A facile synthesis of tetraarylethenes via cross McMurry coupling between diaryl ketones

Article abstract of DOI:10.1055/s-2007-965906

The one-pot, cross McMurry coupling between two different diaryl ketones gave structurally varied tetraarylethenes in 59-80% isolated yields. This synthetic protocol is more convenient and effective compared to previously reported procedures. Georg Thieme Verlag Stuttgart.

Full text of DOI:10.1055/s-2007-965906

PAPER
713
A Facile Synthesis of Tetraarylethenes via Cross McMurry Coupling between
Diaryl Ketones
A
F
acile Synthesis
i
of
T
etr
n
aarylethenes
-
via Cro
F
ss McMurry
C
a
oupling be
n
tween Diary
g
l
Ketones Duan,* Jing Zeng, Jia-Wei Lü, Zhan-Bin Zhang
Department of Chemistry, Beijing Normal University, Beijing, 100875, P. R. of China
Fax +86(01)58802235; E-mail: xinfangduan@vip.163.com
Received 27 October 2006; revised 24 November 2006
ucts.12 So far the few successful cross McMurry reactions
Abstract: The one-pot, cross McMurry coupling between two dif-
ferent diaryl ketones gave structurally varied tetraarylethenes in 59–
80% isolated yields. This synthetic protocol is more convenient and
effective compared to previously reported procedures
are mainly limited to: (a) two carbonyl compounds with
significant molecular mass difference;13 and (b) diaryl ke-
tones with aryl or alkyl ketones or aldehydes.13,14
Key words: cross McMurry reaction, tetraphenylethene, diaryl ke- Initially we studied the cross McMurry coupling of diphe-
tone, McMurry reaction, low-valent titanium
nyl ketone (benzophenone, 1a) with 4-methylphenyl phe-
nyl ketone (1b) and bis[4-(morpholin-4-yl)phenyl] ketone
(1c) (Table 1, entries 1, 2). The reactions were performed
with the titanium(IV) chloride/zinc/pyridine system under
standard conditions,15 and the ketones were charged in
equimolar amounts. It was observed that the coupling of
1a with 1b (Table 1, entry 1) resulted in a roughly statis-
tical, inseparable, mixture of three possible products 2a,
2b, and 3b. By contrast, the coupling of 1a with 1c
(Table 1, entry 2) resulted in selective cross coupling to
give 2c in 56% isolated yield. We postulate that the strong
affinity of the morpholin-4-yl group to the low-valent ti-
tanium surface played an important role with regards to
moderating selectivity.
Tetraphenylethene and its ring-substituted analogues dis-
play several interesting photophysical and redox proper-
ties by virtue of the fact that they contain both aromatic
and olefinic centers.1 They enjoy widespread, or potential,
use in various reactions such as reduction, oxidation, and
photocyclization;2 in materials science they are used as
columnar liquid crystals3 or molecular switches.4 Recent-
ly tetrakis(2-hydroxyphenyl)ethene and its derivatives
were investigated as an alternative to the calix[4]arene
ligand system.5 Noteworthy is the report that tetra(4-bro-
mophenyl)ethene forms chiral inclusion crystals with
achiral guests such as acetone and benzene, which pro-
vides a new strategy for the preparation of chiral crystals.6
Although there is an extensive need for such molecules,
the reported procedures are mainly limited to the prepara-
tion of symmetrical tetraarylethenes via homocoupling
reactions of diaryldiazomethanes,5,7 diaryldichloro-
methanes,8 diaryl thioketones,9 and diaryl ketones.3,4a,10
The synthesis of unsymmetrically substituted analogues is
generally achieved using palladium- or nickel-catalyzed
cross-coupling reactions.11
This is exemplified by comparing two cross-coupling re-
actions: 1a with 1b (Table 1, entry 1) and 1a with 4-(mor-
pholin-4-ylmethyl)phenyl phenyl ketone (1d) (Table 1,
entry 3). Obviously apart from a morpholin-4-yl group,
the reduction potential or electronic density of the carbo-
nyl moiety of 1d and 1b appears quite similar. Optimiza-
tion of the reaction parameters (mole ratio of 1a to 1b–d,
source and number of equivalents of the low-valent-titani-
um reagent, temperature) was then performed on the cou-
pling of 1a with 1c. The results are summarized in
Table 1, entries 4–16.
We report herein a novel synthetic protocol for the prepa-
ration of tetraarylethenes, especially for unsymmetrically
substituted analogues, using cross McMurry coupling be-
tween two different diaryl ketones. Because the reagents
are readily available and the operations are simple, this
synthesis proves to be more convenient and effective
compared to those previously reported.
It was observed that an excess of 1c relative to 1a im-
proved the yields of the cross coupling slightly (Table 1,
entries 4, 5). We found that the homocoupling of 1c (to
give 3c) went more slowly than that of 1a (to give 2a). Us-
ing 1c in excess slowed the entire reaction significantly,
alternatively using an excess of 1a resulted in an obvious
increase in the yield of its cross-coupling product
(Table 1, compare entries 4, 5 vs entries 6, 7). The influ-
ence of the amount of low-valent-titanium reagent indi-
cated that 4–8 equivalents of titanium were sufficient for
selective cross coupling. However, when the number of
equivalents of the low-valent-titanium reagent was raised
to 15:1, the mixed coupling gave a roughly statistical mix-
ture of three products (Table 1, entries 8–11). Lowering
the reaction temperature decelerated the coupling reac-
tion, but did not enhance the selectivity of the cross cou-
pling (Table 1, entries 12, 13). Two other types of low-
Although the preparation of tetraarylethenes via the
McMurry homocoupling of diaryl ketones has been docu-
mented,3,4a,10 the synthesis by the cross coupling of two
different diaryl ketones still remains a challenge. This re-
sults from the general belief that the cross McMurry cou-
pling between two different carbonyl compounds will
generate a roughly statistical mixture of the possible prod-
SYNTHESIS 2007, No. 5, pp 0713–0718
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x
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x
x
.2
0
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Advanced online publication: 25.01.2007
DOI: 10.1055/s-2007-965906; Art ID: Z22006SS
© Georg Thieme Verlag Stuttgart · New York

714
X.-F. Duan et al.
PAPER
Table 1 Cross McMurry Coupling of Diphenyl Ketone (1a) with Diaryl Ketones 1b–d and Optimization of the Reaction Conditions
Ar1
Ar2
Ph
Ph
Ph
Ph
Ph
Ph
Ar2
[Ti]
+
+
O
O
+
Ar2
Ar1
Ph
Ph
Ar1
Ar2
Ar2
2b–d
3b–d
2a
1b–d
1a
1–3 b: Ar1 = Ph, Ar2 = 4-Tol
c Ar1 = Ar2 = 4-(morpholin-4-yl)phenyl
d Ar1 = Ph, Ar2 = 4-(morpholin-4-ylmethyl)phenyl
Entry
Ketone
[Ti]a (equiv)
Mole ratiob
Products 2,3
Products 2 and 3, yield (%)
2a
28c
17
14
13
6
2b–d
44c
56
61
62
64.5
73
71
64
70
72
36
59
62
56
51
–
3b–d
28c
17
9
1
2
1b
1c
1d
1c
1c
1c
1c
1c
1c
1c
1c
1c
1c
1c
1c
1c
A (5)
A (5)
A (5)
A (5)
A (5)
A (5)
A (5)
A (2)
A (4)
A (8)
A (15)
A (5)
A (5)
B (5)
B (5)
C (15)
1:1
b
c
d
c
c
c
c
c
c
c
c
c
c
c
c
–
1:1
3
1:1
4d
5d
6
1:1.2
1:1.5
1.2:1
1.5:1
1.2:1
1.2:1
1.2:1
1.2:1
1.2:1
1.2:1
1.2:1
1.2:1
1.2:1
12
12
8
13
13
16
14
8
7
6
8
11
8
9
10
11
12e
13f
14g
15h
16
9
28
14
13
19
20
70
27
12
11
16
19
–
a Low-valent-titanium reagent: A, TiCl4, Zn, py, THF; B, TiCl4, Zn, KCl, THF; C, Ti powder, TMSCl, THF; unless otherwise stated, reflux, 30 h.
b Mole ratio of 1a to 1b–d.
c The yields were determined by GC analysis.
d The coupling was complete in ca. 45 h.
e Conditions: r.t., 67 h.
f Conditions: 40–45 °C, 50 h.
g Conditions: r.t., 17 h.
h Conditions: reflux, 7 h.
valent-titanium reagent10b,16 were also tested in the cross Table 2. It was observed that a series of substituents con-
coupling. It was found that the coupling using a titani- taining nitrogen or oxygen atom(s) could enhance the se-
um(IV) chloride/zinc/potassium chloride system occurred lectivity of the cross coupling. The position of these
faster with lower yields of the cross-coupling product 2b substituents on aromatic rings did not affect the outcome
than those using the titanium(IV) chloride/zinc/pyridine of the cross coupling substantially (Table 2, entries 1–3, 7,
system (Table 1, entries 14, 15). In our hands, only the ho- 8, 10, 11). Diaryl ketones with these cross-coupling-en-
mocoupling of 1a to give 2a occurred using the titanium hancing-substituents could also cross couple with 3-bro-
powder/chlorotrimethylsilane system. (Table 1, entry 16). mophenyl or 4-tolyl ketones selectively (Table 2, entries
5, 9, 12). It should be noted that although lacking such
Under the optimized reaction conditions a variety of tet-
substituents, 4-fluorophenyl 2-furyl ketone (4m) still cou-
raarylethenes 5 were conveniently prepared in 59–80%
pled selectively with diphenyl ketone (1a) (Table 2, entry
isolated yields through the cross coupling of two different
diaryl ketones 1 and 4. The results are summarized in
Synthesis 2007, No. 5, 713–718 © Thieme Stuttgart · New York

PAPER
A Facile Synthesis of Tetraarylethenes via Cross McMurry Coupling between Diaryl Ketones
715
Table 2 Preparations of Tetraarylethenes via the Cross McMurry Coupling of Two Different Diaryl Ketonesa
Ar1
Ar2
Ar3
Ar4
Ar1
Ar2
Ar3
Ar4
TiCl4-Zn-Py
THF
O
O
+
5a–n
4a–n
1a: Ar1 = Ar2 = Ph
1c: Ar1 = Ar2 = 4-(morpholin-4-yl)phenyl
1e: Ar1 = Ar2 = 4-HOC6H4
1f: Ar1 = Ph, Ar2 = 4-H2NC6H4
Entry
Product
5a
Ar1
Ar2
Ph
Ph
Ph
Ph
Ar3
Ar4
Yield (%)
1
2
3b
4
5
6
7
Ph
Ph
4-HOC6H4
3-HOC6H4
2-HOC6H4
4-HOC6H4
4-BrC6H4
4-MeOC6H4
66
62
64
69
69
59
62
5b
Ph
Ph
5c
Ph
Ph
5d
Ph
4-HOC6H4
Ph
5e
4-HOC6H4
4-HOC6H4
5f
Ph
Ph
Ph
Ph
4-MeOC6H4
Ph
5g
4-(morpholin-4-yl)-
phenyl
8
9
5h
5i
Ph
Ph
Ph
Ph
2-(morpholin-4-yl)-
phenyl
61
77
4-(morpholin-4-yl)-
phenyl
4-(morpholin-4-yl)-
phenyl
4-BrC6H4
10
11
12
13
14
5j
Ph
Ph
Ph
Ph
Ph
Ph
Ph
4-H2NC6H4
2-H2NC6H4
4-Tol
80
72
76
70
65
5k
5l
Ph
Ph
2-H2NC6H4
4-Tol
4-FC6H4
5m
5n
Ph
Ph
2-furyl
4-(morpholin-4-yl)-
phenyl
2-thienyl
a The ketones were charged with the mole ratios of 1.2 to 1 (1 to 4); 5 equiv of low-valent-titanium reagent were used, reflux, 20–30 h.
b The coupling was performed using low-valent-titanium reagent (2 equiv), reflux.
13). In contrast, the selective cross coupling of 2-thienyl
ketone was achieved in the presence of a morpholin-4-yl
group (Table 2, entry 14).
N
O
(a)
+
O
O
During research into the photophysical properties of tet-
raarylethenes, we needed a series of tetraarylethene-based
building blocks, such as 1-(4-bromophenyl)-1,2,2-triphe-
nylethene and 1-[4-(chloromethyl)phenyl]-1,2,2-triphe-
nylethene (6), which can be easily linked to a target
molecule. These compounds can be conveniently pre-
pared by means of the above-mentioned synthetic proto-
col. For example, 1-(4-bromophenyl)-1,2,2-triphenyl-
ethene was prepared in two steps in 61% total yield by
cross McMurry coupling of 1 with 4j to give 5j (Table 2,
entry 10); (b) diazotization of 5j followed by bromination
gave the desired product. In contrast, its reported prepara-
tion was as a side product in only 5% yield.17 1-[4-(Chloro-
methyl)phenyl]-1,2,2-triphenylethene (6) was first
synthesized as illustrated in Scheme 1.
1d
1a
N
Cl
O
(b)
6
2d
Scheme 1 Synthesis of 1-[4-(chloromethyl)phenyl]-1,2,2-triphenyl-
ethene. Reagents and conditions: (a) TiCl4, Zn, py, THF, reflux, 30 h,
61%; (b) ClCO2Et, MeCN, reflux, 7 h, 87%.
Synthesis 2007, No. 5, 713–718 © Thieme Stuttgart · New York

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X.-F. Duan et al.
PAPER
13C NMR (CDCl3): d = 53.5, 63.2, 66.9, 126.3, 126.4, 127.6, 128.5,
131.2, 131.3, 135.6, 140.7, 140.9, 142.7, 143.6, 143.7, 143.8.
In conclusion, we report a novel synthetic approach to tet-
raarylethenes. Its advantages over previously reported
procedures are: (a) the reagents are readily available; (b) MS (EI): m/z (%) = 431 (M+, 75), 345 (45), 252 (26), 86 (41), 49
(100).
the two different diaryl ketones are charged in nearly
equimolar amounts (1.2:1); (c) the operations are simple
and performed in one flask; and (d) the yields are accept-
able. Importantly, we also provide a new procedure for
cross McMurry coupling. The investigation of the mecha-
nism of these selective cross-coupling reactions and the
general cross McMurry coupling between two different
carbonyl compounds are under way in our laboratory.
Anal. Calcd for C31H19N: C, 86.27; H, 6.77; N, 3.25. Found: C,
85.99; H, 6.77; N, 3.25.
1-(4-Hydroxyphenyl)-1,2,2-triphenylethene (5a)18
Colorless solid; yield: 66%; mp 215–216 °C (Lit.18 215–217 °C);
Analytical data were identical with those reported.
1-(3-Hydroxyphenyl)-1,2,2-triphenylethene (5b)
Colorless solid; yield: 62%; mp 228.9–229.5 °C.
IR (KBr): 3519.9, 3050.5, 3017.1, 1591.7, 1441.9, 1180.3, 745.4,
699.4, 639.5 cm–1.
Melting points were obtained on a RY-1 microscopical instrument
and were uncorrected. NMR spectra were recorded with an Ad-
vance 500 Bruker (500 MHz) spectrometer. Elemental analyses
were performed with an Elementar Vario EL analyzer. IR spectra
were recorded with a Vaatar 360 FT-IR spectrophotometer. MS
spectra were recorded on a Trace MS 2000 spectrometer. GC was
performed with a Varian CP-3800 gas chromatography analyzer.
All reagents and solvents used for the McMurry reactions were
freshly dried before use. Zinc powder was freshly activated by aq
1% HCl, washed with distilled H2O, abs EtOH, and Et2O, and then
dried under vacuum. All glassware was oven dried (120 °C) and
cooled under a stream of argon gas.
1H NMR (CDCl3): d = 4.47 (br, 1 H), 6.52 (s, 1 H), 6.60–6.65 (m, 2
H), 6.99 (m, 1 H), 7.03–7.08 (m, 6 H), 7.11–7.13 (m, 9 H).
13C NMR (CDCl3): d = 113.6, 118.1, 124.1, 126.5, 126.5, 127.7,
128.8, 131.1, 131.2, 131.3, 140.4, 141.2, 143.5, 143.6, 145.3, 154.9.
MS (EI): m/z (%) = 348 (M+, 100), 333 (9), 270 (17), 252 (27), 165
(23).
Anal. Calcd for C26H20O: C, 89.62; H, 5.79. Found: C, 89.33; H,
5.72.
1-(2-Hydroxyphenyl)-1,2,2-triphenylethene (5c)
Colorless solid; yield: 64%; mp 201.4–202.7 °C.
Diaryl Ketones 2b–d and 5a–n; General Procedure
Under an argon atmosphere, a 4-necked flask equipped with a mag-
netic stirrer was charged with Zn powder (1.6 g, 24 mmol) and THF
(40 mL). The mixture was cooled to –5 °C to 0 °C, and TiCl4 (1.3
mL, 12 mmol) was added slowly by syringe with the temperature
maintained under 10 °C. The suspended mixture was warmed to r.t.
and stirred for 0.5 h, then heated to reflux for 2.5 h. The mixture was
again cooled to –5 °C to 0 °C, charged with pyridine (0.5 mL, 6
mmol), and stirred for 10 min. The soln of two diaryl ketones [in
1:1.5 to 1.2:1 mole ratio (as illustrated in Tables 1 and 2)], 2.4 mmol
(or as illustrated in Tables 1 and 2)] in THF (15 mL) was added
slowly. When the addition was complete, the mixture was heated to
reflux until the carbonyl compounds were consumed (monitored by
TLC). The reaction was quenched by addition of 10% aq K2CO3 and
extracted with CH2Cl2. The products were isolated and purified by
flash chromatography.
IR (KBr): 3527.3, 3014.8, 1589.8, 1488.6, 1442.4, 1176.7, 873,
749.8, 699.2, 624.8 cm–1.
1H NMR (CDCl3): d = 5.09 (br, 1 H), 6.75–6.78 (m, 2 H), 7.01 (d,
J = 8.5 Hz, 1 H), 7.04–7.12 (m, 6 H), 7.14–7.18 (m, 10 H).
MS (EI): m/z (%) = 348 (M+, 97), 270 (57), 165 (100), 105 (62), 77
(56).
Anal. Calcd for C26H20O: C, 89.62; H, 5.79. Found: C, 89.79, H,
5.56.
1,1-Bis(4-hydroxyphenyl)-2,2-diphenylethene (5d)
Colorless solid; yield: 69%; mp 222.9–223.7 °C.
IR (KBr): 3404.2, 1608.2, 1508.4, 1442.8, 1254.9, 1170.7, 834.6,
765.8, 700.6, 592.4, 570.0 cm–1.
1H NMR (CDCl3): d = 4.58 (s, 2 H), 6.59 (d, J = 8.44 Hz, 4 H), 6.92
(d, J = 8.43 Hz. 4 H), 7.04 (d, J = 7.32 Hz, 4 H), 7.12 (t, J = 7.03 Hz,
6 H).
1,1-Bis(4-morpholin-4-ylphenyl)-2,2-diphenylethene (2c)
Yellow solid; mp 205.1–206.2 °C.
IR (KBr): 3044.5, 2954.4, 1606.5, 1513.3, 1230.6, 1122.9, 925.5,
701.7 cm–1.
13C NMR (CDCl3): d = 114.4, 125.9, 127.6, 131.1, 132.4, 134.9,
144.6, 156.1.
1H NMR (CDCl3): d = 3.14 (br s, 8 H), 3.86 (br s, 8 H), 6.91 (s, 4
H), 6.95 (m, 4 H), 7.04–7.05 (m, 4 H), 7.07–7.14 (m, 6 H).
MS (EI): m/z (%) = 364 (M+, 100), 270 (15), 165 (14).
13C NMR (CDCl3): d = 48.9, 66.9, 114.3, 125.9, 127.6, 131.4,
132.4, 135.5, 138.6, 140.3, 144.6, 149.3.
Anal. Calcd for C26H20O2: C, 85.69; H, 5.53. Found: C, 85.39; H,
5.80.
MS (EI): m/z (%) = 503 (M+, 100), 444 (36), 386 (26), 252 (30), 165
(17).
1-(4-Bromophenyl)-2,2-bis(4-hydroxyphenyl)-1-phenylethene
(5e)
Colorless solid; yield: 69%; mp 234.5–235.0 °C.
Anal. Calcd for C34H34N2O2: C, 81.24; H, 6.82; N, 5.57. Found: C,
80.93; H, 7.24; N, 5.58.
IR (KBr): 3316.3, 3019.1, 1605.5, 1591.6, 1506.5, 1237.9, 838.35,
703.0 cm–1.
1-[4-(Morpholin-4-ylmethyl)phenyl]-1,2,2-triphenylethene (2d)
Colorless solid; yield: 61%; mp 152.1–153.0 °C.
1H NMR (CDCl3): d = 4.64 (br, 2 H), 6.59–6.78 (m, 4 H), 6.78 (m,
1 H), 6.89–6.92 (m, 5 H), 7.05–7.25 (m, 7 H).
IR (KBr): 2922.4, 2852.7, 1597.7, 1491.6, 1443.2, 1116.9, 696.5
cm–1.
MS (EI): m/z (%) = 444 (M+, 100), 364 (32), 252 (10), 165 (26), 107
(40).
1H NMR (CDCl3): d = 2.42 (s, 4 H), 3.45 (s, 2 H), 3.73 (s, 4 H),
6.99–7.12 (m, 19 H).
Anal. Calcd for C26H19BrO2: C, 70.44; H, 4.32. Found: C, 70.12; H,
4.61.
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A Facile Synthesis of Tetraarylethenes via Cross McMurry Coupling between Diaryl Ketones
717
1-(4-Methoxyphenyl)-1,2,2-triphenylethene (5f)
Colorless solid; yield: 59%; mp 140–141.5 °C (Lit.19 139–141 °C);
Analytical data (IR, 1H NMR) were identical with those reported.
Anal. Calcd for C26H21N: C, 89.88; H, 6.09; N, 4.03. Found: C,
89.75; H, 5.75; N, 3.93.
1-(4-Aminophenyl)-2,2-bis(4-methylphenyl)-1-phenylethene
(5l)
Yellow solid; yield: 76%; mp 173.3–173.9 °C.
1-(4-Morpholin-4-ylphenyl)-1,2,2-triphenylethene (5g)
Yellow solid; yield: 62%; mp 177.4–178.8 °C.
IR (KBr): 2931.1, 2857.0, 1599.6, 1519.3, 1448.4 1231.6, 1113.3,
926.5, 771.0 cm–1.
IR (KBr): 3447.8, 3368.3, 3020.7, 2916.1, 1619.0, 1514.0, 1283.1,
818.1, 758.6, 702.8 cm–1.
1H NMR (CDCl3): d = 3.24 (br s, 4 H), 4.00 (br s, 4 H), 6.83–7.49
(m, 19 H).
1H NMR (CDCl3): d = 2.26 (s, 3 H), 2.29 (s, 3 H), 3.71 (br, 2 H),
6.45 (d, J = 8 Hz, 2 H), 6.82 (d, J = 10 Hz, 2 H), 6.89 (s, 4 H), 6.95
(s, 4 H), 7.06 (d, J = 10 Hz, 2 H), 7.11 (m, 3 H).
13C NMR (CDCl3): d = 48.8, 66.9, 114.3, 126.2, 126.3, 127.6,
127.7, 131.4, 131.5, 132.3, 135.1, 139.7, 140.6, 144.1, 144.17,
144.23, 149.4.
13C NMR (CDCl3): d = 21.1, 21.2, 114.4, 126.0, 127.5, 128.2,
128.3, 131.2, 131.3, 131.4, 132.4, 134.5, 135.6, 139.2, 139.9, 141.4,
141.5, 144.5, 144.6.
MS (EI): m/z (%) = 417 (M+, 100), 359 (52), 252 (48).
MS (EI): m/z (%) = 375 (M+, 100), 360 (14), 267 (26), 252 (22), 180
(29).
Anal. Calcd for C30H27NO: C, 86.30; H, 6.52; N, 3.35. Found: C,
86.59; H, 6.76; N, 3.35.
Anal. Calcd for C28H25N: C, 89.56; H, 6.71; N, 3.73. Found: C,
89.77; H, 6.42; N, 3.98.
1-(2-Morpholin-4-ylphenyl)-1,2,2-triphenylethene (5h)
Colorless solid; yield: 61%; mp 173.5–174.7 °C.
1-(4-Fluorophenyl)-1-(2-furyl)-2,2-diphenylethene (5m)
Colorless solid; yield: 70%; mp 147.9–149.1 °C.
IR (KBr): 3074.1, 3029.6, 2851.9, 1597.2, 1490.1, 1448.6, 1112.6,
921.0, 746.1, 736.6, 697.8 cm–1.
IR (KBr): 1597.8, 1505.9, 1490.8, 1442.6, 1213.5, 1157.3, 1020.0,
844.8, 812.0, 766.3, 743.0, 703.3, 595.5 cm–1.
1H NMR (CDCl3): d = 2.58 (br s, 4 H), 3.80 (br s, 4 H), 6.98–7.23
(m, 19 H).
1H NMR (CDCl3): d = 5.71 (d, J = 3.3 Hz, 1 H), 5.84 (d, J = 3.2 Hz,
1 H), 6.27 (dd, J1 = 3.1 Hz, J2 = 1.4 Hz, 1 H), 6.88–7.27 (m, 14 H).
MS (EI): m/z (%) = 417 (M+, 100), 359 (52), 252 (98), 165 (98), 152
(46).
13C NMR (CDCl3): d = 110.9, 112.1, 114.8, 115.0, 126.6, 126.9,
127.6, 127.7, 127.9, 130.1, 131.1, 131.8, 132.8, 132.9, 141.5, 142.0,
142.7, 143.8, 161.3.
Anal. Calcd for C30H27NO: C, 86.30; H, 6.52; N, 3.35. Found: C,
86.01; H, 6.82; N, 3.18.
1-(4-Bromophenyl)-2,2-bis(2-morpholin-4-ylphenyl)-1-phenyl-
ethene (5i)
Yellow solid; yield: 77%; mp 236.1–237.9 °C.
MS (EI): m/z (%) = 340 (M+, 36), 233 (37), 21 (41), 84 (86), 49
(100).
Anal. Calcd for C24H17FO: C, 84.68; H, 5.03. Found: C, 84.41; H,
5.23.
IR (KBr): 3030.0, 2962.1, 2852.7, 1602.8, 1512.0, 1230.4, 1118.5,
923.3, 696.9 cm–1.
1-(4-Morpholin-4-ylphenyl)-2,2-diphenyl-1-(2-thienyl)ethene
(5n)
Yellow solid; yield: 65%; mp 150.5–151.2 °C.
1H NMR (CDCl3): d = 3.23 (m, 8 H), 3.96 (m, 8 H), 6.89 (m, 3 H),
6.91 (m, 3 H), 6.97–7.01 (m, 3 H), 7.12 (m, 5 H), 7.23–7.25 (m, 3
H).
IR (KBr): 2955.8, 2857.0, 2814.0, 1604.9, 1558.4, 1508.3, 1449.7,
1231.3, 1121.1, 929.5, 855.5, 767.6, 700.5 cm–1.
MS (EI): m/z (%) = 580 (M+, 100), 524 (15), 502 (25), 252 (41), 165
(35), 105 (21).
1H NMR (CDCl3): d = 3.15 (t, J = 4.8 Hz, 4 H), 3.86 (t, J = 4.6 Hz,
4 H), 6.61 (s, 1 H), 6.69 (s, 2 H), 6.71 (s, 1 H), 7.06–7.24 (m, 13 H).
Anal. Calcd for C34H33BrN2O2: C, 70.22; H, 4.82; N, 5.72. Found:
C, 69.91; H, 5.81; N, 4.73.
13C NMR (CDCl3): d = 48.8, 66.8, 114.3, 125.9, 126.0, 126.1,
126.8, 127.6, 128.1, 129.4, 130.9, 131.0, 132.2, 133.4, 134.5, 140.2,
143.6, 144.1, 146.9, 149.8.
1-(4-Aminophenyl)-1,2,2-triphenylethene (5j)
Yellow solid; yield: 80%; mp 202.1–203.4 °C.
IR (KBr): 3203.3, 1597.3, 1492.0, 1443.3, 1071.6, 694.4 cm–1.
MS (EI): m/z (%) = 423 (M+, 13), 258 (19), 165 (100), 77 (79).
1H NMR (CDCl3): d = 1.57 (br s, 2 H), 6.69 (m, 2 H), 6.91 (d,
J = 7.8 Hz, 2 H), 7.04 (m, 7 H), 7.16 (m, 8 H).
Anal. Calcd for C28H25NOS: C, 79.40; H, 5.95; N, 3.31. Found: C,
79.48; H, 6.23; N, 3.05;
MS (EI): m/z (%) = 347 (M+, 100), 270 (31), 252 (37), 239 (17), 84
(32).
1-(4-Bromophenyl)-1,2,2-triphenylethene
1-(4-Aminophenyl)-1,2,2-triphenylethene (5j) was diazotized and
brominated according to a published procedure.20 The product was
purified by flash chromatography (petroleum ether). Colorless sol-
id; yield: 76%; mp 160.5–161.5 °C (Lit.17 160–161 °C); analytical
data were in agreement with the structure.
Anal. Calcd for C26H21N: C, 89.88; H, 6.09; N, 4.03. Found: C,
89.84; H, 6.06; N, 4.38.
1-(2-Aminophenyl)-1,2,2-triphenylethene (5k)
Yellow solid; yield: 72%; mp 208.1–209.1 °C.
1-[4-(Chloromethyl)phenyl]-1,2,2-triphenylethene (6)
IR (KBr): 3441.6, 3367.0, 3047.4, 3016.2, 1611.9, 1489.3, 1297.7,
749.7, 699.9 cm–1.
Under an argon atmosphere, ethyl chloroformate (0.74 g, 6.8 mmol)
was added to a soln of 2d (1.5 g, 3.4 mmol) in anhyd MeCN (15
mL). The mixture was refluxed with magnetic stirring for 7 h and
then it was evaporated under vacuum and the residue was taken up
in CH2Cl2 (30 mL). The soln was washed by 2% aq HCl (2 × 20 mL)
and brine (2 × 20 mL) and dried (anhyd Na2SO4). The solvent was
removed to give the crude product. Flash chromatography (petro-
1H NMR (CDCl3): d = 6.58–6.62 (m, 2 H), 6.95 (d, J = 1.5 Hz, 1 H),
6.97 (d, J = 1.5 Hz, 1 H), 7.09–7.11 (m, 12 H), 7.16–7.17 (m, 3 H).
MS (EI): m/z (%) = 347 (M+, 100), 270 (93), 80 (57), 65 (86), 152
(47).
Synthesis 2007, No. 5, 713–718 © Thieme Stuttgart · New York

718
X.-F. Duan et al.
PAPER
(8) (a) Hill, D. H.; Parvez, M. A.; Sen, A. J. Am. Chem. Soc.
1994, 116, 2889. (b) Tezuka, Y.; Hashimoto, A.; Ushizaka,
K.; Imai, K. J. Org. Chem. 1990, 55, 329. (c) Khurana, J.
M.; Maikap, G. C.; Mehta, S. Synthesis 1990, 731.
(9) (a) Suzuki, H.; Tani, H.; Takeuchi, S. Bull. Chem. Soc. Jpn.
1985, 58, 2421. (b) Alper, H.; Ripley, S.; Prince, T. L. J.
Org. Chem. 1983, 48, 250.
leum ether) gave the pure product as a colorless solid; yield: 87%;
mp 178.6–179.2 °C.
IR (KBr): 3024.9, 2925.2, 1607.9, 1513.4, 1235.5, 1010.4, 699.6
cm–1.
1H NMR(CDCl3): d = 4.53 (s, 2 H), 7.05–7.17 (m, 19 H).
13C NMR (CDCl3): d = 46.1, 126.5, 126.6, 127.6, 127.7, 127.8,
127.9, 128.1, 128.5, 128.7, 128.9, 129.3, 131.3, 131.6, 135.4, 140.3,
141.5, 143.5, 143.6, 143.9.
(10) (a) Plater, M. J.; Jackson, T. Tetrahedron 2003, 59, 4673.
(b) Fürstner, A.; Hupperts, A. J. Am. Chem. Soc. 1995, 117,
4468.
MS (EI): m/z (%) = 380 (M+, 100), 345 (71), 252 (42), 167 (43), 84
(72), 49 (74).
(11) (a) Zhou, C. X.; Larock, R. C. Org. Lett. 2005, 7, 259.
(b) Zhou, C. X.; Larock, R. C. J. Org. Chem. 2005, 70,
3765. (c) Obora, Y.; Moriya, H.; Tokunaga, M.; Tsuji, Y.
Chem. Commun. 2003, 2820. (d) Rathore, R.; Deselnicu, M.
I.; Burns, C. L. J. Am. Chem. Soc. 2002, 124, 14832.
(12) For reviews on the McMurry reaction, see: (a)Ephritikhine,
M. Chem. Commun. 1998, 2549. (b) Fürstner, A.;
Bogdanovic, B. Angew. Chem., Int. Ed. Engl. 1996, 35,
2442; Angew. Chem., 1996, 108, 2582. (c) McMurry, J. E.
Chem. Rev. 1989, 89, 1513. (d) Lenoir, D. Synthesis 1989,
883.
Anal. Calcd for C27H21Cl: C, 85.14; H, 5.56. Found: C, 84.83; H,
5.42.
Acknowledgment
We gratefully acknowledged the National Nature Science Founda-
tion of China (20672014) and the generous support from Beijing
Synth. Sky Chem. Tech. Ltd.
(13) McMurry, J. E.; Krepski, L. R. J. Org. Chem. 1976, 41,
3929.
References
(14) Cross McMurry reactions have been used as the key step in
the synthesis of the antitumor agent tamoxifen and its
analogues and the antihistamine drug loratadine. For
references on the synthesis of tamoxifen and its analogues
via the cross McMurry reaction, see: (a) Castedo, L.; Saa, J.
M.; Suau, R.; Tojo, G. Tetrahedron Lett. 1983, 24, 5419.
(b) Gauthier, S.; Mailhot, J.; Labrie, F. J. Org. Chem. 1996,
61, 3890. (c) Detsi, A.; Koufaki, M.; Calogeropoulou, T.
J. Org. Chem. 2002, 67, 4608. (d) Yu, D. D.; Forman, B. M.
J. Org. Chem. 2003, 68, 9489. (e) Uddin, J.; Rao, P. N. P.;
Knaus, E. E. Synlett 2004, 513. (f) Pigeon, P.; Top, S.;
Vessiéres, A.; Huché, M.; Hillard, E. A.; Salomon, E.;
Jaouen, G. J. Med. Chem. 2005, 48, 2814. For loratadine,
see the patents: (g) Alberto, S.; Pelayo, C.; Gloria, R.;
Bosch Onrubia, J.; Carmen, M. US 6084100, 2000; Chem.
Abstr., 2000, 133, 73940f. (h) Jackson, W. P. WO 9838166,
1998; Chem. Abstr., 1998, 129, 230642.
(1) (a) Rathore, R.; Lindeman, S. V.; Kumar, A. S.; Kochi, J. K.
J. Am. Chem. Soc. 1998, 120, 6931. (b) Barbosa, F.; Peron,
V.; Gescheidt, G.; Fürstner, A. J. Org. Chem. 1998, 63,
8806. (c) Zijlstra, R. W. J.; Duijnen, P. Th.; Feringa, B. L.;
Steffen, T.; Duppen, K.; Wiersma, D. A. J. Phys. Chem. A
1997, 101, 9828. (d) Ma, J.; Dutt, G. B.; Waldeck, D. H.; Zi,
M. B. J. Am. Chem. Soc. 1994, 116, 10619. (e) Sun, Y.-P.;
Bunker, C. E. J. Am. Chem. Soc. 1994, 116, 2430.
(2) (a) Bosch, E.; Kochi, J. K. J. Am. Chem. Soc. 1996, 118,
1319. (b) Schultz, D. A.; Fox, M. A. J. Org. Chem. 1990, 55,
1047. (c) Leigh, W. J.; Arnold, D. R. Can. J. Chem. 1981,
59, 3061. (d) Garst, J. F.; Zablotny, E. R.; Cole, R. S. J. Am.
Chem. Soc. 1964, 86, 2257.
(3) Schultz, A.; Diele, S.; Laschat, S.; Nimtz, M. Adv. Funct.
Mater. 2001, 11, 441.
(4) (a) Ito, A.; Nakano, Y.; Kato, T.; Tanaka, K. Chem.
Commun. 2005, 403. (b) Mori, T.; Inoue, Y. J. Phys. Chem.
A 2005, 109, 2728.
(15) Gauthier, S.; Mailhot, J.; Labrie, F. J. Org. Chem. 1996, 61,
3890.
(5) (a) Fujita, M.; Qi, G.; Verkerk, U. H.; Dzwiniel, T. L.;
McDonald, R.; Stryker, J. M. Org. Lett. 2004, 6, 2653.
(b) Verkerk, U.; Fujita, M.; Dzwiniel, T. L.; McDonald, R.;
Stryker, J. M. J. Am. Chem. Soc. 2002, 124, 9988.
(6) Koichi, T.; Daisuke, F.; Thomas, O.; Hermann, I.; Fumio, T.
Chem. Commun. 2000, 413.
(7) (a) Monguchi, K.; Itoh, T.; Hirai, K.; Tomioka, H. J. Am.
Chem. Soc. 2004, 126, 11900. (b) Okuma, K.; Kojima, K.;
Oyama, K.; Kubo, K.; Shioji, K. Eur. J. Org. Chem. 2004,
820.
(16) Rele, S.; Chattopadhyay, S.; Nayak, S. K. Tetrahedron Lett.
2001, 42, 9093.
(17) Murray, R. W.; Trozzolo, A. M. J. Org. Chem. 1962, 27,
3341.
(18) Zhou, C. X.; Larock, R. C. J. Org. Chem. 2005, 70, 3765.
(19) Itami, K.; Mineno, M.; Muraoka, N.; Yoshida, J. J. Am.
Chem. Soc. 2004, 126, 11778.
(20) Hartwell, J. L. Org. Synth. Coll. Vol. III; John Wiley & Sons:
London, 1955, 185.
Synthesis 2007, No. 5, 713–718 © Thieme Stuttgart · New York