Cu(I)-catalyzed coupling of diaryldiazomethanes with terminal alkynes: An efficient synthesis of tri-aryl-substituted allenes

Article abstract of DOI:10.1016/j.tet.2015.10.043

A highly efficient method for the synthesis of tri-aryl-substituted allenes has been developed through Cu(I)-catalyzed coupling of diaryldiazomethanes with terminal alkynes. The reaction is under mild conditions and uses simple and inexpensive CuI as the catalyst. Mechanistically, the reaction follows a pathway involving Cu(I) carbene migratory insertion.

Full text of DOI:10.1016/j.tet.2015.10.043

Accepted Manuscript
Cu(I)-Catalyzed Coupling of Diaryldiazomethanes with Terminal Alkynes: An Efficient
Synthesis of Tri-Aryl-Substituted Allenes
Chenggui Wu, Fangdong Hu, Zhenxing Liu, Guisheng Deng, Fei Ye, Yan Zhang,
Jianbo Wang
PII:
S0040-4020(15)30143-5
10.1016/j.tet.2015.10.043
TET 27215
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 3 September 2015
Revised Date: 14 October 2015
Accepted Date: 16 October 2015
Please cite this article as: Wu C, Hu F, Liu Z, Deng G, Ye F, Zhang Y, Wang J, Cu(I)-Catalyzed
Coupling of Diaryldiazomethanes with Terminal Alkynes: An Efficient Synthesis of Tri-Aryl-Substituted
Allenes, Tetrahedron (2015), doi: 10.1016/j.tet.2015.10.043.
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Cu(I)-Catalyzed Coupling of Diaryldiazomethanes
with Terminal Alkynes: An Efficient Synthesis
of Tri-Aryl-Substituted Allenes
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Chenggui Wu, Fangdong Hu, Zhenxing Liu, Guisheng Deng,* Fei Ye, Yan Zhang and Jianbo Wang*

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Tetrahedron
journal homepage: www.elsevier.com
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Cu(I)-Catalyzed Coupling of Diaryldiazomethanes with Terminal Alkynes: An
Efficient Synthesis of Tri-Aryl-Substituted Allenes
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Chenggui Wu,a,b Fangdong Hu,b Zhenxing Liu,b Guisheng Deng,a,* Fei Ye,b Yan Zhangb and Jianbo
Wangb,*
aCollege of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, People’s Republic of China
bKey Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871,
People’s Republic of China
20 ARTICLE INFO
ABSTRACT
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A highly efficient method for the synthesis of tri-aryl-substituted allenes has been developed
through Cu(I)-catalyzed coupling of diaryldiazomethanes with terminal alkynes. The reaction is
under mild conditions and uses simple and inexpensive CuI as the catalyst. Mechanistically, the
reaction follows a pathway involving Cu(I) carbene migratory insertion.
Article history:
Received
Received in revised form
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Available online
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2009 Elsevier Ltd. All rights reserved.
Keywords:
Cross-Coupling
Diazo compounds
Allene
Terminal alkyne
Synthesis
1. Introduction
Scheme 1. Allene Synthesis through Cu(I) Carbene Migratory
Insertion
In recent years, the study of allenes has attracted considerable
attention due to their unique structural features and chemical
properties attributed to the presence of two perpendicular π
bonds.1 On one hand, allenes have been recognized as versatile
substrates or intermediates in modern organic synthesis,2 on the
other hand many natural products and pharmaceutically related
compounds bear allene structural units.3 Accordingly, the
methods for the synthesis of allenes have been studied
extensively over the past decades.4 One of the typical methods to
access allenes is the SN2'-type displacement of propargyl alcohol
derivatives with organocopper species.4,5 Up to now, the allene
synthesis by means of direct coupling has remained much less
48 developed with only few examples reported in the literature.6
Among the previously reported methods, the Crabbé
homologation is quite attractive.7 While the scope of the original
the Crabbé homologation is limited, recent extensive studies by
Ma and co-workers have significantly expanded this
methodology for allene synthesis.8
We have recently developed a method for allene synthesis
through Cu(I)-catalyzed cross-coupling reaction of N-
tosylhydrazones and terminal alkynes.9,10 This method is based on
a Cu(I) carbene migratory insertion process, which has been
extensively explored in our research group (Scheme 1A).11 Our
method can be applied to the synthesis of allenes of various
substitution patterns, however, its application to the synthesis of
tri-aryl-substituted allenes is less efficient. In our previous
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2
Tetrahedron
communication, we have only examined one example of the
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o
Cu(I)-catalyzed coupling for the synthesis of tri-phenyl-
substituted allene.9a The reaction is carried out under harsh
conditions and requires expensive ligand and the allene product
could only be obtained in 40% yield (Scheme 1B). To further
improve the allene synthesis based on the Cu(I) carbene
migratory insertions, we herein report an efficient method
towards the synthesis of tri-substituted aromatic allenes based on
copper(I)-catalyzed cross-coupling of diaryldiazomethanes with
terminal alkynes under mild conditions (Scheme 1C).
CuI (20 mol%), i-Pr2NH (1.1 equiv), 1,4-dioxane (1 mL), 30 C,
1 h.
With the optimized reaction conditions in hand, we then
explored
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the
scope
of
this
reaction
with
(diazomethylene)dibenzene 1a and various terminal alkynes 2a-k
(Scheme 2). The reactions afforded the corresponding products
in good yields under the optimized reaction conditions. It is
noteworthy that the reactions are not significantly affected by the
substituents on the aromatic moiety of the terminal alkynes (3b-
g). Heterocycle such as thiophene (3h) is also tolerated in the
reaction system. In addition, the reaction with alkyl terminal
alkynes also afforded the allene product in good yield. In
particular, the alkyl-substituted terminal alkyne bearing free
hydroxyl group (3i) can also be employed in this reaction.
2. Results and discussion
At the beginning of this investigation, Cu(I)-catalyzed
reaction of (diazomethylene)dibenzene 1a and phenylacetylene
2a was examined with copper(I) iodide as the catalyst, 1,4-
dioxane as the solvent and i-Pr2NH as the base at 30 oC (Table 1).
The characteristic violet color of diazo compound 1a of the
reaction system turned to a pale yellow solution in an hour,
which indicated the completion of the reaction. Upon work-up
and isolation by column chromatography, the desired allene
product 3a was obtained in 88% yield (entry 1). We have also
examined the effect of temperature and solvent, and found that
the yield was diminished with the raise of the temperature. Under
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Scheme 2. The Substrate Scope of Terminal Alkynesa
elevated temperature, significant amount of by-products 3aʹ and
3aʹʹ were observed (entries 2-3). In terms of the solvent, 1,4-
dioxane was found better than other solvents, such as THF,
toluene, MeCN, DCE, as it led to a clean reaction system (entry
4-7). Furthermore, we founded that the CuI and i-Pr2NH were
indispensable for the reaction (entries 8-9). However, the yield of
the product 3a could not be improved with the increase of the i-
Pr2NH. Instead, significant amount of the products derived from
the addition of i-Pr2NH to allene was observed in GC-MS (entry
10). The optimized reaction condition is summarized as follows:
under a nitrogen atmosphere, substrate ratio of 1a to 2a is 1 : 1,
Table 1. Optimization of the Reaction Conditionsa
aAll the reactions were set with (diazomethylene)dibenzene 1a
(0.2 mmol), alkyne 2a-k (1 equiv), CuI (20 mol%) and i-Pr2NH
(1.1 equiv) in dioxane (1 mL) under nitrogen atmosphere at 30 oC
for 1 h, bIsolated yield by column chromatography.
Entry CuI (mol%) iPr2NH (equiv) solvent T(oC) Yield(%)a
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20
--
1.1
1.1
1.1
1.1
1.1
1.1
1.1
1.1
--
dioxane 30
88
--c
--c
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80
75
trace
0
dioxane
dioxane
THF
toluene
DCE
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30
30
30
30
Next, the reaction scope was examined for a variety of
diaryldiazomethanes under the optimized reaction conditions
(Scheme 3). The reactions of a series of diaryldiazomethanes
with phenylacetylene 2a under the identical reaction conditions
afforded the corresponding allene products 4a-j in moderate to
good yields, except the case of the 2-(1-diazoethyl)naphthalene
(4i), in which the dimished yield is attributed to the instability of
the allene product at room temperature. For the
diaryldiazomethanes derived from the corresponding ketones, it
is noteworthy that the reactions were marginally affected by the
substituents on the aromatic ring (4a-h). Furthermore, we have
tried the reaction of substituted terminal alkynes and
diaryldiazomethanes 2c, d, i under the optimized reaction
conditions. The corresponding allene products (4j-m) were
obtained in good yields.
MeCN
dioxane 30
dioxane 30
dioxane 30
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20
0
70
10
2.2
aAll
the
reactions
were
carried
out
with
(diazomethylene)dibenzene 1a (0.2 mmol), phenylacetylene 2a
(0.2 mmol), CuI and i-Pr2NH in solvent (1 mL) under nitrogen
atmosphere at the indicated tenperature for 1 h. bIsolated yield by
c
column chromatography. The product was a mixture of 3a, 3aʹ
and 3aʹʹ. It was difficult to separate.

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Scheme 3. The Substrate Scope of Diaryldiazomethanesa
Except the gram-scale experiments, all the reactions were
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performed under nitrogen atmosphere in a 20 mL Schlenk tube.
For the gram-scale experiments, the reaction was carried out in
round-bottle flask. Dioxane was dried over Na before use. For
chromatographic purification, 200-300 mesh silica gel (Qingdao,
China) was employed. 1H NMR and 13C NMR spectra were
recorded on Varian 300 MHz and Brucker ARX 400 MHz
spectrometer in CDCl3 solution and the chemical shifts were
reported in parts per million (δ) relative to internal standard TMS
(0 ppm). Diaryldiazomethanes were prepared according to the
literature procedure.12 Unless otherwise noted, the materials
received from commercial suppliers were used without further
purifications.
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General Procedure for the Preparation of Diaryldiazomethanes
Step 1. Preparation of Diarylmethanone Hydrazone. Hydrazine
monohydrate (85% purity, 18.2 mL, 30 mmol) was added to a
solution of diarylmethanone (20 mmol) in ethanol (20 mL). Then,
aqueous HCl (36.0-38.0%, 0.5 mL) was added and the mixture
was heated to reflux for 12 hours. After cooling to room
temperature, the diarylmethanone hydrazone was precipitated as
white needle-shaped crystal. Filtration of the crude mixture gave
pure diarylmethanone hydrazone (82-94% yield) as white solid.
Step 2. Preparation of Diaryldiazomethane. A mixture of
diarylmethanone hydrazone (10 mmol, 1.0 equiv), anhydrous
o
MgSO4 (1 g) and 30 mL CH2Cl2 was cooled to 0 C. To this
rapidly stirring mixture was added activated MnO2 (3.04 g, 35
mmol, 3.5 equiv) in one portion. The reaction mixture was
warmed to room temperature and kept stirring for 8 hours, and
then the solid was filtered off with a Celite pad and washed with
CH2Cl2. After removal of the solvent under reduced pressure, the
residual was purified by silica gel (pretreated with petroleum
ether : Et3N = 10 : 1) with petroleum ether : Et3N = 20 : 1 as the
eluent to afford diaryldiazomethane as purple solid (72-85%
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yield). The diaryldiazomethanes can be kept at -20 C for weeks
without evident decomposition.
General Procedure for the CuI-Catalyzed Cross-Coupling of
Diaryldiazomethanes and Terminal Alkynes
Under nitrogen atmosphere, terminal alkyne (0.2 mmol) was
added to a mixture of CuI (8 mg, 0.04 mmol), i-Pr2NH (22 mg,
0.22 mmol) and diaryldiazomethane (0.2 mmol) in 1,4-dioxane
aAll the reactions were set with diaryldiazomethane 1 (0.2
mmol), alkyne 2 (1 equiv), CuI (20 mol%) and i-Pr2NH (1.1
equiv) in dioxane (1 mL) under nitrogen atmosphere at 30 oC for
1 h, b Isolated yield by column chromatography.
o
(1 mL). The solution was stirred at 30 C for 1 hour and the
progress of the reaction was monitored by TLC. Upon
completion of the reaction, the reaction mixture was cooled down
to room temperature and filtered through a short path of silica gel
by using EtOAc as the eluent. The solvent was removed in vacuo
to leave a crude mixture, which was purified by column
chromatography with silica gel to afford the pure allene product.
Finally, a scale-up experiment was carried out with 3 mmol
of 1d under the optimized reaction conditions, affording 0.89
gram of 4c (88%). The results demonstrate the practical
usefulness of this preparative method.
Propa-1,2-diene-1,1,3-triyltribenzene (3a).9a Following the
typical procedure above, the crude residue was purified by
column chromatography on silica gel (eluted with petroleum
3. Summary
In summary, we have developed an efficient approach
towards the synthesis of tri-aryl-substituted allenes from terminal
alkynes and diaryldiazomethanes via CuI-catalyzed cross-
coupling. The advantages of the method are: 1) the CuI catalyst is
cheap, and no ligand is necessary; 2) the reaction is easy to
operate with wide substrate scope at relatively low temperature;
3) the reactions are carried out with 1:1 ratio of the starting
materials. With these advantages, it is expected that this method
will find wide applications in organic synthesis.
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ether) to afford pure 3a as a yellow oil (47 mg, 88%); H NMR
(400 MHz, CDCl3) δ 7.30-7.35 (m, 6H), 7.16-7.26 (m, 8H), 7.09-
7.14 (m, 1H), 6.61(s, 1H); 13C NMR (100 MHz, CDCl3) δ 208.27,
136.13, 133.84, 128.78, 128.47, 128.44, 127.56, 127.36, 126.96,
113.71, 97.70.
(3-(4-Chlorophenyl)propa-1,2-diene-1,1-diyl)dibenzene
(3b).
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether) to afford pure 3b as a yellow oil (56 mg, 93%);
1H NMR (400 MHz, CDCl3) δ 7.38-7.41 (m, 3H), 7.25-7.36 (m,
11H), 6.65 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 208.30,
135.85, 132.94, 132.41, 128.95, 128.53, 128.42, 128.10, 127.72,
4. Experimental section
4.1 General

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114.11, 96.82; IR (film, cm-1) 1929, 1596, 1489, 1442, 1094,
135.56, 129.23 (q, J = 32.2 Hz), 128.61, 128.46, 127.90, 127.05,
1013; EI-MS (m/z, relative intensity) 302 (M+, 22), 267 (100),
252 (18), 207 (45), 165(39), 126 (20), 91(19); HRMS (ESI) calcd
for C21H16Cl [(M+H)+] 303.0935, found: 303.0935.
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(3-(4-Bromophenyl)propa-1,2-diene-1,1-diyl)dibenzene
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Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether) to afford pure 3c as a yellow oil (69 mg, 99%);
1H NMR (400 MHz, CDCl3) δ 7.29-7.33 (m, 6H), 7.23-7.35 (m,
8H), 6.65 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 208.33, 135.80,
132.92, 131.90, 128.54, 128.43, 127.74, 121.03, 114.17, 96.90
(one peak was missed because of overlap); IR (film, cm-1) 1930,
1597, 1458, 1442, 1070, 1009; EI-MS (m/z, relative intensity)
346 (M+, 21), 281 (18), 267 (25), 253 (12), 207 (100), 191 (29),
168 (72), 147 (29), 91 (45); HRMS (ESI) calcd for C21H16Br
[(M+H)+] 347.0430, found: 347.0430.
3-(3,3-Diphenylpropa-1,2-dien-1-yl)thiophene (3h). Following
the typical procedure above, the crude residue was purified by
column chromatography on silica gel (eluted with petroleum
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ether) to afford pure 3h as a yellow oil (38 mg, 69%); H NMR
(400 MHz, CDCl3) δ 7.34-7.42 (m, 4H), 7.32-7.36 (m, 4H), 7.24-
7.30 (m, 3H), 7.17-7.18 (m, 2H), 6.77 (s, 1H); 13C NMR (100
MHz, CDCl3) δ 208.42, 136.26, 135.08, 128.49, 128.46, 127.51,
126.29, 126.15, 127.50, 112.83, 92.17; IR (film, cm-1) 1935,
1957, 1491, 1442, 1073, 907; EI-MS (m/z, relative intensity) 274
(M+, 15), 256 (100), 241 (32), 226 (10), 207 (98), 191 (12), 178
(11), 165 (12), 152 (11), 141 (40), 128 (51), 113 (15), 102 (10);
HRMS (ESI) calcd for C19H15S [(M+H)+] 275.0889, found:
275.0889.
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(3-(m-Tolyl)propa-1,2-diene-1,1-diyl)dibenzene (3d). Following
the typical procedure above, the crude residue was purified by
column chromatography on silica gel (eluted with petroleum
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ether) to afford pure 3d as a yellow oil (55 mg, 98%); H NMR
5,5-Diphenylpenta-3,4-dien-2-ol (3i). Following the typical
procedure above, the crude residue was purified by column
chromatography on silica gel (eluted with petroleum ether : ethyl
acetate = 10 : 1 ) to afford pure 3i as a yellow oil (38 mg, 88%);
1H NMR (400 MHz, CDCl3) δ 7.17-7.29 (m, 10H), 5.74 (d, J =
5.6 Hz, 1H), 4.39-4.45 (m, 1H), 1.31 (d, J = 6.4 Hz, 3H); 13C
NMR (100 MHz, CDCl3) δ 203.22, 136.37, 128.40, 128.36,
127.42, 112.59, 100.01, 66.33, 23.52; IR (film, cm-1) 3373, 1944,
1597, 1492, 1451, 1073, 908; EI-MS (m/z, relative intensity) 236
(M+, 12), 218 (5), 207 (5), 193 (100), 178 (17), 165 (10), 152 (5),
115 (85), 91 (16); HRMS (ESI) calcd for C17H17O [(M+H)+]
237.1274, found: 237.1273.
(400 MHz, CDCl3) δ 7.33-7.36 (m, 4H), 7.17-7.27 (m, 6H), 7.10-
20 7.13 (m, 3H), 6.94-6.96 (m, 1H), 6.59 (s, 1H), 2.24 (s, 3H); 13C
NMR (100 MHz, CDCl3) δ 208.31, 138.43, 136.22, 133.73,
128.69, 128.46, 128.23, 127.60, 127.52, 124.15, 113.56, 97.25,
21.39 (one peak was missed because of overlap); IR (film, cm-1)
1931, 1597, 1490, 1442, 906; EI-MS (m/z, relative intensity) 282
(M+, 100), 267 (81), 252 (11), 239 (5), 207 (9), 189 (10), 178 (5),
165 (6), 138 (5), 125 (9); HRMS (ESI) calcd for C22H19 [(M+H)+]
283.1481, found: 283.1481.
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2-(3,3-Diphenylpropa-1,2-dien-1-yl)-6-methoxynaphthalene (3e).
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether : ethyl acetate = 30 : 1) to afford pure 3e as a
(3-(Cyclohex-1-en-1-yl)propa-1,2-diene-1,1-diyl)dibenzene (3j).
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether) to afford pure 3j as a yellow oil (34 mg, 63%);
1H NMR (400 MHz, CDCl3) δ 7.23-7.20 (m, 8H), 7.15-7.20 (m, 2
H), 6.29 (s, 1H), 5.70 (m, 1H), 2.05-2.06 (m, 4H), 1.52-1.59 (m,
4H); 13C NMR (100 MHz, CDCl3) δ 206.29, 136.95, 132.07,
128.35, 128.32, 127.29, 127.11, 112.37, 100.87, 26.04, 25.94,
22.48, 22.36; IR (film, cm-1) 1924, 1597, 1491, 1450, 1075, 1029;
EI-MS (m/z, relative intensity) 272 (M+, 100), 243 (12), 229 (13),
215 (14), 191 (17), 165 (20), 115 (17); HRMS (ESI) calcd for
C21H21 [(M+H)+] 273.1638, found: 273.1638.
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yellow solid (38 mg, 88%); H NMR (400 MHz, CDCl3) δ 7.64-
7.67 (m, 3H), 7.54-7.56 (m, 1H), 7.45-7.47 (m, 4H), 7.26-7.36
(m, 6H), 7.08-7.13 (m, 2H), 6.84 (s, 1H), 3.87 (s, 3H); 13C NMR
(100 MHz, CDCl3) δ 208.58, 157,69, 136.29, 134.01, 129.26,
129.17, 129.04, 128.48, 127.54, 127.33, 125.81, 125.24, 118.97,
113.80, 105.95, 98.07, 55.25 (one peak was missed because of
overlap); IR (film, cm-1) 1923, 1629, 1604, 1491, 1389, 1266,
1234, 1172, 1030; HRMS (ESI) calcd for C26H21O [(M+H)+]
349.1587, found: 349.1588.
(3-(4-Fluorophenyl)propa-1,2-diene-1,1-diyl)dibenzene
(3f).
Hepta-1,2-diene-1,1-diyldibenzene(3k). Following the typical
procedure above, the crude residue was purified by column
chromatography on silica gel (eluted with petroleum ether) to
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether) to afford pure 3f as a yellow oil (39 mg, 68%);
1H NMR (400 MHz, CDCl3) δ 7.39-7.42 (m, 4H), 7.27-7.37 (m,
8H), 6.98-7.00 (m, 2H), 6.67 (s, 1H); 13C NMR (100 MHz,
CDCl3) δ 207.94，162.17 (d, J = 245.0 Hz), 136.06, 129.83 (d, J
= 31.0 Hz), 128.51, 128.43, 128.36, 127.65, 115.76 (d, J = 17.0
Hz), 113.93, 96.73; IR (film, cm-1) 1930, 1600, 1506, 1490, 1225,
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afford pure 3k as a colorless oil (36 mg, 73%); H NMR (400
MHz, CDCl3) δ 7.22-7.29 (m, 8H), 7.13-7.19 (m, 2H), 5.61 (t, J
= 6.8 Hz, 1H), 2.08-2.14 (m, 2H), 1.39-1.46 (m, 2H), 1.24-1.33
(m, 2H), 0.81 (t, J = 7.2 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ
205.40, 137.31, 128.35, 128.27, 126.90, 109.61, 94.36, 31.37,
28.73, 22.30, 13.88; IR (film, cm-1) 1942, 1597, 1491, 1452,
1442, 1074, 1058; EI-MS (m/z, relative intensity) 248 (M+, 5),
219 (4), 206 (100), 191 (32), 178 (8), 165 (10), 128 (12), 115
(11), 91 (50); HRMS (ESI) calcd for C19H21 [(M+H)+] 249.1638,
found 249.1637.
51 1155; EI-MS (m/z, relative intensity) 286 (M+, 100), 270 (12),
209 (27), 190 (5), 183 (11), 134 (15); RMS (ESI) calcd for
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60
61
62
63
64
65
C21H16F [(M+H)+] 287.1230, found: 287.1230.
(3-(4-(Trifluoromethyl)phenyl)propa-1,2-diene-1,1-
3,3'-(3-Phenylpropa-1,2-diene-1,1-
diyl)dibenzene (3g). Following the typical procedure above, the
crude residue was purified by column chromatography on silica
gel (eluted with petroleum ether) to afford pure 3g as a yellow oil
(61 mg, 90%); 1H NMR (400 MHz, CDCl3) δ 7.56 (d, J = 8.4 Hz,
2H), 7.48 (d, J = 8.0 Hz, 2H), 7.40-7.42 (m, 4H), 7.29-7.38 (m,
6H), 6.72 (s, 1 H); 13C NMR (100 MHz, CDCl3) δ 209.03, 137.89,
diyl)bis((trifluoromethyl)benzene) (4a). Following the typical
procedure above, the crude residue was purified by column
chromatography on silica gel (eluted with petroleum ether) to
afford pure 4a as a yellow oil (71 mg, 88%); 1H NMR (400 MHz,
CDCl3) δ 7.55 (s, 2H), 7.48 (d, J = 7.2 Hz, 4H), 7.38 (t, J = 8.0

5
Hz, 2H), 7.30-7.33 (m, 2H), 7.24-7.28 (m, 2H), 7.13-7.20 (m,
1H), 6.73 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 206.64, 136.62,
132.67, 131.56, 131.25 (q, J = 37.2 Hz), 129.24, 129.03, 128.05,
127.18, 124.94 (q, J = 37.2 Hz), 124.68 (q, J = 3.8 Hz), 123.97 (q,
J = 270.9 Hz), 112.01, 99.11; IR (film, cm-1) 1939, 1599, 1489,
1443, 1330, 1250, 1166, 1124, 1093, 1073; EI-MS (m/z, relative
intensity) 404 (M+, 100), 385 (5), 335 (52), 320 (4), 265 (11),
189 (10), 157 (2), 131 (4); HRMS (ESI) calcd for C23H15F6
[(M+H)+] 405.1073, found: 405.1073.
petroleum ether) to afford pure 4f as a yellow oil (57 mg, 94%);
ACCEPTED MANUSCRIPT
1H NMR (400 MHz, CDCl3) δ 7.22-7.31 (m, 8H), 7.14-7.17 (m,
1H), 6.92-6.98 (m, 4H), 6.60 (s, 1H); 13C NMR (100 MHz,
CDCl3) δ 207.85, 162.37 (d, J = 245.6 Hz), 133.55, 132.00 (d, J
= 3.2 Hz), 129.94 (d, J = 8.0 Hz), 128.88, 127.59, 126.96, 115.51
(d, J = 21.4 Hz), 112.02, 97.99; IR (film, cm-1) 1930, 1600, 1504,
1224, 1156, 1067; EI-MS (m/z, relative intensity) 304 (M+, 100),
283 (11), 270 (5), 227 (7), 209 (15), 183 (9), 141 (7), 131 (5),
107 (4); HRMS (ESI) calcd for C21H15F2 [(M+H)+] 305.1136,
found: 305.1136.
1
2
3
4
5
6
7
8
9
4,4'-(3-Phenylpropa-1,2-diene-1,1-diyl)bis(methoxybenzene) (4b).
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether : ethyl acetate = 30 : 1) to afford pure 4b as a
yellow oil (61 mg, 93%); 1H NMR (400 MHz, CDCl3) δ 7.21-
7.32 (m, 8H), 7.10-7.15 (m, 1H), 6.78-6.81 (m, 4H), 6.57 (s, 1H),
3.72 (s, 6H); 13C NMR (100 MHz, CDCl3) δ 207.69, 159.61,
134.37, 129.54, 128.73, 128.59, 127.15, 126.87, 113.90, 112.82,
97.34, 55.28; IR (film, cm-1) 1924, 1605, 1508, 1462, 1247, 1172,
1032; EI-MS (m/z, relative intensity) 328 (M+, 100), 313 (15),
297 (12), 281 (87),253 (19), 207 (98), 191 (13), 164 (15), 147
(13), 126 (17); HRMS (ESI) calcd for C23H21O2 [(M+H)+]
329.1536, found: 329.1535.
1-Fluoro-4-(1-(4-methoxyphenyl)-3-phenylpropa-1,2-dien-1-
yl)benzene (4g). Following the typical procedure above, the crude
residue was purified by column chromatography on silica gel
(eluted with petroleum ether : ethyl acetate = 30 : 1) to afford
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
1
pure 4g as a yellow oil (36 mg, 57%); H NMR (400 MHz,
CDCl3) δ 7.29-7.39 (m, 8H), 7.20-7.24 (m, 1H), 7.00-7.04 (m, 2
H), 6.86-6.90 (m, 2H), 6.67 (s, 1H), 3.8 (s, 3H); 13C NMR (100
MHz, CDCl3) δ 207.75, 162.27 (d, J = 245.2 Hz), 159.26, 133.94,
132.38 (d, J = 3.2 Hz), 129.99 (d, J = 8.0 Hz), 129.47, 128.80,
128.13, 127.36, 115.35 (d, J = 21.4 Hz), 113.99, 112.42, 97.85,
55.28; IR (film, cm-1) 1930, 1604, 1506, 1248, 1175, 1034;
HRMS (ESI) calcd for C22H18FO [(M+H)+] 317.1336, found:
317.1336.
4,4'-(3-Phenylpropa-1,2-diene-1,1-diyl)bis(chlorobenzene) (4c).
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether) to afford pure 4c as a yellow oil (56 mg, 83%);
1H NMR (400 MHz, CDCl3) δ 7.32-7.39 (m, 13H), 6.72 (s, 1H);
13C NMR (100 MHz, CDCl3) δ 208.16, 134.28, 133.60, 133.18,
129.60, 128.92, 128.78, 127.74, 127.02, 112.04, 98.36; IR (film,
cm-1) 1928, 1589, 1488, 1395, 1090, 1014; EI-MS (m/z, relative
intensity) 336 (M+, 23), 301 (52), 281 (11), 265 (40), 224 (10),
207 (100), 191 (15), 178 (11), 147 (9), 133 (16), 91 (17); HRMS
(ESI) calcd for C21H15Cl2 [(M+H)+] 337.0545, found: 337.0547.
(1-(4-Methoxyphenyl)propa-1,2-diene-1,3-diyl)dibenzene (4h).
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether : ethyl acetate = 30 : 1) to afford pure 4h as a
1
yellow oil (52 mg, 88%); H NMR (400 MHz, CDCl3) δ 7.38-
7.44 (m, 4H), 7.25-7.36 (m, 7H), 7.18-7.22 (m, 1H), 6.86-6.89
(m, 2H), 6.67 (s, 1H), 3.78 (s, 3H); 13C NMR (100 MHz, CDCl3)
δ 207.97, 159.17, 136.42, 134.09, 129.57, 128.75, 128.43, 128.40,
128.27, 127.50, 127.25, 126.91, 113.91, 113.27, 97.52, 55.27; IR
(film, cm-1) 1927, 1064, 1508, 1248, 1174, 1035; EI-MS (m/z,
relative intensity) 298 (M+, 90), 283 (100), 252 (10), 220 (12),
207 (90), 191 (81), 178 (52), 165 (50), 132 (11), 115 (52), 105
(20); HRMS (ESI) calcd for C22H19O [(M+H)+] 299.1431, found:
299.1431.
4-(1,3-Diphenylpropa-1,2-dien-1-yl)-1,1'-biphenyl
(4d).
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether) to afford pure 4d as a yellow oil (60 mg, 87%);
1H NMR (400 MHz, CDCl3) δ 7.56-7.60 (m, 4H), 7.40-7.46 (m,
8H), 7.28-7.38 (m, 6H), 7.20-7.24 (m, 1H), 6.73 (s, 1H); 13C
NMR (100 MHz, CDCl3) δ 208.43, 140.67, 140.40, 136.09,
135.07, 133.80, 128.81, 128.79, 128.78, 128.52, 127.64, 127.41,
127.32, 127.20, 126.99, 113.45, 97.82 (two peaks ware missed
because of overlap); IR (film, cm-1) 1928, 1598, 1486, 1446,
1073, 1007; HRMS (ESI) calcd for C27H21 [(M+H)+] 345.1638,
found: 345.1629.
2-(4-Phenylbuta-2,3-dien-2-yl)naphthalene (4i). Following the
typical procedure above, the crude residue was purified by
column chromatography on silica gel (eluted with petroleum
1
ether) to afford pure 4i as a yellow oil (16 mg, 31%); H NMR
(400 MHz, CDCl3) δ 7.71-7.88 (m, 4H), 7.59-7.64 (m, 1H), 7.41-
7.50 (m, 4H), 7.29-7.38 (m, 2H), 7.19-7.23 (m, 1H), 6.55 (q, J =
2.8 Hz, 1H), 2.34 (d, J = 2.8 Hz, 3H); 13C NMR (100 MHz,
CDCl3) δ 207.55, 134.47, 133.75, 133.63, 132.56, 128.73, 128.03,
127.83, 127.57, 127.07, 126.95, 126.15, 125.78, 124.98, 123.65,
104.82, 96.83, 16.81; IR (film, cm-1) 1922, 1681, 1629, 1597,
1503, 1393, 1230, 1065; EI-MS (m/z, relative intensity) 256 (M+,
100), 241 (50), 216 (32), 207 (98), 191 (23), 178 (30), 165 (43),
141 (72), 128 (73), 115 (33), 91 (17); HRMS (ESI) calcd for
C20H17 [(M+H)+] 257.1325, found 257.1325.
4,4'-(3-Phenylpropa-1,2-diene-1,1-diyl)bis(methylbenzene) (4e).
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with
petroleum ether) to afford pure 4e as a yellow oil (57 mg, 94%);
1H NMR (400 MHz, CDCl3) δ 7.39-7.41 (m, 2H), 7.29-7.33 (m,
6H), 7.19-7.23 (m, 1H), 7.15 (d, J = 8.0 Hz, 4H), 6.67 (s, 1H),
2.36 (s, 6H); 13C NMR (100 MHz, CDCl3) δ 207.98, 137.32,
134.18, 133.28, 129.15, 128.73, 128.32, 127.19, 126.92, 113.39,
97.42, 21.17; IR (film, cm-1) 1926, 1599, 1509, 1406, 1259, 1066;
EI-MS (m/z, relative intensity) 296 (M+, 72), 281 (61), 253 (10),
236 (11), 222 (12), 207 (85), 191 (100), 178 (12), 165 (21), 126
(13), 115 (52); HRMS (ESI) calcd for C23H21 [(M+H)+] 297.1638,
found: 297.1635.
4,4'-(3-(4-Bromophenyl)propa-1,2-diene-1,1-
diyl)bis(chlorobenzene) (4j). Following the typical procedure
above, the crude residue was purified by column chromatography
on silica gel (eluted with petroleum ether) to afford pure 4j as a
1
yellow oil (68 mg, 82%); H NMR (400 MHz, CDCl3) δ 7.43-
7.45 (m, 2H), 7.21-7.33 (m, 8H), 7.21-7.24 (m, 2H), 6.66 (s, 1H);
13C NMR (100 MHz, CDCl3) δ 208.19, 133.91, 133.79, 132.19,
132.03, 129.58, 128.84, 128.46, 121.44, 122.49, 97.55; IR (film,
cm-1) 1928, 1950, 1486, 1400, 1090, 1012; HRMS (ESI) calcd
for C21H14BrCl2 [(M+H)+] 414.9650, found: 414.9645.
4,4'-(3-Phenylpropa-1,2-diene-1,1-diyl)bis(fluorobenzene) (4f).
Following the typical procedure above, the crude residue was
purified by column chromatography on silica gel (eluted with

6
Tetrahedron
ACCEPTED MANUSCRIPT
5384; (e) Neff, R.; Frantz, D. ACS. Catal. 2014, 4, 519.
4,4'-(3-(m-Tolyl)propa-1,2-diene-1,1-diyl)bis(chlorobenzene)
5. For selected recent examples, see: (a) Deutsch, C.; Lipshutz, B. H.;
Krause, N. Angew. Chem. Int. Ed. 2007, 46, 1650; (b) Pu, X.; Ready, J.
M. J. Am. Chem. Soc. 2008, 130, 10874; (c) Tang, M.; Fan, C. -A.;
Zhang, F. -M.; Tu, Y. -Q.; Zhang, W. -X.; Wang, A. -X. Org. Lett. 2008,
10, 5585; (d) Lo, V. K. -Y.; Wong, M. -K.; Che, C. -M. Org. Lett. 2008,
10, 517; (e) Liu, H.; Leow, D.; Huang, K. -W.; Tan, C. -H. J. Am. Chem.
Soc. 2009, 131, 1712; (f) Ogasawara, M.; Okada, A.; Nakajima, K.;
Takahashi, T. Org. Lett. 2009, 11, 177; (g) Kolakowski, R. V.; Manpadi,
M.; Zhang, Y.; Emge, T. J.; Williams, L. J. J. Am. Chem. Soc. 2009,
131, 12910; (h) Zhao, X.; Zhong, Z.; Peng, P.; Zhang, W.; Wang, J.
Chem. Commun. 2009, 2535; (i) Bolte, B.; Odabachian, Y.; Gagosz, F.
J. Am. Chem. Soc. 2010, 132, 7294; (j) Lo, V. K. -Y.; Zhou, C. -Y.;
Wong, M. -K.; Che, C. -M. Chem. Commun. 2010, 46, 213.
(4k). Following the typical procedure above, the crude residue
was purified by column chromatography on silica gel (eluted
with petroleum ether) to afford pure 4k as a yellow oil (63 mg,
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
1
90%); H NMR (400 MHz, CDCl3) δ 7.29-7.33 (m, 8H), 7.17-
7.22 (m, 3H), 7.06 (d, J = 7.2 Hz, 1H), 6.68 (s, 1H); 13C NMR
(100 MHz, CDCl3) δ 208.21, 138.60, 134.32, 133.54, 133.03,
129.59, 128.81, 128.75, 128.58, 127.65, 124.17, 111.87, 98.40,
21.39; IR (film, cm-1) 1929, 1604, 1488, 1397, 1090, 1013; EI-
MS (m/z, relative intensity) 350 (M+, 10), 315 (9), 225 (8), 207
(100), 191 (13), 132 (10), 95 (12), 73 (30); HRMS (ESI) calcd
for C22H17Cl2 [(M+H)+] 351.0702, found: 351.0699.
6. (a) Ahmed, M.; Arnuald, T.; Barrett, A. G. M.; Braddock, D. C.; Flack,
K.; Procopiou, P. A. Org. Lett. 2000, 2, 551; (b) Lavallo, V.; Frey, G.
D.; Kouser, S.; Donnadieu, B.; Bertrand, G. Proc. Natl. Acad. Sci. USA
2007, 104, 13569.
4,4'-(3-(2-Chlorophenyl)propa-1,2-diene-1,1-
diyl)bis(methoxybenzene) (4l). Following the typical procedure
above, the crude residue was purified by column chromatography
on silica gel (eluted with petroleum ether : ethyl acetate = 30 : 1)
to afford pure 4l as a yellow oil (52 mg, 74%);1H NMR (400
MHz, CDCl3) δ 7.54-7.56 (m, 1 H), 7.32-7.36 (m, 5H), 7.10-7.19
(m, 3H), 6.87-6.90 (m, 4 H), 3.81 (s, 6H); 13C NMR (100 MHz,
CDCl3) δ 208.61, 159.22, 132.24, 131.97, 129.89, 129.54, 128.20,
128.11, 126.73, 113.93, 113.02, 93.68, 55.28 (one peak was
missed because of overlap); IR (film, cm-1) 1928, 1606, 1509,
7. (a) Rona, P.; Crabbé, P. J. Am. Chem. Soc. 1969, 91, 3289; (b) Dollat, J.
M.; Luche, J. L.; Crabbé, P. J. Chem. Soc. Chem. Commun. 1977, 761;
(c) Crabbé, P.; Fillion, H.; André, D.; Luche, J. L.; J. Chem. Soc. Chem.
Commun. 1979, 860; (d) Crabbé, P.; André, D.; Fillion, H. Tetrahedron
Lett. 1979, 20, 893; (e) Searles, S.; Li, Y.; Nassim, B.; Lopes, M.-T. R.;
Tran, P. T.; Crabbé, P. J. Chem. Soc. Perkin Trans. 1 1984, 747.
8. (a) Kuang, J.; Ma, S. J. Org. Chem. 2009, 74, 1763; (b) Kuang, J.; Ma,
S. J. Am. Chem. Soc. 2010, 132, 1786; (c) Kuang, J.; Luo, H.; Ma, S.
Adv. Synth. Catal. 2012, 354, 933; (d) Ye, J.; Li, S.; Chen, B.; Fan, W.;
Kuang, J.; Liu, J.; Liu, Y.; Miao, B.; Wan, B.; Wang, Y.; Xie, X.; Yu,
Q.; Yuan, W.; Ma, S. Org. Lett. 2012, 14, 1346; (e) Chen, B.; Wang, N.;
Fan, W.; Ma, S. Org. Biomol. Chem. 2012, 10, 8465; (f) Ye, J.; Fan, W.;
Ma, S. Chem. Eur. J. 2013, 19, 716; (g) Kuang, J.; Xie, X.; Ma, S.
Synthesis 2013, 45, 592; (h) Tang, X.; Zhu, C.; Cao, T.; Kuang, J.; Lin,
W.; Ni, S.; Zhang, J.; Ma, S. Nat. Commun. 2013, 4, 2450.
20 1247, 1173, 1034; EI-MS (m/z, relative intensity) 362 (M+, 20),
342 (35), 332 (9), 281 (12), 267 (8), 207 (100), 191 (7), 165 (7),
147 (11), 96 (10), 73 (21); HRMS (ESI) calcd for C23H20ClO2
[(M+H)+] 363.1146, found 363.1148.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
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45
46
47
48
49
50
51
52
53
54
55
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58
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60
61
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64
65
9. (a) Xiao, Q.; Xia, Y.; Li, H.; Zhang, Y.; Wang, J. Angew. Chem. Int. Ed.
2011, 50, 1114; (b) Ye, F.; Hossain, M.; Xia, Y.; Ma, X.; Xiao, Q.;
Zhang, Y.; Wang, J. Chem. Asian J. 2013, 8, 1404; (c) Hossain, M.; Ye,
F.; Zhang, Y.; Wang, J. J. Org. Chem. 2013, 78, 1236; (d) Ye, F.; Wang,
C.; Ma, X.; Hossain, M. L.; Xia, Y.; Zhang, Y.; Wang, J. J. Org. Chem.
2015, 80, 647.
4,4'-(3-(m-Tolyl)propa-1,2-diene-1,1-diyl)bis(methoxybenzene)
(4m). Following the typical procedure above, the crude residue
was purified by column chromatography on silica gel (eluted
with petroleum ether : ethyl acetate = 30 : 1) to afford pure 4m as
1
a yellow oil (54 mg, 79%); H NMR (400 MHz, CDCl3) δ 7.33-
10. For related Cu-catalyzed allene formation from diazo compounds, see:
(a) Hassink, M.; Liu, X.; Fox, J. M. Org. Lett. 2011, 13, 2388. (b)
Mondal, S.; Nechab, M.; Campolo, D.; Vanthuyne, N.; Bertrand, M. P.
Adv. Synth. Catal. 2012, 354, 1987. (c) Poh, J.-S.; Tran, D. N.;
Battilocchio, C.; Hawkins, J. M.; Ley, S. V. Angew. Chem. Int. Ed.
2015, 54, 7920. (d) Tang, Y.; Chen, Q.; Liu, X.; Wang, G.; Lin, L.;
Feng, X. Angew. Chem. Int. Ed. 2015, 54, 9512.
11. For reviews, see: (a) Zhang, Y.; Wang, J. Eur. J. Org. Chem. 2011,
1015; (b) Xiao, Q.; Zhang, Y.; Wang, J. Acc. Chem. Res. 2013, 46, 236;
(c) Xia, Y.; Zhang, Y.; Wang, J. ACS Catal. 2013, 3, 2586.
7.36 (m, 4H), 7.20 (d, J = 3.6 Hz, 3H), 7.00-7.04 (m, 1H), 6.66-
6.89 (m, 4H), 3.80 (s, 6H), 2.32 (s, 3H); 13C NMR (100 MHz,
CDCl3) δ 207.69, 159.09, 138.34, 134.19, 129.52, 128.61, 128.00,
127.48, 124.03, 113.85, 112.63, 97.37, 55.27, 21.38; IR (film,
cm-1) 2928, 1605, 1508, 1247, 1173, 1033; EI-MS (m/z, relative
intensity) 342 (M+, 15), 253 (12), 207 (100), 165 (10), 135 (10),
96 (13), 73 (9); HRMS (ESI) calcd for C24H23O2 [(M+H)+]
343.1692, found 343.1692.
12. Hu, M.; Rong, J.; Miao, W.; Ni, C.; Han, Y.; Hu, J. J. Am. Chem. Soc.
2013, 135, 17302.
Acknowledgments
The project is supported by National Basic Research Program
(973 Program, No. 2012CB821600) and Natural Science
Foundation of China (Grant 21272010 and 21332002).
Supplementary data
Copies of 1H and/or 13C spectra for isolated products. This
material is available free of charge via the Internet at xxxxxxx.
References and notes
1. (a) Modern Allene Chemistry; Krause, N.; Hashmi, A. S. K., Eds.,
Wiley-VCH, Weinheim, Germany, 2004; Vols.1 and 2; (b) Ma, S.
Palladium-Catalyzed Two- or Three-Component Cyclization of
Functionalized Allenes in Palladium in Organic Synthesis; Tsuji, J., Ed.;
Springer, Berlin, 2005; pp183-210.
2. For recent reviews on allenes, see: (a) Tius, M. Acc. Chem. Res. 2003,
36, 284; (b) Ma, S. Acc. Chem. Res. 2003, 36, 701; (c) Wei, L.-L.;
Xiong, H.; Hsung, R. Acc. Chem. Res. 2003, 36, 773; (d) Brandsma, L.;
Nedolya, N. A. Synthesis 2004, 735; (e) Ma, S. Chem. Rev. 2005, 105,
2829; (f) Ma, S. Aldrichimica. Acta 2007, 40, 91; (g) Brasholz, M.;
Reissig, H. -U.; Zimmer, R. Acc. Chem. Res. 2009, 42, 45; (h) Ma, S.
Acc. Chem. Res. 2009, 42, 1679.
3. For reviews, see: (a) Hoffmann-Röder, A.; Krause, N. Angew. Chem. Int.
Ed. 2004, 43, 1196; (b) Kim, H.; Williams, L. Curr. Opin. Drug
Discovery Dev. 2008, 11, 891.
4. For recent reviews on the synthesis of allenes, see: (a) N. Krause, A.
Hoffmann-Röder, Tetrahedron 2004, 60, 11671; (b) K. M. Brummond,
J. E. Deforrest, Synthesis 2007, 795; (c) M. Ogasawara, Tetrahedron:
Asymmetry 2009, 20, 259; (d) Yu, S.; Ma, S. Chem. Commun. 2011, 47,