m, 851m, 839m, 768m, 729s, 698s, 681m, 648m, 626w, 544w.
1H-NMR: 0.71 (t, 3J ¼ 6.8, Me(CH2)5); 1.08 – 1.19 (m, 3 CH2); 1.40 – 1.50 (m, CH2); 2.53 (t, 3J ¼ 7.5,
Me(CH2)4CH2); 3.21 (s, MeO); 6.76 – 6.83 (m, 4 arom. H); 7.03 – 7.08 (m, 3 arom. H); 7.36 (s, 1 arom. H);
7.79 – 7.83 (m, 2 arom. H); 11.13 (s, OH). 13C-NMR: 15.3 (Me); 23.8, 30.3, 30.4, 31.0, 32.8 (CH2); 53.3
(MeO); 115.2 (CCOOMe); 121.1 (arom. C); 125.0 (2 arom. CH); 127.1 (2 arom. CH); 128.3 (arom. CH);
128.5 (2 arom. CH); 129.3 (2 arom. CH); 134.2, 141.8 (arom. C); 143.0 (arom. CH); 146.1, 148.2, 151.0
(arom. C); 162.3 (COH); 172.4 (CO). GC/EI-MS (70 eV): 465 (100, Mþ), 403 (24), 346 (80), 316 (9), 279
(22), 209 (96), 152 (11). HR-EI-MS: 465.1679 (Mþ, C26H27NO5Sþ; calc. 465.1683).
Methyl 3-Hydroxy-6-[(4-nitrophenyl)sulfanyl]-4-octyl-1,1’-biphenyl-2-carboxylate (5n). GP 3 with
3d (0.494 g, 1.5 mmol) and 4f (0.615 g, 1.65 mmol): 4n (0.333 g, 45%). Yellowish oil. IR (neat): 2953m,
2923m, 2853m, 1746w, 1714w, 1664m, 1627w, 1595w, 1579w, 1516m, 1438m, 1408m, 1334s, 1233m, 1198m,
1
3
1162m, 1085m, 1011m, 909w, 852m, 814m, 741m, 699m, 681m, 626w, 543w. H-NMR: 0.81 (t, J ¼ 6.9,
Me(CH2)7); 1.17 – 1.22 (m, 5 CH2); 1.53 – 1.60 (m, CH2); 2.63 (t, 3J ¼ 7.5, Me(CH2)6CH2); 3.31 (s, MeO);
6.86 – 6.93 (m, 3 arom. H); 7.15 – 7.19 (m, 4 arom. H); 7.46 (s, 1 arom. H); 7.90 – 7.93 (m, 2 arom. H); 11.23
(s, OH). 13C-NMR: 13.1 (Me); 21.6, 28.1, 28.3, 28.4, 28.6, 28.7, 30.8 (CH2); 51.1 (MeO); 113.0
(CCOOMe); 118.8 (arom. C); 122.8 (2 arom. CH); 124.9 (2 arom. CH); 126.1 (arom. CH); 126.3 (2 arom.
CH); 127.1 (2 arom. CH); 132.0, 139.6 (arom. C); 140.8 (arom. CH); 143.9, 146.0, 148.8 (arom. C); 160.1
(COH); 170.2 (CO). GC/EI-MS (70 eV): 493 (6, Mþ), 463 (90), 431 (100), 405 (10), 374 (12), 333 (16),
307 (23), 253 (16), 240 (89), 221 (23), 209 (98), 184 (22), 152 (35), 124 (55), 105 (22), 93 (56), 55 (51).
HR-EI-MS: 493.1849 (Mþ, C28H31NO5Sþ; calc. 493.1850).
Methyl 4-Decyl-3-hydroxy-6-[(4-nitrophenyl)sulfanyl]-1,1’-biphenyl-2-carboxylate (5o). GP 3 with
3d (0.494 g, 1.5 mmol) and 4g (0.661 g, 1.65 mmol): 5o (0.391 g, 50%). Yellowish oil. IR (neat): 2952w,
2922m, 2852m, 1934w, 1748w, 1704w, 1664m, 1594w, 1578m, 1515m, 1438m, 1408m, 1334s, 1233m, 1198m,
1
3
1163m, 1085m, 1010m, 909w, 851m, 814m, 741m, 698m, 681m, 626w, 543w. H-NMR: 0.70 (t, J ¼ 6.8,
Me(CH2)9); 1.07 – 1.11 (m, 7 CH2); 1.40 – 1.50 (m, CH2); 2.53 (t, 3J ¼ 7.4, Me(CH2)8CH2); 3.21 (s, MeO);
6.76 – 6.82 (m, 4 arom. H); 7.05 – 7.09 (m, 3 arom. H); 7.36 (s, 1 arom. H); 7.79 – 7.82 (m, 2 arom. H); 11.12
(s, OH). 13C-NMR: 15.3 (Me); 23.9, 30.3, 30.5, 30.6, 30.7, 30.8, 30.9, 31.0, 33.1 (CH2); 53.3 (MeO); 115.2
(CCOOMe); 121.0 (arom. C); 125.0 (2 arom. CH); 127.1 (2 arom. CH); 128.3 (arom. CH); 128.5 (2 arom.
CH); 129.3 (2 arom. CH); 134.2, 141.8 (arom. C); 143.0 (arom. CH); 146.1, 148.2, 151.0 (arom. C); 162.3
(COH); 172.4 (CO). GC/EI-MS (70 eV): 521 (97, Mþ), 489 (50), 472 (11), 459 (22), 404 (13), 362 (29),
346 (44), 335 (19), 240 (17), 209 (100), 180 (7), 152 (9), 116 (21), 101 (9). HR-EI-MS: 521.2303 (Mþ,
C30H35NO5Sþ; calc. 521.2309).

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Helvetica Chimica Acta – Vol. 93 (2010)
Methyl 6-(Benzylsulfanyl)-4-ethyl-3-hydroxy-1,1’-biphenyl-2-carboxylate (5p). GP 3 with 3e
(0.448 g, 1.5 mmol) and 4c (0.476 g, 1.65 mmol): 5p (0.267 g, 47%). Yellowish oil. IR (neat): 3060w,
3027w, 2963w, 2932w, 2873w, 1935w, 1728w, 1662m, 1597m, 1494w, 1435m, 1337m, 1276m, 1230m, 1196m,
1160m, 1069m, 1013m, 969m, 843m, 748m, 696s, 646m, 629m, 562m. 1H-NMR: 1.10 (t, 3J ¼ 7.5, MeCH2);
1.48 (s, CH2); 2.57 (q, 3J ¼ 7.3, MeCH2); 3.28 (s, MeO); 6.93 – 6.97 (m, 4 arom. H); 7.18 – 7.23 (m, 7 arom.
H); 10.85 (s, OH). 13C-NMR: 12.5 (Me); 21.8, 39.2 (CH2); 50.8 (MeO); 112.1 (CCOOMe); 125.7, 125.9
(arom. CH); 126.2 (2 arom. CH); 126.6, 127.1 (arom. C); 127.3 (2 arom. CH); 127.5 (arom. CH); 127.9 (2
arom. CH); 128.4 (arom. CH); 136.4, 136.5 (arom. C); 137.0 (arom. CH); 140.1 (arom. C); 157.7 (COH);
170.5 (CO). GC/EI-MS (70 eV): 378 (2, Mþ), 346 (5), 255 (8), 120 (50), 105 (100), 91 (94), 77 (51), 65
(22), 51 (18). HR-EI-MS: 378.1283 (Mþ, C23H22O3Sþ; calc. 378.1284).
Methyl 4-Ethyl-3-hydroxy-6-[(naphthalen-2-yl)sulfanyl]-1,1’-biphenyl-2-carboxylate (5q). GP 3 with
3f (0.502 g, 1.5 mmol) and 4c (0.476 g, 1.65 mmol): 5q (0.324 g, 52%). Yellowish oil. IR (neat): 3052w,
3024w, 2963w, 2950w, 2932w, 2873w, 1932w, 1698w, 1660s, 1591m, 1499w, 1435m, 1337m, 1290m, 1229s,
1
3
1195m, 1161m, 1063m, 967m, 847m, 743s, 697s, 628m, 600m, 529m. H-NMR: 1.00 (t, J ¼ 7.5, MeCH2);
2.47 (q, 3J ¼ 7.5, MeCH2); 3.20 (s, MeO); 6.89 – 6.99 (m, 3 arom. H); 7.07 – 7.10 (m, 3 arom. H); 7.22 – 7.28
(m, 4 arom. H); 7.45 – 7.49 (m, 2 arom. H); 7.55 – 7.58 (m, 1 arom. H); 10.93 (s, OH). 13C-NMR: 14.8
(Me); 24.2 (CH2); 53.1 (MeO); 114.6 (CCOOMe); 125.5 (arom. C); 126.9, 127.7, 128.1, 128.4 (arom.
CH); 128.5 (2 arom. CH); 128.8, 128.9, 129.4, 129.6, (arom. CH); 129.8 (2 arom. CH); 133.0, 134.6, 134.9,
136.7 (arom. C); 140.2 (arom. CH); 142.2, 145.6 (arom. C); 160.8 (COH); 172.7 (CO). GC/EI-MS
(70 eV): 414 (37, Mþ), 382 (100), 254 (35), 223 (40), 160 (31), 128 (47), 77 (9), 63 (7), 44 (8). HR-EI-
MS: 414.1286 (Mþ, C26H22O3Sþ; calc. 414.1284).
Financial support from the State of Mecklenburg-Vorpommern (scholarship for M. S. and to M. H.) is
gratefully acknowledged.
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Received November 9, 2009