Divergent synthesis of benzene derivatives: Bronsted acid catalyzed and iodine-promoted tandem cyclization of 5,2-enyn-1-ones

Article abstract of DOI:10.1021/jo301567p

Highly substituted benzene derivatives, including alkoxy-, iodoalkoxy-, and diiodo-substituted benzenes, can be selectively synthesized via Bronsted acid catalyzed and iodine-promoted tandem carbocyclization respectively. This reaction involved a direct p

Full text of DOI:10.1021/jo301567p

Article
pubs.acs.org/joc
Divergent Synthesis of Benzene Derivatives: Brønsted Acid Catalyzed
and Iodine-Promoted Tandem Cyclization of 5,2-Enyn-1-ones
Fang Yang, Yi-Feng Qiu, Ke-Gong Ji, Yan-Ning Niu, Shaukat Ali, and Yong-Min Liang*
State Key Laboratory of Applied Organic Chemistry, Lanzhou University, and State Key Laboratory of Solid Lubrication, Lanzhou
Institute of Chemical Physics, Chinese Academy of Science, Lanzhou 730000, People's Republic of China
S
* Supporting Information
ABSTRACT: Highly substituted benzene derivatives, includ-
ing alkoxy-, iodoalkoxy-, and diiodo-substituted benzenes, can
be selectively synthesized via Brønsted acid catalyzed and
iodine-promoted tandem carbocyclization respectively. This
reaction involved a direct process for C−C bond formation
from 5,2-enyn-1-ones, and different reaction systems
(Brønsted acids/electrophiles with solvents) afforded different
substituted benzenes. Furthermore, the halogenated moiety
and alkoxy group can be readily introduced into the benzene in
a position which has not been easily obtained previously.
Scheme 1. Design of Proposed Cyclization for the Synthesis
of Benzene Derivatives
INTRODUCTION
■
The development of novel methods for the annulation of highly
substituted benzene derivatives is very important in organic
chemistry, because such substituted aromatic compounds are
essential intermediates/substrates for organic synthesis.1 They
are also important structural units found in organic materials,
such as optical and conductive materials. Traditionally,
substituted benzenes are synthesized from benzene directly
through various functionalization reactions.2 However, the
activation or deactivation of the benzene ring in the functional
substitution may be correlated with the electron-donating or
electron-withdrawing influence of the substituents, during
which the selectivity is a problem, especially in introducing
one group into the benzene in a special position. Moreover,
benzene derivatives have also been synthesized by cyclo-
trimerization of alkynes with transition-metal catalysts, but one
of the major problems with these reaction systems is the
difficulty of regioselective intermolecular cyclotrimerization
with unsymmetrical alkynes, which generally give a mixture of
the multisubstituted benzene derivatives.3 Thus, an ideal
solution to construct benzenes directly from a suitably designed
nonaromatic system is still of current demand. Previously, we
have shown that an iodine-promoted carbocyclization of
hydroxylated enynes can serve this purpose (Scheme 1a).4a
However, this reaction was completed in two steps and
involved the use of an oxidant. In order to remove these
shortcomings and have a more efficient benzene-forming
reaction, we designed 5,2-enyn-1-ones as precursors for
cyclization.
need to be examined. We were convinced that Brønsted acids
would activate the carbonyl group of 5,2-enyn-1-ones 1, which
favors Michael addition.4b,5 Moreover, iodine could also induce
electrophilic carbocyclization6 of 5,2-enyn-1-ones 1, in which
the key step might be the attack of unactivated olefins on
allenes promoted by the iodonium ion.4a Herein, we report a
successful realization of Brønsted acid catalyzed and iodine-
Recently, our group has reported Brønsted acid catalyzed
cycloisomerizations of 5,2-enyn-1-ones I with R2 (Me, H,
CH2Cl, CH2OAc) for the regioselective synthesis of a new type
of dihydropyranones II (Scheme 1b).4b To further develop this
type of strategy, other structural differences of the substrate
Received: July 24, 2012
Published: September 19, 2012
© 2012 American Chemical Society
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induced selective synthesis of highly substituted benzene
derivatives from the 5,2-enyn-1-ones 1 (Scheme 1c). This
chemistry offers a good method for the synthesis of a broad
range of alkoxy-, iodoalkoxy-, and diiodo-substituted benzenes,
which are of synthetic importance in both academia and
industry.
Table 2. Optimization of Electrophilic Carbocyclization for
the Synthesis of 4a and 5a
a
RESULTS AND DISCUSSION
yield (%)
■
Initially, we attempted to extend the scope of our previously
reported reaction of synthesizing dihydropyranone II4b by
employing 1,5-diphenylhex-5-en-2-yn-1-one (1a) and p-TsOH
(10 mol %) in methanol (Scheme 1b). Unexpectedly, the
dihydropyranone product was not detected, but the benzene
derivative 5′-methoxy-1,1′:3′,1″-terphenyl (2a; 60%) was
obtained along with 30% of 3,3-dimethoxy-1-phenylpropan-1-
one (3a),7 which indicated that the cyclization process
employed simple olefins as internal carbon nucleophiles to
form the C−C bond (Table 1, entry 1). Then, the optimization
amt of I2
(equiv)
temp
time
(h)
entry
solvent
(°C)
4a
5a
6a
b
1
CH2Cl2
DCE
2
2
rt
10
10
7
12
10
50
48
65
20
c
2
rt
3
CH3NO2
MeOH
MeOH
MeOH
MeOH
MeOH
MeOH
MeOH
CH3NO2
CH3NO2
CH3NO2
2
rt
25
d
4
2
rt
10
2
45
62
56
70
54
55
63
trace
trace
trace
5
2
65
65
65
65
75
55
65
65
65
6
3
1.5
2
7
1.5
1.2
1.5
1.5
1.5
1.1
1.0
8
2
9
1.5
3
10
11
12
13
Table 1. Optimization of Cascade Cyclization for the
a
10
10
10
66
70
67
trace
trace
trace
Synthesis of 2a
a
Reaction conditions: 1a (0.2 mmol) and solvent (3.0 mL) in the
b
c
presence of I2. 30% of 1a was recovered. 39% of 1a was recovered.
d
25% of 1a was recovered.
yield (%)
Changing the solvent from CH2Cl2 to DCE or CH3NO2
slightly influenced this transformation (Table 2, entries 2 and
3). Delightfully, using methanol as a solvent gave 45% of 4′-
iodo-5′-methoxy-1,1′:3′,1″-terphenyl (4a) and a trace amount
of 5a (Table 2, entry 4). Increasing the temperature to 65 °C
and decreasing the amount of I2 to 1.5 equiv improved the yield
of 4a to 70% (Table 2, entries 5−10). The conditions for
selective synthesis of 5a were also extensively screened (Table
2, entries 11−13). Finally, we found that the optimized reaction
conditions for 4a were 1.5 equiv of I2 in methanol at 65 °C
(Table 2, entry 7), whereas the standard conditions for 5a were
selected as I2 (1.1 equiv) in CH3NO2 at 65 °C (Table 2, entry
12).
Under the optimized conditions, various representative 5,2-
enyn-1-ones 1a−q were then subjected to the optimized
conditions for the synthesis of methoxybenzene derivatives 2,
as depicted in Table 3. The reaction works well with aromatic
R1 and R2 groups. Electron-rich aryl groups showed better
results than those with an electron-withdrawing group in this
carbocyclization (2b−d vs 2f,g, 2m vs 2n, and 2o vs 2p).
Actually, R2 with an electron-donating group would influence
the stability of the intermediate M, as delineated in Scheme 5.
The steric effect was also investigated in this reaction:
substrates such as 1e,j,q with a more hindered group gave
the corresponding products in lower yields, indicating that the
steric effect plays a major role in this transformation. Substrates
with a heteroaromatic moiety or an aliphatic group afforded the
desired products 2h,i,l in yields of 49%, 41%, and 39%,
respectively. When a substrate with styrene R1 group and two
olefin groups was subjected to the optimal reaction conditions,
it was found that the corresponding 2k was not generated. This
might be due to the fact that the styrene nucleus is not stable in
this reaction system.
entry
cat. (amt (mol %))
temp (°C)
time (h)
2a
3a
1
p-TsOH (10)
TfOH (10)
TFA (10)
75
75
75
75
75
75
75
75
85
65
55
12
12
12
2
60
55
34
38
15
41
36
39
2
b
3
28
51
50
47
74
70
63
78
72
4
HAuCl4·4H2O
Sc(OTf)3
5
6
6
Bi(OTf)3
6
7
p-TsOH (5)
p-TsOH (2)
p-TsOH (5)
p-TsOH (5)
p-TsOH (5)
12
12
7
8
9
10
11
12
12
a
Reaction conditions: 1a (0.2 mmol) and MeOH (3.0 mL) in the
presence of Brønsted or Lewis acids. 50% of 1a was recovered.
b
studies of this novel cascade reaction were performed by using
1a with different Brønsted acids, as shown in Table 1. Of these,
p-TsOH proved to be the most efficient catalyst. A variety of
Lewis acids such as HAuCl4·4H2O, Sc(OTf)3, and Bi(OTf)3
were also screened; however, no superior yield of 2a was
obtained (Table 1, entries 4−6). When the p-TsOH loading
was decreased to 5 mol %, the yield of 2a was increased to 74%
and 3a was also not generated (Table 1, entries 7 and 8). When
we decreased the temperature to 65 °C, 2a was isolated in 78%
yield after 12 h (Table 1, entry 10). Thus, the use of p-TsOH
(5 mol %) in methanol at 65 °C was considered to be optimal
reaction conditions to form 2a.
In the context of our ongoing efforts to construct C−X (X =
C, N, O) bonds by electrophilic cyclization of alkynes with
nucleophiles,8 we envisioned that this type of 5,2-enyn-1-ones 1
could realize this purpose for the construction of halogenated
benzene derivatives. When we treated 1a with molecular iodine
(2.0 equiv) in CH2Cl2 at room temperature, to our delight, 10%
of 4′,5′-diiodo-1,1′:3′,1″-terphenyl (5a) was obtained along
with 50% of the addition product 6a (Table 2, entry 1).
Next, to examine the scope of the electrophilic carbocycliza-
tion, we also investigated a wide range of 5,2-enyn-1-ones 1a−q
with different aromatic R1 and R2 groups in the presence of I2
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a
Table 3. Synthesis of Methoxy- and Iodomethoxy-Substituted Benzenes 2 and 4 from 5,2-Enyn-1-ones 1
yield (%)
entry
substrate (R1, R2)
Ph, Ph
2
4
1
78 (2a)
70 (2b)
86 (2c)
60 (2d)
20 (2e)
66 (2f)
60 (2g)
49 (2h)
41 (2i)
70 (4a)
63 (4b)
72 (4c)
55 (4d)
2
p-MeC6H4, Ph
p-OMeC6H4, Ph
m-OMeC6H4, Ph
2,5-dimethoxy, Ph
p-ClC6H4, Ph
3
4
b
5
trace (4e)
6
70 (4f)
65 (4g)
7
m-ClC6H4, Ph
2-thienyl, Ph
c
8
35 (4h)
9
2-furyl, Ph
45 (4i)
58 (4j)
62 (4k)
51 (4l)
10
11
12
13
14
15
16
17
piperonyl, Ph
40 (2j)
d
styryl, Ph
−
(2k)
n-propyl, Ph
39 (2l)
e
Ph, p-MeC6H4
Ph, p-ClC6H4
78 (2m)
76 (2n)
81 (2o)
62 (2p)
trace (2q)
47 (4m)
f
35 (4n)
g
p-OMeC6H4, p-MeC6H4
p-OMeC6H4, p-ClC6H4
1-naphthyl, Ph
45 (4o)
57 (4p)
trace (4q)
a
Conditions for 2: the reaction was carried out by using 1 (0.2 mmol) and 5 mol % of p-TsOH in methanol (3 mL) at 65 °C. Conditions for 4: the
b
c
reaction was carried out by using 1 (0.2 mmol) and 1.5 equiv of I2 in methanol (3 mL) at 65 °C. 20% of 5e was isolated. 20% of 5h was isolated.
d
e
f
g
Decomposed. 12% of 5h was isolated. A trace amount of 5n was observed. 20% of 5o was isolated.
a
in methanol. It was found that these substrates (except 1e,q)
were effectively converted into the corresponding iodomethox-
ybenzene derivatives 4a−p in moderate to good yield, as
depicted in Table 3. The reaction tolerates the presence of
different electron-rich and electron-withdrawing aryl groups.
The steric effect was also tolerated in this reaction.
Unfortunately, with a substrate such as 1e with a 2,5-dimethoxy
aryl group, just a trace amount of the desired product 4e was
observed, while the diiodo-substituted benzene 5e was obtained
in 20% yield. This might be due to the fact that the
intermediate cation D was more easily captured by iodide
anion than methanol in this case (Scheme 5). Other substrates
such as 1h,m−o, in addition to the desired iodomethoxy-
substituted benzenes 4h,m−o were obtained in moderate yield;
diiodo-substituted benzenes 5h,m−o were also observed.
Interestingly, in comparison with p-TsOH-catalyzed cyclization
for the synthesis of 2k, substrate 1k with a styrene R1 group has
little effect on this carbocyclization and 4k was isolated in 62%
yield.
Table 4. Selective Synthesis of Diiodobenzene Derivatives 5
entry
substrate (R1, R2)
Ph, Ph
time (h)
yield (%)
1
2
3
4
5
6
7
8
10
12
12
10
7
70 (5a)
52 (5b)
63 (5f)
55 (5j)
74 (5k)
46 (5m)
44 (5o)
43 (5q)
p-MeC6H4, Ph
p-ClC6H4, Ph
piperonyl, Ph
styryl, Ph
Ph, p-MeC6H4
p-OMeC6H4, p-MeC6H4
1-naphthyl, Ph
10
10
12
a
The reaction was carried out by using 1 (0.2 mmol) and 1.1 equiv of
I2 in CH3NO2 (3 mL) at 65 °C.
Furthermore, we also investigated the selective synthesis of
diiodobenzene derivatives 5 via iodine-promoted electrophilic
carbocyclization, as depicted in Table 4. Thus, a tandem
carbon−carbon bond formation of 5,2-enyn-1-one derivatives
proceeded smoothly to afford the corresponding products in
moderate yields. The reaction works well with aromatic R
groups. Fortunately, when 5,2-enyn-1-one 1k with two olefin
groups was subjected to the above conditions, it was found that
the styrene group was selectively retained in this reaction and a
good yield of the corresponding 5k was obtained. Interestingly,
it was found that for substrate 1q, just trace amounts of 2q and
4q can be observed, while 5q can be isolated in a yield of 43%.
Knowing the importance of polycyclic derivatives in organic
materials,9 which are used for the preparation of many optical
and conductive materials, we also prepared the symmetrical 5,2-
enyn-1-one substrate 1r, and it was found that by increasing the
amount of corresponding catalyst loading, the expected
products 2r and 4r were obtained in yields of 30% and 27%,
respectively (Scheme 2).
Furthermore, to exploit the synthetic utility of this reaction,
we also investigated the influence of different alcohols (Scheme
3). It was found that 1a in the presence of 5 mol % p-TsOH
with ethanol as solvent gave the corresponding 2aa in low yield
(20%), whereas phenol failed to give the product, which might
be due to the more hindered nature of the nucleophile in the
nucleophilic attack step. The role of the alcohol in electrophilic
carbocyclization was also investigated. When the reaction was
performed in ethanol, 4aa was obtained in a yield of 57%. Not
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Scheme 2. Synthesis of Polycyclic Derivatives 2r and 4r
bond to form B (or F and J).12 Attack of the electrophile
(iodine cation) onto the allene B (or F) affords C (or G). The
activation of the carbonyl precedes the intramolecular
nucleophlic attack by the alkene moiety, thereby generating a
newly formed carbon−carbon bond (D or H),13 which
undergoes deprotonation and dehydration to give product 4
(or 5). The mechanism for 2 was also proposed. J releases a
proton; a subsequent keto−enol tautomerization would lead to
the formation of intermediate K and regenerate the acid
catalyst. Owing to the steric hindrance, K on heating undergoes
subsequent convertion to L (allylic substrates with methyl as
the R2 group afforded a significant amount of lactone derivative,
presumably through the competitive intramolecular nucleo-
philic addition of the oxygen of the carbonyl group to the
alkene group position).4b Attack of the terminal olefin at the
carbonyl carbon of L affords M, which undergoes deprotona-
tion and dehydration to give product 2.
Scheme 3. Influence of Different Alcohols on the Outcome
of Reaction
surprisingly, using phenol as solvent, the 1-iodo-2-oxybenzene
derivative was not afforded but 5a was generated in 62% yield.
A standard feature of this process is the fact that the iodo-
substituted benzenes produced by carbocyclization can be
further elaborated by using various palladium-catalyzed
processes. For example, the Sonagashira coupling10 of 4a and
5a afforded the corresponding products 4ab and 5ab in
excellent yields (Scheme 4).
On the basis of the above observations and the isolation of
intermediate,11 a possible reaction mechanism is proposed as
shown in Scheme 5. Initial interaction of the proton generated
from iodine and protic solvents (or from the Brønsted acid)
with the carbonyl oxygen atom of 1 gives complex A. Alcohol
(or iodide) as nucleophiles attacks the carbon−carbon triple
CONCLUSION
■
In summary, we have reported a direct and highly selective
protocol for preparing different alkoxy-, iodoalkoxy-, and
diiodobenzene derivatives from 5,2-enyn-1-ones in the presence
of Brønsted acid or molecular iodine. The reaction involves an
efficient process for C−C bond formation, and the product
nature is tunable by the steric hindrance of the nucleophile and
the substituted groups of the starting materials. The resulting
iodobenzene derivatives can be further functionalized by using
known organopalladium chemistry.
EXPERIMENTAL SECTION
■
General Procedure A: Synthesis of 5,2-Enyn-1-ones 1.4 For
the synthesis of 1a: to a stirred solution of 1-phenyl-2-propyn-1-ol (A;
Scheme 4. Palladium-Catalyzed Sonogashira Coupling
Reaction
10 mmol) in dry DMF (10 mL) under argon were sequentially added
K2CO3 (1.93 g, 14 mmol), tetrabutylammonium bromide (483 mg, 1.5
mmol), and copper(I) iodide (96 mg, 0.5 mmol) at room temperature.
After 15 min, (3-bromoprop-1-en-2-yl)benzene (15 mmol) was added.
The reaction mixture was stirred for 24 h. Then it was poured into
water and extracted with ether. The combined organic layers were
washed with a saturated aqueous sodium chloride solution, dried over
Na2SO4, and filtered, and the solvents were removed under reduced
pressure. The residue was purified by flash column chromatography
(silica gel, petroleum ether/ethyl acetate 10/1) to give the
corresponding propargylic alcohol (80%).
MnO2 (75 mmol, 15 equiv) was added to a solution of 1,5-
diphenylhex-5-en-2-yn-1-ol (5 mmol) in CH2Cl2 (10 mL) at room
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Scheme 5. Proposed Mechanisms
temperature. The resulting mixture was stirred overnight. Then the
solid was filtered and the solvents were removed under reduced
pressure. The residue was purified by flash column chromatography
(silica gel, petroleum ether/ethyl acetate 20/1) to give 5,2-enyn-1-one
1a (75%).
142.7, 141.2, 133.6, 128.7, 128.3, 127.5, 127.3, 118.5, 114.2, 111.4,
111.1, 55.4, 55.3; IR (neat, cm−1): 2924, 2853, 1594, 1576, 1514, 1460,
1423, 1382, 1252, 1206, 1176, 1027, 887.6, 828.6, 762, 700, 642;
HRMS (ESI) calcd for C20H18O2 ([M + H]+) 291.1380, found
291.1393.
General Procedure B: Synthesis of Methoxy-Substituted
Benzenes 2. To a solution of 5,2-enyn-1-one 1 (0.20 mmol) in
MeOH (3.0 mL) was added 5 mol % of p-TsOH. The resulting
mixture was stirred at 65 °C. When the reaction was considered
complete as determined by TLC analysis, the reaction mixture was
diluted with ethyl ether (40 mL), washed with water and saturated
brine, dried over Na2SO4, and evaporated under reduced pressure. The
residue was purified by chromatography on silica gel to afford the
corresponding products 2.
General Procedure C: Synthesis of Iodomethoxy and
Diiodobenzene Derivatives 4 and 5. To a solution of 5,2-enyn-
1-one 1 (0.20 mmol) in MeOH (3.0 mL) was added 1.5 equiv of I2.
The resulting mixture was stirred at 65 °C. When the reaction was
considered complete as determined by TLC analysis, the reaction
mixture was quenched with a saturated aqueous solution of Na2S2O3,
diluted with ethyl ether (40 mL), washed with water and saturated
brine, dried over Na2SO4, and evaporated under reduced pressure. The
residue was purified by chromatography on silica gel to afford products
4 and 5.
3,5′-Dimethoxy-1,1′:3′,1″-terphenyl (2d): yield 60%; light yellow
oil; 1H NMR (400 MHz, CDCl3) δ 7.56−7.54 (m, 2H), 7.36 (t, J = 7.6
Hz, 2H), 7.31−7.28 (m, 3H), 7.15−7.13 (m, 1H), 7.08 (t, J = 2.0 Hz,
1H), 7.03 (s, 2H), 6.83 (dd, J = 8.4 Hz, 2.4 Hz, 1H), 3.82 (s, 3H),
3.78(s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 160.24, 159.9,
143.1, 143.0, 142.6, 141.1, 129.8, 128.8, 127.5, 127.3, 119.8, 118.9,
113.0, 112.9, 111.9, 111.8, 55,4, 55.4, 55.3, 55.3; IR (neat, cm−1):
2920, 2851, 1580, 1542, 1494, 1462, 1403, 1384, 1212, 1171, 1071,
1042, 853, 762, 698; HRMS (ESI) calcd for C20H18O2 ([M + H]+)
291.1380, found 291.1390.
2,5,5′-Trimethoxy-1,1′:3′,1″-terphenyl (2e): yield 20%; light yellow
oil; 1H NMR (400 MHz, CDCl3) δ 7.63−7.61 (m, 2H), 7.44 (t, J = 7.6
Hz, 2H), 7.37−7.33 (m, 2H), 7.11−7.09 (m, 2H), 6.97−6.92 (m, 2H),
6.87 (dd, J = 9.2 Hz, 3.2 Hz, 1H), 3.89 (s, 3H), 3.81 (s, 3H), 3.78 (s,
3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 159.6, 153.7, 150.8,
142.4, 141.2, 140.1, 131.5, 128.7, 127.4, 127.3, 121.1, 116.7, 114.1,
113.4, 112.7, 111.8, 56.4, 55.8, 55.4; IR (neat, cm−1): 2922, 2852,
1591, 1541, 1499, 1461, 1384, 1219, 1045, 1028, 859, 803, 763, 730,
699; HRMS (ESI) calcd for C21H20O3 ([M + H]+) 321.1485, found
321.1485.
General Procedure D: Synthesis of Diiodo-Substituted
Benzenes 5. To a mixture of 5,2-enyn-1-one 1 in CH3NO2 (3.0
mL) was added 1.1 equiv of I2. The resulting mixture was then stirred
at 65 °C. When the reaction was considered complete as determined
by TLC, the reaction mixture was quenched with a saturated aqueous
solution of Na2S2O3 and extracted with ethyl acetate. The combined
organic extracts were washed with water and saturated brine, dried
over Na2SO4, and evaporated under reduced pressure. The residue was
purified by chromatography on silica gel to afford products 5.
Characterization Data of 2a−r. 5′-Methoxy-1,1′:3′,1″-terphenyl
4-Chloro-5′-methoxy-1,1′:3′,1″-terphenyl (2f): yield 66%; orange
1
oil; H NMR (400 MHz, CDCl3) δ 7.64−7.61 (m, 2H), 7.56 (d, 8.8
Hz, 2H), 7.47−7.35 (m, 6H), 7.12 (t, J = 1.6 Hz, 1H), 7.60 (t, J = 2.0
Hz, 1H), 3.91 (s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 160.4,
143.4, 141.9, 141.0 139.5, 133.6, 128.9, 128.8, 128.5, 127.7, 127.3,
118.7, 112.0, 111.6, 55.5; IR (neat, cm−1): 2923, 2852, 1594, 1496,
1461, 1421, 1388, 1207, 1175, 1091, 1073, 1017, 824, 762, 699;
HRMS (ESI) calcd for C19H15ClO ([M + H]+) 295.0884, found
295.0887.
1
(2a): yield 78%; light yellow solid; mp 92−94 °C; H NMR (400
3-Chloro-5′-methoxy-1,1′:3′,1″-terphenyl (2g): yield 60%; color-
MHz, CDCl3) δ 7.63 (d, J = 7.2 Hz, 4H), 7.46 (t, J = 8.0 Hz, 4H),
7.40−7.35 (m, 3H), 7.14 (d, J = 1.2 Hz, 2H), 3.92 (s, 3H); 13C NMR
(100 MHz, CDCl3) δ (ppm) 160.3, 143.2, 141.1, 128.8, 127.5, 127.3,
118.9, 111.8, 55.5; IR (neat, cm−1): 2923, 1594, 1495, 1458, 1409,
1382, 1205, 1071, 1023, 859, 759, 696; HRMS (ESI) calcd for
C19H16O ([M + H]+) 261.1274, found 261.1274.
1
less oil; H NMR (400 MHz, CDCl3) δ 7.62 (d, J = 7.6 Hz, 3H),
7.51−7.44 (m, 3H), 7.39−7.32 (m, 4H), 7.13 (t, J = 1.6 Hz, 1H), 7.06
(t, J = 2.0 Hz, 1H) 3.91 (s, 3H); 13C NMR (100 MHz, CDCl3) δ
(ppm) 160.4, 143.4, 142.9, 141.7, 140.9, 134.6, 130.0, 128.8, 127.7,
127.5, 127.4, 127.3, 125.4, 118.8, 112.3, 111.6, 55.5; IR (neat, cm−1):
2922, 2851, 1593, 1570, 1497, 1460, 1422, 1393, 1207, 1175, 1074,
1040, 848, 784, 762, 719, 696; HRMS (ESI) calcd for C19H15ClO ([M
+ H]+) 295.0884, found 295.0885.
2-(5-Methoxy-[1,1′-biphenyl]-3-yl)thiophene (2h): yield 50%;
yellow oil; 1H NMR (400 MHz, CDCl3) δ 7.63 (d, J = 1.2 Hz,
2H), 7.61−7.35 (m, 5H), 7.29 (dd, J = 5.2 Hz, 0.8 Hz, 1H), 7.13 (t, J =
2.0 Hz, 1H), 7.09 (dd, J = 4.8 Hz, 3.6 Hz, 1H), 7.05 (t, J = 2.0 Hz, 1H)
3.91 (s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 160.3, 144.2,
143.4, 140.9, 136.0, 128.8, 128.8, 128.0, 127.7, 127.2, 127.2, 125.0,
123.5, 117.8, 112.1, 110.5, 55.5; IR (neat, cm−1): 2922, 2854, 1563,
1455, 1262, 1095, 1024, 873, 806, 760, 698; HRMS (ESI) calcd for
C17H14OS ([M + H]+) 267.0838, found 267.0841.
5′-Methoxy-4-methyl-1,1′:3′,1″-terphenyl (2b): yield 70%; white
oil; 1H NMR (400 MHz, CDCl3) δ 7.63 (d, J = 8.0 Hz, 2H), 7.54 (d, J
= 7.6 Hz, 2H), 7.45 (t, J = 7.6 Hz, 2H), 7.39−7.34 (m, 2H), 7.25(d, J
= 4.0 Hz, 2H), 7.09 (s, 2H), 3.91 (s, 3H), 2.40 (s, 3H); 13C NMR
(100 MHz, CDCl3) δ (ppm) 160.3 143.1, 143.1, 141.2, 138.2, 137.4,
129.5, 128.7, 127.5, 127.3, 127.1, 118.7, 111.6, 111.5, 55.4, 21.1; IR
(neat, cm−1): 2922, 2852, 1594, 1574, 1515, 1460, 1420, 1382, 1205,
1071, 1023, 815, 761, 698; HRMS (ESI) calcd for C20H18O ([M +
H]+) 275.1430, found 275.1433.
4,5′-Dimethoxy-1,1′:3′,1″-terphenyl (2c): yield 86%; yellow solid;
1
mp 62−64 °C; H NMR (400 MHz, CDCl3) δ 7.63 (d, J = 7.6 Hz,
2H) 7.59−7.55 (m, 2H), 7.45 (t, 8.0 Hz, 2H), 7.38−7.34 (m, 2H),
7.07 (d, J = 1.2 Hz, 2H), 6.98 (d, J = 8.8 Hz, 2H), 3.90 (s, 3H), 3.85
(s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 160.3, 159.3, 143.1,
2-(5-Methoxy-[1,1′-biphenyl]-3-yl)furan (2i): yield 40%; colorless
oil; 1H NMR (400 MHz, CDCl3) δ 7.62 (d, J = 5.2 Hz, 2H), 7.5−7.43
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(m, 4H), 7.39−7.35 (m, 1H), 7.21−7.20 (m, 1H), 7.03 (dd, J = 2.4
Hz, 1.6 Hz, 1H), 6.70−6.70 (m, 1H), 6.49 (q, J = 1.6 Hz, 1H), 3.91 (s,
3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 160.3, 153.8, 143.2,
142.2, 140.9, 132.5, 128.7, 127.6, 127.2, 115.5, 112.2, 111.7, 108.0,
105.5, 55.5; IR (neat, cm−1): 2923, 2853, 1597, 1573, 1496, 1460,
1381, 1208, 1155, 1069, 1022, 869, 802, 761, 697; HRMS (ESI) calcd
for C17H14O2 ([M + H]+) 251.1067, found 251.1066.
Characterization Data of 4a−r. 4′-Iodo-5′-methoxy-1,1′:3′,1″-
terphenyl (4a): yield 70%; yellow oil; 1H NMR (400 MHz, CDCl3) δ
7.62−7.60 (m, 2H), 7.46−7.35 (m, 8H), 7.17 (d, J = 2.0 Hz, 1H), 7.01
(d, J = 2.0 Hz, 1H), 4.00 (s, 3H); 13C NMR (100 MHz, CDCl3) δ
(ppm) 158.6, 148.9, 144.5, 142.3, 140.2, 129.3, 128.9, 127.9, 127.8,
127.6, 127.1, 121.6, 108.3, 90.0, 56.7; IR (neat, cm−1): 2924, 1579,
1561, 1492, 1455, 1389, 1065, 1022, 849, 762, 699, 566; HRMS (ESI)
calcd for C19H15IO ([M + H]+) 387.0240, found 387.0243.
5-(5Methoxy-[1,1′-biphenyl]-3-yl)benzo[d][1,3]dioxole (2j): yield
1
6′-Iodo-5′-methoxy-4-methyl-1,1′:3′,1″-terphenyl (4b): yield
40%; white oil; H NMR (400 MHz, CDCl3) δ 7.62 (d, J = 7.2 Hz,
1
63%; light yellow oil; H NMR (400 MHz, CDCl3) δ 7.60−7.58(m,
2H), 7.44 (t, J = 7.6 Hz, 2H), 7.36 (t, J = 7.2 Hz, 1H), 7.32 (s, 1H),
7.11−7.07 (m, 3H), 7.03 (d, J = 1.6 Hz, 1H), 6.89−6.87 (m, 1H), 5.99
(s, 2H), 3.90 (s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 160.3,
148.1, 147.3, 143.1, 142.8, 141.1, 135.5, 128.7, 127.5, 127.3, 120.8,
118.6, 111.5, 111.4, 108.5, 107.8, 101.2, 55.4, 29.7; IR (neat, cm−1):
2919, 2851, 2361, 1624, 1580, 1541, 1500, 1419, 1383, 1067, 1040,
799, 763, 668; HRMS (ESI) calcd for C20H16O3 ([M + H]+) 305.1172,
found 305.1176.
2H), 7.44−7.40 (m, 2H), 7.37−7.33 (m, 1H), 7.28−7.22 (m, 4H),
7.15 (d, J = 2.0 Hz, 1H), 6.98 (d, J = 2.0 Hz, 1H), 3.98 (s, 3H), 2.41
(s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 158.6, 148.9, 142.3,
141.6, 140.2, 137.3, 129.2, 128.8, 128.6, 127.8, 127.1, 121.7, 108.2,
90.2, 56.7, 56.7, 21.3; IR (neat, cm−1): 2922, 2851, 1558, 1513, 1497,
1458, 1430, 1390, 1228, 1139, 1037, 1015, 849, 818, 762, 698, 578;
HRMS (ESI) calcd for C20H17IO ([M + H]+) 401.0397, found
401.0399.
3-Methoxy-5-propyl-1,1′-biphenyl (2l): yield 39%; colorless oil; 1H
NMR (400 MHz, CDCl3) δ 7.52−7.50 (m, 2H), 7.35 (t, J = 8.0 Hz,
2H), 7.26 (t, J = 7.2 Hz, 1H), 6.93 (s, 1H), 6.87 (s, 1H), 6.66 (s, 1H),
3.78 (s, 3H), 2.55 (t, J = 7.6 Hz, 2H), 1.66−1.57 (m, 2H), 0.90 (t, J =
7.6 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 159.9, 144.7,
142.5, 141.4, 128.7, 127.3, 127.2, 120.1, 113.1, 110.0, 55.3, 38.3, 24.5,
13.9; IR (neat, cm−1): 2923, 2867, 1596, 1460, 1422, 1382, 1215,
1157, 1057, 847, 762, 699; HRMS (ESI) calcd for C16H18O ([M +
H]+) 227.1430, found 227.1430.
5′-Methoxy-4-methyl-1,1′:3′,1″-terphenyl (2m): yield 78%; yellow
oil; 1H NMR (400 MHz, CDCl3) δ 7.54 (d, J = 7.6 Hz, 2H), 7.45 (d, J
= 8.0 Hz, 2H), 7.35 (t, J = 7.6 Hz, 2H), 7.30−7.25 (m, 2H), 7.16 (d, J
= 7.6 Hz, 2H), 7.01 (s, 2H), 3.81 (s, 3H), 2.31 (s, 3H); 13C NMR
(100 MHz, CDCl3) δ (ppm) 160.3, 143.1, 143.1, 141.2, 138.2, 137.3,
129.5, 128.7, 127.5, 127.3, 127.1, 118.7, 111.6, 111.5, 55.4, 21.1; IR
(neat, cm−1): 2921, 1595, 1515, 1457, 1420, 1388, 1206, 1174, 1072,
1023, 869, 815, 762, 699; HRMS (ESI) calcd for C20H18O ([M + H]+)
275.1430, found 275.1432.
4-Chloro-5′-methoxy-1,1′:3′,1″-terphenyl (2n): yield 78%; color-
less oil; 1H NMR (400 MHz, CDCl3) δ 7.62 (d, J = 7.6 Hz, 2H), 7.56
(d, J = 8.4 Hz, 2H), 7.47−7.34 (m, 6H), 7.11 (s, 1H), 7.06 (d, J = 1.6
Hz, 1H), 3.91 (s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 160.4,
143.4, 141.9, 141.0, 139.6, 133.7, 128.9, 128.8, 128.5, 127.7, 127.3,
118.7, 112.0, 111.7, 55.5; IR (neat, cm−1): 2924, 2853, 1596, 1496,
1460, 1383, 1207, 1098, 1071, 1021, 824, 761, 699; HRMS (ESI) calcd
for C19H15ClO ([M + H]+) 295.0884, found 295.0884.
6′-Iodo-4,5′-dimethoxy-1,1′:3′,1″-terphenyl (4c): yield 72%; yel-
low oil; 1H NMR (400 MHz, CDCl3) δ 7.64−7.59 (m, 2H), 7.43 (t, J
= 7.6 Hz, 2H), 7.37 (d, J = 7.6 Hz, 1H), 7.34−7.30 (m, 2H), 7.16 (d,
2.0 Hz, 1H) 6.99−6.94 (m, 3H), 3.99 (s, 3H), 3.86 (s, 3H); 13C NMR
(100 MHz, CDCl3) δ (ppm) 159.1, 158.6, 148.5, 142.3, 140.2, 137.0,
130.5, 128.9, 127.8, 127.1, 126.9, 121.8, 113.3, 113.2, 108.1, 90.6, 56.7,
55.3; IR (neat, cm−1): 2930, 2834, 1608, 1557, 1511, 1462, 1430,
1389, 1245, 1140, 1032, 888, 830, 762, 697, 560; HRMS (ESI) calcd
for C20H17IO2 ([M + H]+) 417.0346, found 417.0350.
6′-Iodo-3,5′-dimethoxy-1,1′:3′,1″-terphenyl (4d): yield 55%;
yellow oil; 1H NMR (400 MHz, CDCl3) δ 7.60 (d, J = 6.2 Hz,
2H), 7.43 (t, J = 8.0 Hz, 2H), 7.35 (q, J = 7.6 Hz, 2H), 7.17 (d, J = 1.6
Hz, 1H), 7.00 (d, J = 1.6 Hz, 1H), 6.97−6.92 (m, 3H), 3.99 (s, 3H),
3.84 (s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 159.0, 158.6,
148.7, 145.7, 142.3, 140.1, 128.9, 128.9, 127.8, 127.1, 121.5, 114.9,
113.3, 108.3, 89.8, 56.7, 56.7, 55.3, 55.3; IR (neat, cm−1): 2921, 2850,
1582, 1560, 1489, 1458, 1427, 1387, 1215, 1031, 856, 762, 699, 588;
HRMS (ESI) calcd for C20H17IO2 ([M + H]+) 417.0346, found
417.0354.
4-Chloro-6′-iodo-5′-methoxy-1,1′:3′,1″-terphenyl (4f): yield 70%;
1
white oil; H NMR (400 MHz, CDCl3) δ 7.61−7.58 (m, 2H), 7.46−
7.38 (m, 5H), 7.31 (d, J = 8.8 Hz, 2H), 7.12 (d, J = 2.0 Hz, 1H), 7.01
(d, J = 2.0 Hz, 1H), 4.00 (s, 3H); 13C NMR (100 MHz, CDCl3) δ
(ppm) 158.7, 147.7, 142.8, 142.5, 140.0, 133.7, 130.7, 128.9, 128.2,
128.0, 127.1, 121.5, 108.6, 89.8, 56.7; IR (neat, cm−1): 2920, 2850,
1579, 1557, 1491, 1459, 1430, 1385, 1228, 1089, 1014, 829, 762, 698;
HRMS (ESI) calcd for C19H14ClIO ([M + H]+) 420.9851, found
420.9851.
4,5′-Dimethoxy-4″-methyl-1,1′:3′,1″-terphenyl (2o): yield 81%;
white solid; mp 97−99 °C; 1H NMR (400 MHz, CDCl3) δ 7.46 (dd, J
= 14.0 Hz, 8.0 Hz, 4H), 7.25 (s, 1H), 7.16 (d, J = 7.6 Hz, 2H), 6.96 (s,
2H), 6.89 (d, J = 8.4 Hz, 2H), 3.80 (s, 3H), 3.74 (s, 3H), 2.30 (s, 3H);
13C NMR (100 MHz, CDCl3) δ (ppm) 160.3, 159.3, 143.0, 142.7,
138.3, 137.3, 133.7, 129.4, 128.3, 127.1, 118.3, 114.2, 111.1, 111.0,
55.4, 55.4, 55.3, 55.3, 21.1, 21.1; IR (neat, cm−1): 2922, 2836, 1593,
1511, 1451, 1389, 1248, 1204, 1174, 1070, 1027, 812, 697; HRMS
(ESI) calcd for C21H20O ([M + H]+) 305.1536, found 305.1540.
4-Chloro-4″,5′-dimethoxy-1,1′:3′,1″-terphenyl (2p): yield 62%;
3-Chloro-6′-iodo-5′-methoxy-1,1′:3′,1″-terphenyl (4g): yield 65%;
yellow oil; 1H NMR (400 MHz, CDCl3) δ 7.61−7.59 (m, 2H), 7.44 (t,
J = 7.6 Hz, 2H), 7.39−7.36 (m, 4H), 7.27−7.25 (m, 1H), 7.12 (d, J =
2.0 Hz, 1H), 7.01 (s, J = 2.0 Hz, 1H), 4.00 (s, 3H); 13C NMR (100
MHz, CDCl3) δ (ppm) 158.7, 147.4, 146.0, 142.6, 140.0, 133.7, 129.4,
129.2, 128.9, 128.0, 127.7, 127.7, 127.1, 121.4, 108.7, 89.6, 56.7; IR
(neat, cm−1): 2919, 2850, 1561, 1458, 1431, 1386, 1146, 1073, 1039,
853, 786, 762, 697; HRMS (ESI) calcd for C19H14ClIO ([M + H]+)
420.9851, found 420.9849.
1
white solid; mp 99−101 °C; H NMR (400 MHz, CDCl3) δ 7.48
(dd, J = 8.8 Hz, 2.0 Hz, 4H), 7.34 (d, J = 8.8 Hz, 2H), 7.23 (d, J = 1.2
Hz, 1H), 7.00 (t, J = 2.0 Hz, 1H), 6.95−6.90 (m, 3H), 3.83 (s, 3H),
3.78 (s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 160.4, 159.4,
142.9, 141.8, 139.6, 133.6, 133.4, 128.9, 128.5, 128.3, 118.3, 114.2,
111.6, 111.0, 55.4, 55.3; IR (neat, cm−1): 2921, 2852, 1593, 1512,
1454, 1384, 1256, 1206, 1175, 1092, 1029, 821, 698; HRMS (ESI)
calcd for C20H17ClO2 ([M + H]+) 325.0990, found 325.0994.
5′,5‴-Dimethoxy-1,1′:3′,1″:4″,1‴:3‴,1‴′-quinquephenyl (2r):
2-(4-Iodo-5-methoxy-[1,1′-biphenyl]-3-yl)thiophene (4h): yield
1
35%; yellow oil; H NMR (400 MHz, CDCl3) δ 7.49 (d, J = 8.4
Hz, 2H), 7.36−7.32 (m, 2H), 7.29−7.25 (m, 2H), 7.20 (d, J = 2.0 Hz,
1H), 7.13−7.10 (m, 1H), 7.02−7.00 (m, 1H), 6.91 (s, 1H), 3.88 (s,
3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 158.9, 145.2, 142.3,
141.6, 139.9, 128.9, 127.9, 127.8, 127.1, 126.7, 125.7, 122.9, 109.1,
91.3, 56.8; IR (neat, cm−1): 2922, 2851, 1559, 1458, 1387, 1261, 1115,
1088, 1029, 851, 801, 760, 696; HRMS (ESI) calcd for C17H13IOS
([M + H]+) 392.9805, found 392.9812.
1
yield 30%; white oil; H NMR (400 MHz, CDCl3) δ 7.73 (s, 4H),
7.67−7.65 (m, 4H), 7.49−7.45 (m, 6H), 7.40−7.36 (m, 2H), 7.17 (t, J
= 2.0 Hz, 2H), 7.13 (t, J = 2.0 Hz, 2H), 3.94 (s, 6H); 13C NMR (100
MHz, CDCl3) δ (ppm) 160.4, 143.3, 142.6, 141.1, 140.3, 128.8, 127.7,
127.6, 127.3, 118.8, 111.9, 111.7, 55.5 IR (neat, cm−1): 2922, 2853,
1593, 1461, 1383, 1207, 1070, 1024, 828, 762, 699; HRMS (ESI) calcd
for C32H26O ([M + H]+) 443.2006, found 443.2010.
2-(4-Iodo-5-methoxy-[1,1′-biphenyl]-3-yl)furan (4i): yield 45%;
yellow oil; 1H NMR (400 MHz, CDCl3) δ 7.63−7.60 (m, 2H), 7.54−
7.49 (m, 1H), 7.48−7.43 (m, 3H), 7.39−7.20 (m, 1H) 7.07−6.98 (m,
2H), 6.54−6.48 (m, 1H), [3.98 (s), 3.90 (s), 3H]; 13C NMR (100
MHz, CDCl3) δ (ppm) 158.9, 153.9, 142.6, 142.2, 140.1, 137.6, 128.9,
128.7, 127.9, 127.2, 127.1, 121.2, 111.0, 110.2, 108.9, 86.9, 56.8; IR
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(neat, cm−1): 2921, 2852, 1553, 1495, 1459, 1389, 1227, 1136, 1085,
1036, 878, 808, 761, 697, 593; HRMS (ESI) calcd for C17H13IO2 ([M
+ H]+) 377.0033, found 377.0040.
7.13 (m, 1H), 7.03 (d, J = 1.6 Hz, 2H), [4.02 (s), 3.98 (s), 6H]; 13C
NMR (100 MHz, CDCl3) δ (ppm) 158.7, 148.6, 143.7, 142.4, 140.2,
128.9, 128.9, 128.8, 127.9, 127.3, 127.1, 121.7, 108.4, 90.0, 56.8; IR
(neat, cm−1): 2923, 1592, 1459, 1384, 1151, 1069, 1021, 832, 762, 698,
576; HRMS (ESI) calcd for C32H24I2O2 ([M + H]+) 694.9938, found
694.9944.
5-(4-Iodo-5-methoxy-[1,1′-biphenyl]-3-yl)benzo[d][1,3]dioxole
(4j): yield 58%; white oil; 1H NMR (400 MHz, CDCl3) δ 7.59 (d, J =
7.2 Hz, 2H), 7.45−7.42 (m, 2H), 7.39−7.35 (m, 1H), 7.14 (d, J = 2.0
Hz, 1H), 6.98 (d, J = 2.0 Hz, 1H), 6.88−6.86 (m, 2H), 6.82 (dd, J =
8.0 Hz, 2.0 Hz, 1H), 6.02 (s, 2H), 3.99 (s, 3H); 13C NMR (100 MHz,
CDCl3) δ (ppm) 158.7, 148.5, 147.0, 142.3, 140.2, 138.5, 128.9, 127.9,
127.1, 122.9, 121.7, 110.1, 108.3, 107.9, 101.1, 90.5, 56.7; IR (neat,
cm−1): 2922, 1558, 1494, 1454, 1390, 1243, 1220, 1093, 1037, 934,
854, 812, 762, 697, 660; HRMS (ESI) calcd for C20H15IO3 ([M +
H]+) 431.0139, found 431.0141.
(E)-4-Iodo-3-methoxy-5-styryl-1,1′-biphenyl (4k): yield 62%; light
yellow solid; mp 150−152 °C; 1H NMR (400 MHz, CDCl3) δ 7.64−
7.62 (m, 2H), 7.57 (d, J = 7.6 Hz, 2H), 7.51−7.45 (m, 4H), 7.41−7.36
(m, 3H), 7.31−7.29 (m, 1H), 7.02 (d, J = 16 Hz, 1H), 6.91 (d, J = 1.6
Hz, 1H), 3.96 (s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 158.6,
142.6, 142.4, 140.5, 136.9, 133.0, 132.0, 128.9, 128.7, 128.1, 127.8,
127.1, 126.9, 118.0, 108.7, 91.5, 56.7; IR (neat, cm−1): 2920, 1580,
1548, 1448, 1384, 1075, 760, 695, 603; HRMS (ESI) calcd for
C21H17IO ([M + H]+) 413.0397, found 413.0402.
4-Iodo-3-methoxy-5-propyl-1,1′-biphenyl (4l): yield 51%; yellow
oil; 1H NMR (400 MHz, CDCl3) δ 7.50 (d, J = 8.0 Hz, 2H), 7.36 (t, J
= 8.0 Hz, 2H), 7.31−7.27 (m, 1H), 6.99 (s, 1H), 6.76 (s, 1H), 3.86 (s,
3H), 2.76−2.72 (m, 2H), 1.65−1.55 (m, 2H), 0.95 (t, J = 7.2 Hz, 3H);
13C NMR (100 MHz, CDCl3) δ (ppm) 158.4, 147.4, 142.2, 140.6,
128.8, 127.6, 127.1, 121.0, 107.3, 91.7, 56.6, 43.3, 23.4, 13.9; IR (neat,
cm−1): 2923, 2855, 1560, 1455, 1392, 1223, 1076, 848, 761, 697, 610;
HRMS (ESI) calcd for C16H17IO ([M + H]+) 353.0397, found
353.0395.
Characterization Data of 5a−q. 4′,5′-Diiodo-1,1′:3′,1″-ter-
1
phenyl (5a): yield 70%; yellow oil; H NMR (400 MHz, CDCl3) δ
8.04 (d, J = 2.0 Hz, 1H), 7.47 (d, J = 7.2 Hz, 2H), 7.37−7.28 (m, 7H),
7.23 (d, J = 6.4 Hz, 2H); 13C NMR (100 MHz, CDCl3) δ (ppm)
149.8, 146.6, 142.4, 138.4, 136.9, 129.0, 128.9, 128.2, 128.0, 127.9,
127.4, 126.9, 111.0, 110.7; IR (neat, cm−1): 2922, 1576, 1530, 1493,
1446, 878, 757, 670, 573; HRMS (ESI) calcd for C18H12I2 ([M + H]+)
481.9023, found 481.9032.
5′,6′-Diiodo-4-methyl-1,1′:3′,1″-terphenyl (5b): yield 52%; yellow
oil; 1H NMR (400 MHz, CDCl3) δ 8.09−8.08 (m, 1H), 7.53 (dd, J =
7.2 Hz, 1.2 Hz, 2H), 7.43−7.34 (m, 4H), 7.25−7.19 (m, 4H), 2.42 (d,
1.6 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 149.8, 143.8,
142.4, 138.5, 137.7, 136.8, 129.0, 128.8, 128.7, 128.1, 127.4, 126.9,
111.3, 110.6, 21.3; IR (neat, cm−1): 2920, 2852, 1575, 1534, 1505,
1447, 1385, 878, 817, 762, 695, 571; HRMS (ESI) calcd for C19H14I2
([M + H]+) 495.9179, found 495.9185.
5′,6′-Diiodo-2,5-dimethoxy-1,1′:3′,1″-terphenyl (5e): yield 20%;
white colorless oil; 1H NMR (400 MHz, CDCl3) δ 8.09 (d, J = 1.6 Hz,
1H), 7.56−7.54 (m, 2H), 7.43−7.34 (m, 4H), 6.93−6.87 (m, 2H),
6.69 (d, J = 2.4 Hz, 1H), 3.78 (dd, J = 13.2 Hz, 6.4 Hz, 6H); 13C NMR
(100 MHz, CDCl3) δ (ppm) 153.2, 150.2, 146.7, 142.4, 138.6, 136.8,
136.2, 128.9, 128.1, 127.8, 127.0, 116.1, 114.3, 112.2, 56.2, 55.8; IR
(neat, cm−1): 2922, 2853, 1593, 1457, 1382, 1211, 1165, 1068, 853,
760, 696, 613; HRMS (ESI) calcd for C20H16I2O2 ([M + H]+)
542.9312, found 542.9310.
4′-Iodo-5′-methoxy-4-methyl-1,1′:3′,1″-terphenyl (4m): yield
4-Chloro-5′,6′-diiodo-1,1′:3′,1″-terphenyl (5f): yield 63%; white
oil; 1H NMR (400 MHz, CDCl3) δ 8.11 (d, J = 1.6 Hz, 1H), 7.53 (d, J
= 7.2 Hz, 2H), 7.44−7.36 (m, 6H), 7.24 (d, J = 8.0 Hz, 2H); 13C
NMR (100 MHz, CDCl3) δ (ppm) 148.5, 144.8, 142.6, 138.3, 137.2,
134.0, 130.3, 129.0, 128.3, 126.9, 110.9, 110.8; IR (neat, cm−1): 2922,
2865, 2361, 1665, 1599, 1463, 1384, 811, 763, 684, 658, 649; HRMS
(ESI) calcd for C18H11ClI2 ([M + H]+) 515.8633, found 515.8639.
2-(4,5-Diiodo-[1,1′-biphenyl]-3-yl)thiophene (5h): yield 20%;
1
47%; light yellow oil; H NMR (400 MHz, CDCl3) δ 7.42 (d, J =
8.0 Hz, 2H), 7.39−7.28 (m, 5H), 7.17−7.15 (m, 2H), 7.07 (d, J = 2.0
Hz, 1H), 6.91 (s, 1H), 3.91 (s, 3H), 2.31 (s, 3H); 13C NMR (100
MHz, CDCl3) δ (ppm) 158.6, 148.8, 144.6, 142.3, 137.7, 137.3, 129.6,
129.3, 127.9, 127.6, 126.9, 121.4, 108.2, 89.6, 56.7, 21.1; IR (neat,
cm−1): 2920, 1556, 1513, 1453, 1384, 1141, 1090, 1020, 813, 764, 700,
558; HRMS (ESI) calcd for C20H17IO ([M + H]+) 401.0397, found
401.0399.
4-Chloro-4′-iodo-5′-methoxy-1,1′:3′,1″-terphenyl (4n): yield 35%;
yellow oil; 1H NMR (400 MHz, CDCl3) δ 7.55−7.51 (m, 2H), 7.46−
7.35 (m, 7H), 7.11 (d, J = 1.6 Hz, 1H), 6.95 (d, J = 1.6 Hz, 1H), 3.99
(s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 158.8, 149.1, 144.3,
141.1, 138.6, 134.0, 129.3, 129.0, 128.3, 127.9, 127.7, 121.4, 108.0,
90.5, 56.8, 56.7; IR (neat, cm−1): 2911, 1558, 1447, 1382, 1082, 1016,
822, 759, 700; HRMS (ESI) calcd for C19H14ClIO ([M + H]+)
420.9851, found 420.9853.
4′-Iodo-4″,5′-dimethoxy-4-methyl-1,1′:3′,1″-terphenyl (4o): yield
45%; colorless oil; 1H NMR (400 MHz, CDCl3) δ 7.41 (d, J = 8.0 Hz,
2H), 7.24−7.21 (m, 2H), 7.16−7.14 (m, 2H), 7.06 (d, J = 2.0 Hz,
1H), 6.88 (dd, J = 6.4 Hz, 2.0 Hz, 3H), 3.89 (s, 3H), 3.77 (s, 3H), 2.30
(s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 159.0, 158.6, 148.4,
142.2, 137.7, 137.3, 137.1, 130.5, 129.6, 126.9, 121.6, 113.2, 108.0,
90.1, 56.7, 56.7, 55.3, 55.2, 21.1, 21.1 IR (neat, cm−1): 2924, 1609,
1555, 1511, 1459, 1385, 1245, 1177, 1140, 1087, 1026, 908, 813, 731,
583; HRMS (ESI) calcd for C21H19IO2 ([M + H]+) 431.0502, found
431.0502.
1
white oil; H NMR (400 MHz, CDCl3) δ 8.11 (d, J = 2.0 Hz, 1H),
7.55−7.53 (m, 3H), 7.45−7.36 (m, 4H), 7.12−7.08 (m, 2H); 13C
NMR (100 MHz, CDCl3) δ (ppm) 147.3, 142.3, 138.2, 137.6, 129.0,
128.8, 128.3, 127.8, 127.0, 126.6, 125.8, 112.6, 110.8; IR (neat, cm−1):
2921, 2852, 1578, 1540, 1462, 1382, 1155, 1068, 762, 698; HRMS
(ESI) calcd for C16H10I2S ([M + H]+) 488.8665, found 488.8666.
5-(4,5-Diiodo-[1,1′-biphenyl]-3-yl)benzo[d][1,3]dioxole (5j): yield
55%; light yellow solid; mp 53−55 °C; 1H NMR (400 MHz, CDCl3) δ
8.08 (d, J = 2.4 Hz, 1H), 7.55−7.53 (m, 2H), 7.44−7.34 (m, 4H), 6.85
(d, J = 8.0 Hz, 1H), 6.78−6.73 (m, 2H), 6.01 (s, 2H); 13C NMR (100
MHz, CDCl3) δ (ppm) 149.3, 147.3, 147.0, 142.4, 140.5, 138.4, 136.9,
129.0, 128.2, 127.5, 126.9, 122.5, 111.6, 110.5, 109.7, 107.9, 101.2; IR
(neat, cm−1): 2921, 1489, 1439, 1387, 1226, 1038, 937, 907, 813, 734,
697, 647, 565; HRMS (ESI) calcd for C19H12I2O2 ([M + H]+)
526.8999, found 526.8999.
(E)-3,4-Diiodo-5-styryl-1,1′-biphenyl (5k): yield 74%; white solid;
mp 150−152 °C; 1H NMR (400 MHz, CDCl3) δ 8.02 (d, J = 2.0 Hz,
1H), 7.68 (d, J = 2.0 Hz, 1H), 7.55 (t, J = 8.8 Hz, 4H), 7.46−7.36 (m,
6H), 7.29 (t, J = 7.2 Hz, 1H), 6.87 (d, J = 16.0 Hz, 1H); 13C NMR
(100 MHz, CDCl3) δ (ppm) 144.2, 142.9, 138.8, 137.0, 136.4, 135.7,
132.9, 129.0, 128.8, 128.3, 128.2, 127.0, 126.9, 124.3, 111.8, 111.0; IR
(neat, cm−1): 2919, 1519, 1382, 1072, 1026, 952, 872, 763, 693, 545;
HRMS (ESI) calcd for C20H14I2 ([M + H]+) 507.9179, found
507.9189.
4-Chloro-4′-iodo-4″,5′-dimethoxy-1,1′:3′,1″-terphenyl (4p): yield
1
57%; white oil; H NMR (400 MHz, CDCl3) δ 7.45 (d, J = 8.4 Hz,
2H), 7.34−7.31 (m, 2H), 7.22 (d, J = 8.8 Hz, 2H), 7.03 (d, J = 1.6 Hz,
1H), 6.89 (d, J = 8.8 Hz, 2H), 6.85 (d, J = 2.0 Hz, 1H), 3.91 (s, 3H),
3.79 (s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 159.1, 158.8,
148.7, 141.0, 138.7, 136.9, 133.9, 130.5, 129.0, 128.3, 121.6, 113.3,
107.8, 91.0, 56.7, 55.3; IR (neat, cm−1): 2922, 1609, 1512, 1460, 1382,
1246, 1141, 1092, 1023, 887, 824, 707, 582; HRMS (ESI) calcd for
C20H16ClIO2 ([M + H]+) 450.9956, found 450.9957.
4′,5′-Diiodo-4-methyl-1,1′:3′,1″-terphenyl (5m): yield 12%; color-
1
less oil; H NMR (400 MHz, CDCl3) δ 8.09 (d, J = 2.0 Hz, 1H),
7.44−7.38 (m, 6H), 7.29 (d, J = 8.0 Hz, 2H), 7.22 (d, J = 8.0 Hz, 2H),
2.37 (s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 149.7, 146.6,
142.3, 138.1, 136.7, 135.5, 129.7, 128.9, 128.0, 127.9, 127.2, 126.7,
110.6, 110.6, 21.1; IR (neat, cm−1): 2919, 1361, 1512, 1386, 1025, 815,
4′,6‴-Diiodo-5′,5‴-dimethoxy-1,1′:3′,1″:4″,1‴:3‴,1‴′-quinque-
1
phenyl (4r): yield 27%; white oil; H NMR (400 MHz, CDCl3) δ
7.73−7.62 (m, 5H), 7.49−7.43 (m, 8H), 7.40−7.36 (m, 2H), 7.22−
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Article
764, 738, 699, 568; HRMS (ESI) calcd for C19H14I2 ([M + H]+)
495.9179, found 495.9188.
ACKNOWLEDGMENTS
■
Financial support was received from the National Science
Foundation (NSF 21072080), National Basic Research
Program of China (973 Program, 2010CB833203) and the
Fundamental Research Funds for the Central Universities
(lzujbky-2012-215).
4′,5′-Diiodo-4″-methoxy-4-methyl-1,1′:3′,1″-terphenyl (5o): yield
20%; colorless oil; 1H NMR (400 MHz, CDCl3) δ 8.06 (d, J = 2.4 Hz,
1H), 7.44−7.39 (m, 3H), 7.24−7.21 (m, 4H), 6.94 (d, J = 8.4 Hz,
2H), 3.85 (s, 3H), 2.37 (s, 3H); 13C NMR (100 MHz, CDCl3) δ
(ppm) 159.2, 149.4, 142.3, 139.3, 138.1, 136.5, 135.5, 130.1, 129.7,
127.3. 126.7, 113.3, 111.2, 110.5, 55.3, 55.3, 21.1; IR (neat, cm−1):
2920, 1609, 1509, 1384, 1247, 1034, 905, 814, 732, 573; HRMS (ESI)
calcd for C20H16I2O ([M + H]+) 526.9363, found 526.9363.
1-(4,5-Diiodo-[1,1′-biphenyl]-3-yl)naphthalene (5q): yield 43%;
white solid; mp 54−56 °C; 1H NMR (400 MHz, CDCl3) δ 8.20 (d, J
= 2.0 Hz, 1H), 7.91 (d, J = 8.4 Hz, 2H), 7.57−7.48 (m, 6H), 7.45−
7.31 (m, 5H); 13C NMR (100 MHz, CDCl3) δ (ppm) 148.3, 144.3,
142.4, 138.3, 137.1, 133.5, 131.0, 129.0, 128.4, 128.3, 128.2, 128.2,
126.9, 126.5, 126.4, 126.1, 125.8, 125.2, 112.6, 110.4; IR (neat, cm−1):
2922, 2852, 1530, 1389, 1074, 1026, 906, 879, 768, 731, 695, 583;
HRMS (ESI) calcd for C22H14I2 ([M + H]+) 531.9179, found
531.9191.
REFERENCES
■
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1
1,1′:3′,1″-terphenyl (2aa): yield 25%; colorless oil; H NMR (400
MHz, CDCl3) δ 7.65−7.63 (m, 4H), 7.45 (t, J = 7.6 Hz, 4H), 7.39−
7.35 (m, 3H), 7.11 (d, J = 1.2 Hz, 2H), 4.16 (q, J = 6.8 Hz, 2H), 1.47
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cm−1): 2922, 2853, 1596, 1461, 1383, 1195, 1069, 1044, 868, 759, 698;
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275.1435.
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1
oil; H NMR (400 MHz, CDCl3) δ 7.60−7.58 (m, 2H), 7.46−7.36
(m, 8H), 7.15 (d, J = 1.6 Hz, 1H), 6.98 (d, J = 1.6 Hz, 1H), 4.22 (q, J
= 6.8 Hz, 2H), 1.55 (t, J = 7.2 Hz, 3H); 13C NMR (100 MHz, CDCl3)
δ (ppm) 158.2, 148.9, 144.6, 142.2, 140.2, 129.3, 128.9, 128.7, 127.9,
127.8, 127.6, 127.3, 127.1, 121.5, 109.6, 90.9, 65.4, 14.9; IR (neat,
cm−1): 2924, 1558, 1495, 1448, 1389, 1228, 1138, 1043, 861, 761, 698,
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401.0398.
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5′-Methoxy-4′-(phenylethynyl)-1,1′:3′,1″-terphenyl (4ab): yield
1
65%; yellow oil; H NMR (400 MHz, CDCl3) δ 7.62 (d, J = 7.2
Hz, 2H), 7.58−7.56 (m, 2H), 7.40−7.36 (m, 4H), 7.34−7.29 (m, 2H),
7.27−7.25 (m, 2H), 7.21−7.16 (m, 4H), 7.04 (d, J = 1.6 Hz, 1H), 3.95
(s, 3H); 13C NMR (100 MHz, CDCl3) δ (ppm) 160.8, 146.1, 142.2,
140.6, 140.5, 131.3, 129.5, 128.8, 128.1, 127.9, 127.8, 127.6, 127.2,
123.8, 120.9, 110.2, 108.1, 97.4, 85.5, 56.2, 56.2; IR (neat, cm−1):
3057, 1594, 1552, 1492, 1458, 1404, 1344, 1021, 758, 696; HRMS
(ESI) calcd for C27H20O ([M + H]+) 361.1587, found 361.1594.
4′,5′-Bis(phenylethynyl)-1,1′:3′,1″-terphenyl (5ab): yield 96%; red
́
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1
oil; H NMR (400 MHz, CDCl3) δ 7.83 (d, J = 2.0 Hz, 1H), 7.73−
7.71 (m, 2H), 7.66 (d, J = 7.2 Hz, 2H), 7.63−7.61 (m, 3H), 7.51−7.43
(m, 5H), 7.38−7.34 (m, 6H), 7.27 (dd, J = 5.2 Hz, 1.6 Hz, 3H); 13C
NMR (100 MHz, CDCl3) δ (ppm) 144.8, 140.7, 140.4, 139.5, 131.7,
131.4, 129.4, 129.2, 128.9, 128.5, 128.4, 128.3, 128.0, 128.0, 128.0,
127.8, 127.2, 127.1, 127.0, 123.5, 123.3, 123.0, 97.3, 93.5, 88.8, 88.2; IR
(neat, cm−1): 3057, 2921, 1595, 1542, 1492, 1384, 1069, 1025, 911,
756, 694, 595; HRMS (ESI) calcd for C34H22 ([M]+) 430.1716, found
430.1729.
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ASSOCIATED CONTENT
* Supporting Information
■
(8) (a) Ji, K.-G.; Zhu, H.-T.; Yang, F.; Shaukat, A.; Xia, X.-F.; Yang,
Y.-F.; Liu, X.-Y.; Liang, Y.-M. J. Org. Chem. 2010, 75, 5670. (b) Ji, K.-
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2010, 16, 6151. (d) Zhu, H.-T.; Ji, K.-G.; Yang, F.; Wang, L.-J.; Zhao,
S.-C.; Shaukat, A.; Liu, X.-Y.; Liang, Y.-M. Org. Lett. 2011, 13, 684.
(e) Shaukat, A.; Zhu, H.-T.; Xia, X.-F.; Ji, K.-G.; Yang, Y.-F.; Song, X.-
R.; Liang, Y.-M. Org. Lett. 2011, 13, 2598. (f) Shaukat, A.; Li, Y.-X.;
Saeed, A.; Yang, F.; Chen, Z.-S.; Liang, Y.-M. J. Org. Chem. 2012, 77,
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S
Text giving additional experimental details and figures giving
analytical data for all new compounds. This material is available
free of charge via the Internet at http://pubs.acs.org.
AUTHOR INFORMATION
Corresponding Author
*E-mail: liangym@lzu.edu.cn.
■
Notes
The authors declare no competing financial interest.
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MeOH at room temperature was also likely to generate intermediate
7a with a fast conversion rate, which could not be observed by TLC
and isolated for high activity. Therefore, we considered it as a potential
path with 7a as an intermediate.
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